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SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectnet.rim.device.api.ui.Graphics
public class Graphics
Provides a surface on which applications can draw.
A graphics object encapsulates the state information needed for basic rendering operations, making it accessible to applications (for example, the current font, and drawing color).
Example
g = getGraphics(); // draw here pushContext(...); draw(g); popContext(); draw(Graphics g) { // draw or fill various objects // might {push, recurse paint(), pop} }
The context stack
Typically your application maintains one graphics object for each screen it
must present to the user. Each manager controlled by the screen uses that
graphics object to handle the layout and painting of each field the manager
contains.
To accomodate this model, the graphics object maintains an internal context stack. Each stack element contains the following information about the current drawing context:
Typically, a field's manager pushes a transform on the stack that describes the field's extent as the clipping region, and a drawing offset to position drawing. Then it hands the graphics object to the field when it requests the field to update itself.
Each transform pushed onto the stack describes the transform in terms of the parent coordinates, so that each draw operation can be done using local coordinates and translated back through the stack to finally appear on the appropriate location of the screen.
The drawing anchor
When you use one of this class's methods to draw an object, or text, you must
set the drawing anchor. This anchor describes the pixel in the
drawing region where the invoked method begins to draw. The coordinate system
for the drawing anchor assumes that the top left pixel in the region is
coordinate 0,0
.
The drawing anchor is not persistent. Each time you call one of these methods, you must provide a position for the anchor, and if maintaining information about relative positions of the anchor is important, then your code must do that.
What happens to clipped objects
When you draw an object and the size of that object would have a portion of
it fall outside the clipping region, then those portions are clipped off
(i.e. the object or text is cropped to fit the clipping region).
Drawing rectangles with rounded corners
You have a variety of methods for drawing rects with rounded corners. This
class identifies each logical corner with an associated static bitmask
constant with a name ending in _ROUNDED_RECT_CORNER, and this class also
provides pre-combined mask constants representing groups of corners (with
names ending in _ROUNDED_RECT_CORNERS). Combine these constants together to
pass to one of the appropriate draw methods
(such as Graphics.drawGradientFilledRoundedRect(net.rim.device.api.ui.XYRect, int, int, int, int)
), identifying which of
the rect's corners should render as rounded, and which should render as
squared off.
Drawing text
The Graphics class provides a variety of drawText
methods to
render text on the drawing surface. There are several versions of
drawText, taking single characters and various text classes. The most general
take a drawing anchor (x and y coordinates of the start of the text),
drawing position flags made up from bit flags specified as constants in
the DrawStyle
interface, and a width into which the text is drawn.
The drawing position flags specify both the baseline and the horizontal alignment. You combine them using the OR operator: e.g., BASELINE | HCENTER.
Baseline values:
The TOP baseline value draws the text below the drawing anchor.
The BOTTOM baseline value draws the text above the drawing anchor.
The BASELINE baseline value draws the text with its alphabetic baseline on the drawing anchor.
The VCENTER baseline value centers the text vertically on the drawing anchor.
Horizontal alignment values, used if a width greater than 0 is specified (a width of -1 forces left alignment; other values less than or equal to zero cause no text to be drawn):
The LEFT alignment value draws the text left-aligned to the paintable region. The paintable region is the area of the screen on which text can be drawn.
The HCENTER alignment value centers the text horizontally in the supplied width.
The RIGHT alignment value draws the text right-aligned to the paintable region. The paintable region is the area of the screen on which text can be drawn.
The HFULL (full justification) alignment value is not implemented by this interface, and is treated as identical to HCENTER.
By default, the drawText
methods assume the drawing position
flags (TOP | LEFT)
. You can request another method of drawing
the glyphs by passing other combinations of this class's constant drawing
position values.
Using DrawTextParam and TextMetrics
Some versions of drawText
allow more detailed control over the
way the text is drawn, and can return full text metrics. See the
DrawTextParam
and Graphics.WrappedTextMetrics
classes for details.
What happens to clipped text
The mechanism for handling clipping with drawText
operations is
slightly more complex.
The text drawing methods clip in two ways: pixels that fall outside the
general clipping region, and pixels that fall outside a text width
parameter specified to the appropriate drawText
method. Text
drawing methods that don't support a text width parameter use the width
of the whole text to be drawn.
If you pass the ELLIPSIS
constant to a drawText
method, in combination with the drawing position constants, then clipping by
the text width parameter is handled specially. The method replaces the last
fully rendered glyph, and any pixels of a partially rendered glyph, with the
ellipsis glyph (usually three dots, like this: ...).
If the ellipsis glyph itself would be clipped by the text width
parameter, then no ellipsis character is drawn.
You can use the TRUNCATE_BEGINNING
constant to truncate the
text at the start, not at the end, if it is wider than the supplied width. It
can be combined with ELLIPSIS
to put an ellipsis at the start
if truncation occurs.
Width of text rendered
All of the drawText
methods return the linear advance, in pixels, of
the text drawn. That is the amount by which the drawing position
is moved along the baseline by drawing the text. If you want to draw some more
text so that it joins with the text you have just drawn, the correct new
x anchor position is the old x anchor position plus this advance value
(assuming that you are drawing on a left-to-right baseline)
but see also AdvancedDrawTextParam.iAllowStartOverlap
.
You should also note that the advance width of drawn text returned by the
drawText
methods includes any pixels that are clipped
by the clipping region. However, if you pass a width parameter into the
drawText
method to constrain the region available for drawing,
and this width parameter clips the drawn text, the clipped pixels do
not count in the width of text rendered returned by the method.
You may further notice that since advance width can be less than the inked
pixels width (e.g. 'K' in BBAlphaSans or Georgia), if we pass width returned by
Font.measureText()
(x advance) into the drawText
method, the text drawn might get truncated. The drawText
tries to align
width of the inked pixels within the supplied width. For most of the cases, you may use
Font.getBounds()
which returns maximum of these widths.
Italics and kerning
Parts of italic characters often protrude beyond - before or after - the
horizontal bounds defined by the anchor position and the advance width. This
can also happen when two adjacent characters, like 'T' and 'o', are
automatically moved closer together, which is called kerning. If you need
to take account of kerning outside the advance width, you should either
use the ARTIC text layout system (see the ArticInterface
class),
or use Font.measureText
to obtain the full metrics.
Field Summary | ||
---|---|---|
static int |
ALL_ROUNDED_RECT_CORNERS
All four corners of a drawn rectangle should be rounded. |
|
static int |
BLACK
Black (0x00101010). |
|
static int |
BOTTOM_LEFT_ROUNDED_RECT_CORNER
Bottom-left corner of a drawn rectangle should be rounded. |
|
static int |
BOTTOM_RIGHT_ROUNDED_RECT_CORNER
Bottom-right corner of a drawn rectangle should be rounded. |
|
static int |
BOTTOM_ROUNDED_RECT_CORNERS
Both bottom corners of a drawn rectangle should be rounded. |
|
static byte |
CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
Cubic bezier control-point type for drawing paths. |
|
static byte |
CURVEDPATH_END_POINT
End-point type for drawing paths. |
|
static byte |
CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
Quadratic bezier control-point type for drawing paths. |
|
static int |
DRAWSTYLE_AALINES
Deprecated. use DRAWSTYLE_ANTIALIASED instead |
|
static int |
DRAWSTYLE_AAPOLYGONS
Deprecated. use DRAWSTYLE_ANTIALIASED instead |
|
static int |
DRAWSTYLE_ANTIALIASED
Drawing style for anti-aliased rendering of lines and polygons, used by Graphics.setDrawingStyle(int, boolean) and Graphics.isDrawingStyleSet(int) . |
|
static int |
DRAWSTYLE_FOCUS
This style is set by the framework when painting is being done for focus drawing. |
|
static int |
DRAWSTYLE_SELECT
This style is set by the framework when painting is being done for selection drawing. |
|
static int |
FULL_BLACK
Full black (0x00000000). |
|
static int |
FULL_WHITE
Full white (0x00ffffff). |
|
static int |
LEFT_ROUNDED_RECT_CORNERS
Both left-side corners of a drawn rectangle should be rounded. |
|
static int |
NO_ROUNDED_RECT_CORNERS
No corners of a drawn rectangle should be rounded. |
|
static int |
RIGHT_ROUNDED_RECT_CORNERS
Both right-side corners of a drawn rectangle should be rounded. |
|
static int |
ROP2_0
Binary raster op constant for zeroing out the destination. |
|
static int |
ROP2_1
Binary raster op constant for filling dest with 1 values. |
|
static int |
ROP2_D
Binary raster op constant for nop. |
|
static int |
ROP2_DSa
Binary raster op constant for masking ( source and dest ). |
|
static int |
ROP2_DSan
Binary raster op constant for ( not ( source and dest ) ). |
|
static int |
ROP2_DSna
Binary raster op constant for ( ( not source ) and dest ). |
|
static int |
ROP2_DSno
Binary raster op constant for ( ( not source ) or dest ). |
|
static int |
ROP2_DSo
Binary raster op constant for ( source or dest ). |
|
static int |
ROP2_DSon
Binary raster op constant for ( not ( source or dest ) ). |
|
static int |
ROP2_DSx
Binary raster op constant for selective invert ( source xor dest ). |
|
static int |
ROP2_DSxn
Binary raster op constant for ( not ( source xor dest ) ). |
|
static int |
ROP2_Dn
Binary raster op constant for invert destination. |
|
static int |
ROP2_S
Binary raster op constant for normal source copy. |
|
static int |
ROP2_SDna
Binary raster op constant for ( ( not dest ) and source ). |
|
static int |
ROP2_SDno
Binary raster op constant for ( source or ( not dest ) ). |
|
static int |
ROP2_Sn
Binary raster op constant for ( not source ). |
|
static int |
ROP_CONST_GLOBALALPHA
Deprecated. Use fillRect instead. |
|
static int |
ROP_SRCMONOEXPAND_ALPHA
Raster operation constant for expanding a monochrome source bitmap with current foreground and background drawing colors, respecting the alpha channel. |
|
static int |
ROP_SRCMONOEXPAND_COPY
Raster operation constant for expanding a monochrome source bitmap with the current foreground and background drawing colors. |
|
static int |
ROP_SRC_ALPHA
Raster operation constant for normal bitmap copy with an alpha channel. |
|
static int |
ROP_SRC_ALPHA_GLOBALALPHA
Raster operation constant for blending a source bitmap with an alpha channel and a constant global alpha value with destination pixels. |
|
static int |
ROP_SRC_COPY
Raster operation constant for normal bitmap copy. |
|
static int |
ROP_SRC_GLOBALALPHA
Raster operation constant for blending a source bitmap using a constant global alpha value with destination pixels. |
|
static boolean |
SCREEN_HAS_BORDER
Does the screen have a lit border around the drawable area of the screen? |
|
static int |
TOP_LEFT_ROUNDED_RECT_CORNER
Top-left corner of a drawn rectangle should be rounded. |
|
static int |
TOP_RIGHT_ROUNDED_RECT_CORNER
Top-right corner of a drawn rectangle should be rounded. |
|
static int |
TOP_ROUNDED_RECT_CORNERS
Both top corners of a drawn rectangle should be rounded. |
|
static int |
WHITE
White (0x00EBEBEB). |
Fields inherited from interface net.rim.device.api.ui.DrawStyle |
---|
BASELINE, BOTTOM, ELLIPSIS, HALIGN_MASK, HCENTER, HDEFAULT, HFULL, LEADING, LEFT, RIGHT, TOP, TRAILING, TRUNCATE_BEGINNING, VALIGN_MASK, VCENTER, VDEFAULT, VFULL |
Constructor Summary | ||
---|---|---|
Graphics(Bitmap bitmap)
Deprecated. Use the static factory method, Graphics.create(Bitmap) , instead. |
Method Summary | ||
---|---|---|
void |
clear()
Clears the entire graphics area to the current background color. |
|
void |
clear(int x,
int y,
int width,
int height)
Clears a region to the current background color. |
|
void |
clear(XYRect region)
Clears a region specified by an XYRect object to the current background color. |
|
boolean |
copyArea(int x,
int y,
int width,
int height,
int dx,
int dy)
Copies a region of this graphics canvas. |
|
boolean |
copyArea(XYRect region,
int dx,
int dy)
Copies a region of this graphics canvas, specified by an XYRect . |
|
static Graphics |
create(Bitmap bitmap)
Constructs a Graphics object for drawing to a bitmap. |
|
void |
drawARGB(int[] data,
int offset,
int scanLength,
int x,
int y,
int width,
int height)
Similar to drawRGB, but source data also contains alpha. |
|
void |
drawArc(int x,
int y,
int width,
int height,
int startAngle,
int arcAngle)
Draws an arc through a specified rectangle. |
|
void |
drawBitmap(int x,
int y,
int width,
int height,
Bitmap bitmap,
int left,
int top)
Draws a bitmap. |
|
void |
drawBitmap(XYRect dest,
Bitmap bitmap,
int left,
int top)
Draws a bitmap on a region specified by an XYRect object. |
|
void |
drawEllipse(int cx,
int cy,
int px,
int py,
int qx,
int qy,
int startAngle,
int arcAngle)
Draws an ellipse. |
|
void |
drawFilledPath(int[] xPts,
int[] yPts,
byte[] pointTypes,
int[] offsets)
Draws a set of filled paths. |
|
void |
drawGradientFilledRect(int x,
int y,
int width,
int height,
int startColor,
int endColor)
Draws an un-bordered rectangle with a gradient fill, from a provided point. |
|
void |
drawGradientFilledRect(int x,
int y,
int width,
int height,
int startColor,
int endColor,
boolean drawBorder)
Draws a rectangle with a gradient fill, from a provided point. |
|
void |
drawGradientFilledRect(XYRect rect,
int startColor,
int endColor)
Draws an un-bordered rectangle with a gradient fill. |
|
void |
drawGradientFilledRect(XYRect rect,
int startColor,
int endColor,
boolean drawBorder)
Draws a rectangle with a gradient fill. |
|
void |
drawGradientFilledRoundedRect(int x,
int y,
int width,
int height,
int startColor,
int endColor,
boolean drawBorder,
int arcWidth,
int arcHeight)
Draws a fully rounded rectangle with a gradient fill, from a provided point. |
|
void |
drawGradientFilledRoundedRect(int x,
int y,
int width,
int height,
int startColor,
int endColor,
boolean drawBorder,
int roundedCorners,
int arcWidth,
int arcHeight)
Draws a rounded rectangle with a gradient fill, from a provided point. |
|
void |
drawGradientFilledRoundedRect(int x,
int y,
int width,
int height,
int startColor,
int endColor,
int arcWidth,
int arcHeight)
Draws an un-bordered, fully rounded rectangle with a gradient fill, from a provided point. |
|
void |
drawGradientFilledRoundedRect(int x,
int y,
int width,
int height,
int startColor,
int endColor,
int roundedCorners,
int arcWidth,
int arcHeight)
Draws an un-bordered rectangle with a gradient fill, from a provided point. |
|
void |
drawGradientFilledRoundedRect(XYRect rect,
int startColor,
int endColor,
boolean drawBorder,
int arcWidth,
int arcHeight)
Draws a fully rounded rectangle with a gradient fill. |
|
void |
drawGradientFilledRoundedRect(XYRect rect,
int startColor,
int endColor,
boolean drawBorder,
int roundedCorners,
int arcWidth,
int arcHeight)
Draws a rounded rectangle with a gradient fill. |
|
void |
drawGradientFilledRoundedRect(XYRect rect,
int startColor,
int endColor,
int arcWidth,
int arcHeight)
Draws an un-bordered, fully rounded rectangle with a gradient fill. |
|
void |
drawGradientFilledRoundedRect(XYRect rect,
int startColor,
int endColor,
int roundedCorners,
int arcWidth,
int arcHeight)
Draws an un-bordered, rounded rectangle with a gradient fill. |
|
void |
drawImage(int x,
int y,
int width,
int height,
EncodedImage image,
int frameIndex,
int left,
int top)
Draws an encoded image. |
|
void |
drawImage(XYRect dest,
EncodedImage image,
int frameIndex,
int left,
int top)
Draws an encoded image on a region specified by an XYRect object. |
|
void |
drawLine(int x1,
int y1,
int x2,
int y2)
Draws a line. |
|
void |
drawOutlinedPath(int[] xPts,
int[] yPts,
byte[] pointTypes,
int[] offsets,
boolean closed)
Draw a set of path outlines. |
|
void |
drawPathOutline(int[] xPts,
int[] yPts,
byte[] pointTypes,
int[] offsets,
boolean closed)
Deprecated. Use Graphics.drawOutlinedPath(int[],int[],byte[],int[],boolean). |
|
void |
drawPoint(int x,
int y)
Draws a point. |
|
void |
drawRGB(int[] data,
int offset,
int scanLength,
int x,
int y,
int width,
int height)
Draws raw RGB data from an int array. |
|
void |
drawRect(int x,
int y,
int width,
int height)
Draws a rectangle. |
|
void |
drawRoundRect(int x,
int y,
int width,
int height,
int arcWidth,
int arcHeight)
Draws a rectangle with rounded edges. |
|
void |
drawRoundRect(int x,
int y,
int width,
int height,
int roundedCorners,
int arcWidth,
int arcHeight)
Draws an un-bordered rounded rectangle, from a provided point. |
|
void |
drawShadedFilledPath(int[] xPts,
int[] yPts,
byte[] pointTypes,
int[] colors,
int[] offsets)
Draws a set of shaded filled paths. |
|
int |
drawText(byte[] aText,
int aOffset,
int aLength,
int aX,
int aY,
int aFlags,
int aWidth)
Draws part of the contents of a byte array using the current font, clipping to the current clipping region, and using the baseline and alignment specified by aFlags and aWidth. |
|
int |
drawText(char aChar,
int aX,
int aY,
int aFlags,
int aWidth)
Draws a character using the current font and clipping to the current clipping region. |
|
int |
drawText(char[] aText,
int aOffset,
int aLength,
int aX,
int aY,
int aFlags,
int aWidth)
Draws part of the contents of a char array using the current font, clipping to the current clipping region, and using the baseline and alignment specified by aFlags and aWidth. |
|
int |
drawText(char[] aText,
int aOffset,
int aLength,
int aX,
int aY,
DrawTextParam aParam,
TextMetrics aMetrics)
Draws part of the text in a char array using the current font and clipping to the current clipping region. |
|
int |
drawText(String aText,
int aX,
int aY)
Draws the text in a string using the current font, clipping to the current clipping region and using the TOP baseline and LEFT alignment. |
|
int |
drawText(String aText,
int aX,
int aY,
int aFlags)
Draws the text in a string using the current font, clipping to the current clipping region and using the baseline specified by aFlags. |
|
int |
drawText(String aText,
int aX,
int aY,
int aFlags,
int aWidth)
Draws the text in a string using the current font, clipping to the current clipping region, and using the baseline and alignment specified by aFlags and aWidth. |
|
int |
drawText(String aText,
int aOffset,
int aLength,
int aX,
int aY,
int aFlags,
int aWidth)
Draws part of the text in a String using the current font, clipping to the current clipping region, and using the baseline and alignment specified by aFlags and aWidth. |
|
int |
drawText(String aText,
int aOffset,
int aLength,
int aX,
int aY,
DrawTextParam aParam,
TextMetrics aMetrics)
Draws part of the text in a String using the current font and clipping to the current clipping region. |
|
int |
drawText(StringBuffer aText,
int aOffset,
int aLength,
int aX,
int aY,
int aFlags,
int aWidth)
Draws part of the text in a StringBuffer using the current font, clipping to the current clipping region, and using the baseline and alignment specified by aFlags and aWidth. |
|
int |
drawText(StringBuffer aText,
int aOffset,
int aLength,
int aX,
int aY,
DrawTextParam aParam,
TextMetrics aMetrics)
Draws part of the text in a StringBuffer using the current font and clipping to the current clipping region. |
|
int |
drawTextOnPath(char[] aText,
int aOffset,
int aLength,
int aOriginX,
int aOriginY,
int[] aXPoints,
int[] aYPoints,
byte[] aPointTypes,
int[] aContourStarts,
DrawTextParam aParam,
TextMetrics aMetrics)
Draws text along a path. |
|
int |
drawTextOnPath(String aText,
int aOffset,
int aLength,
int aOriginX,
int aOriginY,
int[] aXPoints,
int[] aYPoints,
byte[] aPointTypes,
int[] aContourStarts,
DrawTextParam aParam,
TextMetrics aMetrics)
Draws text along a path. |
|
int |
drawTextOnPath(StringBuffer aText,
int aOffset,
int aLength,
int aOriginX,
int aOriginY,
int[] aXPoints,
int[] aYPoints,
byte[] aPointTypes,
int[] aContourStarts,
DrawTextParam aParam,
TextMetrics aMetrics)
Draws text along a path. |
|
void |
drawTexturedPath(int[] xPts,
int[] yPts,
byte[] pointTypes,
int[] offsets,
int xOrigin,
int yOrigin,
int dux,
int dvx,
int duy,
int dvy,
Bitmap textureData)
Draws a set of texture-filled paths. |
|
void |
fillArc(int x,
int y,
int width,
int height,
int startAngle,
int arcAngle)
Fills a circular or elliptical arc covering a specified rectangle. |
|
void |
fillEllipse(int cx,
int cy,
int px,
int py,
int qx,
int qy,
int startAngle,
int arcAngle)
Fills an ellipse. |
|
void |
fillRect(int x,
int y,
int width,
int height)
Fills a rectangle. |
|
void |
fillRoundRect(int x,
int y,
int width,
int height,
int arcWidth,
int arcHeight)
Fills a rectangle with rounded edges. |
|
void |
getAbsoluteClippingRect(XYRect clip)
Retreives the absolute coordinates of current clipping region. |
|
int |
getBackgroundColor()
Retrieves the current background color. |
|
XYRect |
getClippingRect()
Retrieves the local coordinates of current clipping region. |
|
int |
getColor()
Retrieves the current foreground drawing color. |
|
int |
getContextStackSize()
Retrieves the size of the stack of drawing contexts. |
|
void |
getDrawingOffset(XYPoint offset)
Retrieves the absolute coordinates for the current drawing offset. |
|
Font |
getFont()
Retrieves the current font for the current graphics context. |
|
int |
getGlobalAlpha()
Retrieves the current global alpha value. |
|
int |
getNearestColor(int color)
Gets the color that will be used if the specified color is requested. |
|
static int |
getNumColors()
Deprecated. Use Display.getNumColors(); |
|
static int |
getScreenHeight()
Deprecated. Use Display.getHeight() |
|
static int |
getScreenHorizontalResolution()
Deprecated. Use Display.getHorizontalResolution() |
|
static int |
getScreenVerticalResolution()
Deprecated. Use Display.getVerticalResolution() |
|
static int |
getScreenWidth()
Deprecated. Use Display.getWidth() |
|
int |
getStipple()
Retrieves the current line stippling value. |
|
int |
getTranslateX()
Retrieves the horizontal component of the current drawing offset. |
|
int |
getTranslateY()
Retrieves the vertical component of the current drawing offset. |
|
void |
invert(int x,
int y,
int width,
int height)
Inverts a region. |
|
void |
invert(XYRect rect)
Inverts a region specified by an XYRect object. |
|
static boolean |
isColor()
Deprecated. Use Display.isColor(). |
|
boolean |
isDrawingStyleSet(int drawStyle)
Determines whether the specified drawing style is turned on. |
|
boolean |
isRopSupported(int rop)
Determines if a raster operation is supported. |
|
void |
popContext()
Pops a drawing context off the stack. |
|
boolean |
pushContext(int x,
int y,
int width,
int height,
int xOffset,
int yOffset)
Pushes a clipping region (and optional drawing offset) onto the context stack. |
|
boolean |
pushContext(XYRect clip,
int xOffset,
int yOffset)
Pushes a clipping region (and optional drawing offset) onto the context stack. |
|
boolean |
pushRegion(int x,
int y,
int width,
int height,
int xScroll,
int yScroll)
Pushes a drawing region (and optional scroll offset) onto the context stack. |
|
boolean |
pushRegion(XYRect region)
Pushes a drawing region onto the context stack, specified by a XYRect object. |
|
boolean |
pushRegion(XYRect region,
int xScroll,
int yScroll)
Pushes a drawing region (and optional scroll offset) onto the context stack. |
|
void |
rop(int rop,
int x,
int y,
int width,
int height,
Bitmap source,
int left,
int top)
Executes an area raster operation on the specified region. |
|
void |
setBackgroundColor(int RGB)
Sets the current background color. |
|
void |
setColor(int RGB)
Sets the current color. |
|
void |
setDrawingStyle(int drawStyle,
boolean on)
Sets the current drawing style. |
|
void |
setFont(Font font)
Sets the current font for the current graphics context. |
|
void |
setGlobalAlpha(int alpha)
Sets the current global alpha value for drawing operations. |
|
void |
setStipple(int mask)
Sets the current line stippling value. |
|
void |
tileRop(int rop,
int x,
int y,
int width,
int height,
Bitmap source,
int left,
int top)
Executes an area raster operation on the specified region, tiling the source bitmap if necessary. |
|
void |
translate(int x,
int y)
Apply a translation to the current drawing offset. |
Methods inherited from class java.lang.Object |
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equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Field Detail |
---|
public static final int BLACK
public static final int WHITE
public static final int FULL_BLACK
public static final int FULL_WHITE
public static final int ROP_SRC_COPY
public static final int ROP_SRCMONOEXPAND_COPY
public static final int ROP_SRC_ALPHA
public static final int ROP_SRCMONOEXPAND_ALPHA
public static final int ROP_CONST_GLOBALALPHA
Set the global alpha value using Graphics.setGlobalAlpha(int)
.
public static final int ROP_SRC_GLOBALALPHA
Set the global alpha value using Graphics.setGlobalAlpha(int)
.
public static final int ROP_SRC_ALPHA_GLOBALALPHA
Set the global alpha value using Graphics.setGlobalAlpha(int)
.
public static final int ROP2_0
public static final int ROP2_DSon
public static final int ROP2_DSna
public static final int ROP2_Sn
public static final int ROP2_SDna
public static final int ROP2_Dn
public static final int ROP2_DSx
public static final int ROP2_DSan
public static final int ROP2_DSa
public static final int ROP2_DSxn
public static final int ROP2_D
public static final int ROP2_DSno
public static final int ROP2_S
public static final int ROP2_SDno
public static final int ROP2_DSo
public static final int ROP2_1
public static final int DRAWSTYLE_AALINES
Graphics.setDrawingStyle(int, boolean)
and Graphics.isDrawingStyleSet(int)
.
If this style is set, lines and path outlines may be antialiased.
This style is off by default.
public static final int DRAWSTYLE_AAPOLYGONS
Graphics.setDrawingStyle(int, boolean)
and Graphics.isDrawingStyleSet(int)
.
If this style is set, filled paths and polygons may be antialiased.
This style is off by default.
public static final int DRAWSTYLE_ANTIALIASED
Graphics.setDrawingStyle(int, boolean)
and Graphics.isDrawingStyleSet(int)
.
If this style is set, lines, path outlines, afilled paths and polygons may be antialiased.
This style is off by default.
public static final int DRAWSTYLE_FOCUS
public static final int DRAWSTYLE_SELECT
public static final byte CURVEDPATH_END_POINT
A curve or line ends on this point. The value of this constant will always be 0, so it is possible to just create a points array and set only the values of the curves' control points.
public static final byte CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
The control point of a quadratic bezier is the single point that "stretches" the curve awway from the end points. If a point is a quadratic bezier control point, the points preceeding and succeeding it must be end points.
public static final byte CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
A control point of a cubic bezier is one of two points that "stretch" the curve awway from the end points. Cubic bezier control points must come in sets of two, with end points coming before the first control point and after the second.
public static final int NO_ROUNDED_RECT_CORNERS
public static final int TOP_LEFT_ROUNDED_RECT_CORNER
public static final int TOP_RIGHT_ROUNDED_RECT_CORNER
public static final int BOTTOM_LEFT_ROUNDED_RECT_CORNER
public static final int BOTTOM_RIGHT_ROUNDED_RECT_CORNER
public static final int TOP_ROUNDED_RECT_CORNERS
public static final int BOTTOM_ROUNDED_RECT_CORNERS
public static final int LEFT_ROUNDED_RECT_CORNERS
public static final int RIGHT_ROUNDED_RECT_CORNERS
public static final int ALL_ROUNDED_RECT_CORNERS
public static final boolean SCREEN_HAS_BORDER
Constructor Detail |
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public Graphics(Bitmap bitmap)
Graphics.create(Bitmap)
, instead.
bitmap
- Writeable bitmap to draw into; must not be null.
IllegalArgumentException
- If your provided bitmap is not writeable
or too large to fit into the drawing cache.Method Detail |
---|
public static Graphics create(Bitmap bitmap)
bitmap
- Writeable bitmap to draw into. Must not be null and must be
the default bitmap type for the device.
IllegalArgumentException
- If your provided bitmap is not writeable
or too large to fit into the drawing chache.public void clear()
public void clear(int x, int y, int width, int height)
Use this method to clear only a region within the entire graphics area. You specify the region to clear by describing its extent in passed parameters.
x
- Left edge of the region.y
- Top edge of the region.width
- Width of the region.height
- Height of the region.public void clear(XYRect region)
Use this method to clear only a region within the entire graphics area. You specify the region to clear with an XYRect that you pass to this method.
region
- Rectangular region to clear.public boolean copyArea(int x, int y, int width, int height, int dx, int dy)
Use this method to copy a region of the drawing buffer. You specify the source region by describing its extent in passed parameters. The source region is left intact (i.e. not cleared).
To paste the copy of the region to the left of or above the drawing
anchor, specify a negative value for the dx
or
dy
parameters.
If a portion of the source rectangle lies outside the bounds of the
clipping region, this method does not copy the associated pixels. You can
refresh the omitted area by invoking paint
on the
component.
This method fails in situations where the pixels are not
available. This can happen when a front buffer screen is obscuring this
graphics context's screen. In this case, this method returns false; you
should then prompt a full repaint by invoking
invalidate
on the screen.
x
- Left edge of the source region.y
- Top edge of the source regionwidth
- Width of the source region.height
- Height of the source region.dx
- Horizontal distance to move the region.dy
- Vertical distance to move the region.
public boolean copyArea(XYRect region, int dx, int dy)
XYRect
.
Use this method to copy a region of the drawing buffer. You specify
the source region with an XYRect
that you pass to this
method. The source region is left intact (i.e. not cleared).
To paste the copy of the region to the left of or above the drawing
anchor, specify a negative value for the dx
and
dy
parameters.
If a portion of the source region lies outside the bounds of the
clipping region, this method does not copy the associated pixels. You can
refresh the omitted area by invoking Field.paint(net.rim.device.api.ui.Graphics)
on the component.
This method fails in situations where the pixels are not
available. This can happen when a front buffer screen is obscuring this
graphics context's screen. In this case, this method returns false; you
should then prompt a full repaint by invoking
invalidate
on the screen.
region
- Source region to copy.dx
- Horizontal distance to move the region.dy
- Vertical distance to move the region.
public void drawARGB(int[] data, int offset, int scanLength, int x, int y, int width, int height)
data
- offset
- scanLength
- x
- y
- width
- height
- public void drawArc(int x, int y, int width, int height, int startAngle, int arcAngle)
The center of the drawn arc is the center of a rectangle whose origin
is (x,y)
and whose size is specified by the
width
and height
parameters.
The arc begins at startAngle
and extends for
arcAngle
degrees, using the current draw color. The drawing
algorithm assumes that the 0 degree position is in the center of the
right edge of the rectangle. The direction of the arc drawn depends on
the relative values of startAngle
and arcAngle
:
(startAngle < arcAngle)
, this method draws the arc
in a counterclockwise direction.
startAngle > arcAngle
, this method draws the arc
in a clockwise direction.
The resulting arc covers an area width
pixels wide by
height
pixels tall and end points are one pixel outside the
extent of the rectangle). If either width or height is less than zero,
this method draws nothing.
The angles are specified relative to the non-square extents of the bounding rectangle such that 45 degrees always falls on the line from the center of the ellipse to the upper right corner of the bounding rectangle. As a result, if the bounding rectangle is noticeably longer in one axis than the other, the angles to the start and end of the arc segment will be skewed farther along the longer axis of the bounds. ATTENTION: This method doesn't support transformations specified in the setTransformation method.
x
- Horizontal coordinate of the arc's starting position.y
- Vertical coordinate of the arc's starting position.width
- Width of rectangle containing the arc.height
- Height of rectangle containing the arc.startAngle
- The angle position at which to commence drawing.arcAngle
- Angular extent of the arc, relative to the
start angle.public void drawEllipse(int cx, int cy, int px, int py, int qx, int qy, int startAngle, int arcAngle)
Draws an ellipse with the specified endpoints P = (px, py) and Q = (qx, qy) of two conjugate diameters of the ellipse. The endpoints are specified as absolute coordinates.
This example shows an ellipse with the aligned p and q points.
This example shows how the p and q points can be used to draw a non-aligned ellipse.
cx
- X-ordinate of the ellipse centre. cx is one of the coordinates of the center point of the ellipse.cy
- Y-ordinate of the ellipse centre.px
- X-ordinate of the point P. P is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the p point defines the x-axis radius.py
- Y-ordinate of the point P. P is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the p point defines the x-axis radius.qx
- X-ordinate of the point Q. Q is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the q point defines the y-axis radius.qy
- Y-ordinate of the point Q. Q is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the q point defines the y-axis radius.startAngle
- Arc start angle. Drawing starts at the angular position defined by the start angle
(clockwise with zero degrees being the x-axis and x left, y down) and ends at an angular position
equal to the start angle plus the arc angle. For example, if you set the start angle to 90 degrees
and the arc angle to 90 degrees, the ¼ ellipse starts at the y axis and continues to the x axis.arcAngle
- Angular extent of the arc, relative to the start angle.public boolean isRopSupported(int rop)
Use this method to query if a particular raster operation is
supported for the Graphics object. Note that all ROP2s as well as
Graphics.ROP_SRC_COPY
, Graphics.ROP_SRCMONOEXPAND_COPY
,
Graphics.ROP_SRC_ALPHA
and Graphics.ROP_SRCMONOEXPAND_ALPHA
are always
supported.
rop
- Constant for the raster operation to query.
public void rop(int rop, int x, int y, int width, int height, Bitmap source, int left, int top)
Use this method to run a raster operation with or without a source bitmap.
You must specify the extent of the region to draw to, as well as the top left position in the (optional) source bitmap.
rop
- Constant for the raster operation to execute.x
- Left edge of the destination region.y
- Top edge of the destination region.width
- Width of the destination region.height
- Height of the destination region.source
- Source bitmap to use (may be null for some raster operations)left
- Left edge of region within bitmap to use.top
- Top edge of region within bitmap to use.public void tileRop(int rop, int x, int y, int width, int height, Bitmap source, int left, int top)
Use this method to run a raster operation with or without a source bitmap.
You must specify the extent of the region to draw to, as well as the top left position in the (optional) source bitmap.
rop
- Constant for the raster operation to execute.x
- Left edge of the destination region.y
- Top edge of the destination region.width
- Width of the destination region.height
- Height of the destination region.source
- Source bitmap to use (may be null for some raster operations)left
- Left edge of region within bitmap to use.top
- Top edge of region within bitmap to use.public void drawBitmap(XYRect dest, Bitmap bitmap, int left, int top)
XYRect
object.
Use this method to draw a bitmap. You specify the destination region for the bitmap with an XYRect that you pass to this method.
You must also specify the extent of the bitmap to draw (the top left
corner of this extent defined by the top
and
left
parameters). If a portion of part of the bitmap you
want to draw falls outside the size of the destination region, this
method crops to fit.
dest
- Destination region in which to draw the bitmap.bitmap
- Bitmap to draw.left
- Left edge of region within bitmap to draw.top
- Top edge of region within bitmap to draw.public void drawBitmap(int x, int y, int width, int height, Bitmap bitmap, int left, int top)
Use this method to draw a bitmap. You specify the destination region for the bitmap by describing the extent of the region with passed parameters.
You must also specify the extent of the bitmap to draw (the top left
corner of this extent defined by the top
and
left
parameters). If a portion of part of the bitmap you
want to draw falls outside the size of the destination region, this
method crops to fit.
Pixels are drawn exactly as in the Bitmap, with no color transformations.
To have a monochrome image act like a rubber stamp, use Graphics.rop(int, int, int, int, int, net.rim.device.api.system.Bitmap, int, int)
with
Graphics.ROP_SRCMONOEXPAND_COPY
or Graphics.ROP_SRCMONOEXPAND_ALPHA
.
x
- Left edge of the destination region.y
- Top edge of the destination region.width
- Width of the destination region.height
- Height of the destination region.bitmap
- Bitmap to draw.left
- Left edge of region within bitmap to draw.top
- Top edge of region within bitmap to draw.public void drawImage(XYRect dest, EncodedImage image, int frameIndex, int left, int top)
XYRect
object.
Use this method to draw an image. You specify the destination region for the image with an XYRect that you pass to this method.
The region to be drawn is decoded, drawn and then thrown away. Thus
if you plan to draw a full encoded image multiple times it is faster to
first decode into a Bitmap
object and draw that.
You must also specify the extent of the image to draw (the top left
corner of this extent defined by the top
and
left
parameters). If a portion of part of the image you want
to draw falls outside the size of the destination region, this method
crops to fit.
dest
- Destination region in which to draw the bitmap.image
- Encoded image to drawframeIndex
- The frame to drawleft
- Left edge of region within bitmap to draw.top
- Top edge of region within bitmap to draw.public void drawImage(int x, int y, int width, int height, EncodedImage image, int frameIndex, int left, int top)
Use this method to draw an encoded image. You specify the destination region for the bitmap by describing the extent of the region with passed parameters.
The region to be drawn is decoded, drawn and then thrown away. Thus
if you plan to draw a full encoded image multiple times it is faster to
first decode into a Bitmap
object and draw that.
You must also specify the extent of the image to draw (the top left
corner of this extent defined by the top
and
left
parameters). If a portion of part of the image you want
to draw falls outside the size of the destination region, this method
crops to fit.
Pixels are drawn exactly as in the Bitmap, with no color transformations.
To have a monochrome image act like a rubber stamp, use Graphics.rop(int, int, int, int, int, net.rim.device.api.system.Bitmap, int, int)
with
Graphics.ROP_SRCMONOEXPAND_COPY
or Graphics.ROP_SRCMONOEXPAND_ALPHA
.
x
- Left edge of the destination region.y
- Top edge of the destination region.width
- Width of the destination region.height
- Height of the destination region.image
- Encoded image to draw.frameIndex
- The frame to drawleft
- Left edge of region within bitmap to draw.top
- Top edge of region within bitmap to draw.public void drawFilledPath(int[] xPts, int[] yPts, byte[] pointTypes, int[] offsets)
Use this method to draw one or more filled non-intersecting paths that contain line segments or curves. You specify the x and y coordinates and point types of the paths desired.
The offsets indicate the beginnings of each path in the data array. The data in the ith path is defined to be the (xPts,yPts) values from offsets[i] to offsets[i+1]-1 inclusive. Thus if there are N values in offsets, there are N-1 paths defined, where the final value is one greater than the offset where the final point of the final path is located in the points data. If offsets is null, the xPts and yPts data will be treated as a single path, and these arrays must have the same length.
The xPts and yPts arrays keep track of each vertex in the polygon and each value in the xPts array must have a corresponding value at the same index in the yPts array, and a corresponding value at the same index in the pointTypes array.
None of the edges in a path may cross any other edge in any of the paths (including itself). If edges do cross, the drawing behaviour is undefined. A path may be fully contained within another path, e.g. a "donut" shape.
The paths are filled by the "even-odd" rule. Thus if a ray is drawn from any point, the area containing the point will be filled if the ray passes through an odd number of edges and will not be filled if is passes through an even number of edges.
Note that each non-null array parameter must be a different array.
xPts
- Ordered list of x values for each vertex in the paths.yPts
- Ordered list of y values for each vertex in the paths.pointTypes
- One of Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
or Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
. There must be one of
these values for each (x,y) point defined. If pointTypes is null, all
point are assumed to be of type Graphics.CURVEDPATH_END_POINT
.
If a point's value is Graphics.CURVEDPATH_END_POINT
, then a line or
curve ends on this point. If a curve control point is next to this
point, a curve will have this point as an endpoint. Otherwise, straight
lines are drawn between successive end points.
If a point's value is Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
the point is a control point for a quadratic bezier. The control point of
a quadratic bezier is the single point that "stretches" the curve away
from the end points. If a point is a quadratic bezier control point, the
points preceeding and succeeding it must be end points
(Graphics.CURVEDPATH_END_POINT
).
If a point's value is Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
,
the point is a control point for a cubic bezier. A cubic bezier has two
control points that "stretch" the curve away from the end points. Cubic
bezier control points must come in sets of two, with end points
(Graphics.CURVEDPATH_END_POINT
) coming before the first control point and
after the second.
offsets
- List defining the beginnings of each path in the xPts/yPts
data arrays, or null to indicate a single path. A path that begins at
point (xPts[offsets[i]],yPts[offsets[i]]) will end at point
(xPts[offsets[i+1]]-1,yPts[offsets[i+1]]-1).
IllegalArgumentException
- If the data is malformed. For example,
the values in offsets is negative or not in increasing order, there are
fewer than 2 points in a single path, the values in offsets index outside
the points arrays, the values in pointTypes are invalid, or offsets is
null and xPts and yPts are not the same length.public void drawShadedFilledPath(int[] xPts, int[] yPts, byte[] pointTypes, int[] colors, int[] offsets)
Use this method to draw one or more filled non-intersecting paths that contain line segments and curves. You specify the x and y coordinates and point types of the paths desired as well as the color values of each vertex which will be blended together creating the shading effect.
The offsets indicate the beginnings of each path in the data array. The data in the ith path is defined to be the (xPts,yPts) values from offsets[i] to offsets[i+1]-1 inclusive. Thus if there are N values in offsets, there are N-1 paths defined, where the final value is one greater than the offset where the final point of the final path is located in the points data. If offsets is null, the xPts and yPts data will be treated as a single path, and these arrays must have the same length.
The xPts and yPts arrays keep track of each vertex in the polygon and each value in the xPts array must have a corresponding value at the same index in the yPts array, and a corresponding value at the same index in the pointTypes array. Similarly the color array stores the RGB color of each vertex ( in 0x00RRGGBB format ) and its indices must correspond with those of both the xPts and yPts arrays.
None of the edges in a path may cross any other edge in any of the paths (including itself). If edges do cross, the drawing behaviour is undefined. A path may be fully contained within another path, for example, a "donut" shape.
The paths are filled by the "even-odd" rule. Thus if a ray is drawn from any point, the area containing the point will be filled if the ray passes through an odd number of edges and will not be filled if is passes through an even number of edges.
Note that each non-null array parameter must be a different array.
xPts
- Ordered list of x values for each vertex in the paths.yPts
- Ordered list of y values for each vertex in the paths.pointTypes
- One of Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
or Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
. There must be one of
these values for each (x,y) point defined. If pointTypes is null, all
point are assumed to be of type Graphics.CURVEDPATH_END_POINT
.
If a point's value is Graphics.CURVEDPATH_END_POINT
, then a line or
curve ends on this point. If a curve control point is next to this
point, a curve will have this point as an endpoint. Otherwise, straight
lines are drawn between successive end points.
If a point's value is
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
, the point is a
control point for a quadratic bezier. The control point of a quadratic
bezier is the single point that "stretches" the curve awway from the end
points. If a point is a quadratic bezier control point, the points
preceeding and succeeding it must be end points (Graphics.CURVEDPATH_END_POINT
).
If a point's value is Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
,
the point is a control point for a cubic bezier. A cubic bezier has two
control points that "stretch" the curve away from the end points. Cubic
bezier control points must come in sets of two, with end points
(Graphics.CURVEDPATH_END_POINT
) coming before the first control point and after
the second.
colors
- Ordered list of color values for each vertex ( 0x00RRGGBB
format ). If null, a solid filled path will be drawn in the current
foreground color.offsets
- List defining the beginnings of each path in the xPts/yPts
data arrays, or null to indicate a single path. A path that begins at
point (xPts[offsets[i]],yPts[offsets[i]]) will end at point
(xPts[offsets[i+1]]-1,yPts[offsets[i+1]]-1).
IllegalArgumentException
- If the data is malformed. For example,
the values in offsets is negative or not in increasing order, there are
fewer than 2 points in a single path, the values in offsets index outside
the points arrays, the values in pointTypes are invalid, or offsets is
null and xPts and yPts are not the same length.public void drawPathOutline(int[] xPts, int[] yPts, byte[] pointTypes, int[] offsets, boolean closed)
Use this method to draw a set of path outlines that contains line segments and curves. The xPts and yPts arrays keep track of each vertex in the path. Each value in the xPts array must have corresponding values at the same index in the yPts array and the pointTypes array.
The offsets array keeps track of the locations of each path in the set of paths. If offsets is null, the xPts and yPts data will be treated as a single path, and these arrays must have the same length.
Note that each non-null array parameter must be a different array.
xPts
- Ordered list of x values for each vertex in the paths.yPts
- Ordered list of y values for each vertex in the paths.pointTypes
- One of Graphics.Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
or Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
. There must be one of
these values for each (x,y) point defined. If pointTypes is null, all
point are assumed to be of type Graphics.CURVEDPATH_END_POINT
.
If a point's value is Graphics.CURVEDPATH_END_POINT
, then a line or
curve ends on this point. If a curve control point is next to this
point, a curve will have this point as an endpoint. Otherwise, straight
lines are drawn between successive end points.
If a point's value is Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
the point is a control point for a quadratic bezier. The control point of a
quadratic bezier is the single point that "stretches" the curve awway
from the end points. If a point is a quadratic bezier control point, the
points preceeding and succeeding it must be end points
(Graphics.CURVEDPATH_END_POINT
).
If a point's value is Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
,
the point is a control point for a cubic bezier. A cubic bezier has two
control points that "stretch" the curve away from the end points. Cubic
bezier control points must come in sets of two, with end points
(Graphics.CURVEDPATH_END_POINT
) coming before the first control point and after
the second.
offsets
- List defining the beginnings of each path in the xPts/yPts
data arrays, or null to indicate a single path. A path that begins at
point (xPts[offsets[i]],yPts[offsets[i]]) will end at point
(xPts[offsets[i+1]]-1,yPts[offsets[i+1]]-1).closed
- If this value is true, each path in the set will be closed
by connecting the final point in the path's data with the first point.
IllegalArgumentException
- If the data is malformed. e.g. the
values in offsets is negative or not in increasing order, there are fewer
than 2 points in a single path, the values in offsets index outside the
points arrays, the values in pointTypes are invalid, or offsets is null
and xPts and yPts are not the same length.public void drawOutlinedPath(int[] xPts, int[] yPts, byte[] pointTypes, int[] offsets, boolean closed)
Use this method to draw a set of path outlines that contains line segments and curves. The xPts and yPts arrays keep track of each vertex in the path. Each value in the xPts array must have corresponding values at the same index in the yPts array and the pointTypes array.
The offsets array keeps track of the locations of each path in the set of paths. If offsets is null, the xPts and yPts data will be treated as a single path, and these arrays must have the same length.
Note that each non-null array parameter must be a different array.
xPts
- Ordered list of x values for each vertex in the paths.yPts
- Ordered list of y values for each vertex in the paths.pointTypes
- One of Graphics.Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
or Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
. There must be one of
these values for each (x,y) point defined. If pointTypes is null, all
point are assumed to be of type Graphics.CURVEDPATH_END_POINT
.
If a point's value is Graphics.CURVEDPATH_END_POINT
, then a line or
curve ends on this point. If a curve control point is next to this
point, a curve will have this point as an endpoint. Otherwise, straight
lines are drawn between successive end points.
If a point's value is Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
the point is a control point for a quadratic bezier. The control point of a
quadratic bezier is the single point that "stretches" the curve awway
from the end points. If a point is a quadratic bezier control point, the
points preceeding and succeeding it must be end points
(Graphics.CURVEDPATH_END_POINT
).
If a point's value is Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
,
the point is a control point for a cubic bezier. A cubic bezier has two
control points that "stretch" the curve away from the end points. Cubic
bezier control points must come in sets of two, with end points
(Graphics.CURVEDPATH_END_POINT
) coming before the first control point and after
the second.
offsets
- List defining the beginnings of each path in the xPts/yPts
data arrays, or null to indicate a single path. A path that begins at
point (xPts[offsets[i]],yPts[offsets[i]]) will end at point
(xPts[offsets[i+1]]-1,yPts[offsets[i+1]]-1).closed
- If this value is true, each path in the set will be closed
by connecting the final point in the path's data with the first point.
IllegalArgumentException
- If the data is malformed. e.g. the
values in offsets is negative or not in increasing order, there are fewer
than 2 points in a single path, the values in offsets index outside the
points arrays, the values in pointTypes are invalid, or offsets is null
and xPts and yPts are not the same length.public void drawTexturedPath(int[] xPts, int[] yPts, byte[] pointTypes, int[] offsets, int xOrigin, int yOrigin, int dux, int dvx, int duy, int dvy, Bitmap textureData)
Use this method to draw one or more texture-filled non-intersecting paths that contain line segments or curves. You specify the x and y coordinates and point types of the paths desired.
Specifying the positions of the vertices. The xPts and yPts arrays keep track of each vertex in the polygon and each value in the xPts array must have a corresponding value at the same index in the yPts array.
Specifying the type of each vertex. The pointTypes array
encodes the type of each point along the textured path: for example, the
third element in the pointTypes array describes the function of the
vertex at the position described by the third element in each of the xPts
and yPts arrays. The values in the pointTypes array match static
constants in this class, and should be equal to Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
or Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
.
If a point's value is Graphics.CURVEDPATH_END_POINT
, then a line or
curve ends on this point. If a curve control point is next to this point,
a curve will have this point as an endpoint. Otherwise, straight lines
are drawn between successive end points. This is the default value for
points (and if the pointTypes array is null, all points are assumed to be
end points).
If a point's value is Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
,
the point is a control point for a quadratic bezier. The control point
of a quadratic bezier is the single point that "stretches" the curve away
from the end points. If a point is a quadratic bezier control point, the
points preceeding and succeeding it must be end points.
If a point's value is Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
,
the point is a control point for a cubic bezier. A cubic bezier has two
control points that "stretch" the curve away from the end points. Cubic
bezier control points must come in sets of two, with end points coming
before the first control point and after the second.
Specifying the paths between vertices. The array of offset values indicates the beginnings of each path in the data array. The data in the ith path is defined to be the (xPts,yPts) values from offsets[i] to offsets[i+1]-1 inclusive. Thus if there are N values in offsets, there are N-1 paths defined, where the final value is one greater than the offset where the final point of the final path is located in the points data. If offsets is null, the xPts and yPts data will be treated as a single path, and these arrays must have the same length.
None of the edges in a path may cross any other edge in any of the paths (including itself). If edges do cross, the drawing behaviour is undefined. A path may be fully contained within another path, e.g. a "donut" shape.
The paths are filled by the "even-odd" rule. Thus if a ray is drawn from any point, the area containing the point will be filled if the ray passes through an odd number of edges and will not be filled if is passes through an even number of edges.
Specifying the texture to draw with. You provide a bitmap to
indicate the texture to draw with, in the textureData parameter.
Starting from the texture origin (as specified in local coordinates by
xOrigin
and yOrigin
), this method maps the
texture into the path, tiling as necessary to fill the region.
You use two walk vectors (dux
, dvx
) and
(duy
, dvy
) to describe the scale and angle the
method should use to map the texture: u and v are taken to correspond to
x and y, but in texture-space rather than in
screen-space. dux
and dvx
indicate how many u
and v coordinates to skip in the texture per x coordinate on the
screen. Likewise, duy
and dvy
indicate how many
texture coordinates to skip per y coordinate on the screen. These four
values are represented in 15.16 fixed point, allowing for eight bits of
decimal precision. Using these walk vectors it is possible to achieve
arbitrary rotation, scaling, and skewing on a given texture.
Note: Each non-null array parameter must be a different array.
xPts
- Ordered list of x values for each vertex in the paths.yPts
- Ordered list of y values for each vertex in the paths.pointTypes
- Ordered list of point types corresponding to the list.offsets
- List defining the beginnings of each path in the
xPts/yPts data arrays, or null to indicate a single path. A path that
begins at point (xPts[offsets[i]],yPts[offsets[i]]) will end at point
(xPts[offsets[i+1]]-1,yPts[offsets[i+1]]-1).xOrigin
- X component of the texture origin in local screen
coordinates.yOrigin
- Y component of the texture origin in local screen
coordinates.dux
- Number of u points to skip in the texture per x point on
screen (15.16 fixed point).dvx
- Number of v points to skip in the texture per x point on
screen (15.16 fixed point).duy
- Number of u points to skip in the texture per y point on
screen (15.16 fixed point).dvy
- Number of v points to skip in the texture per y point on
screen (15.16 fixed point).textureData
- Non-null bitmap to be used as a texture.
IllegalArgumentException
- If the data is malformed. For example,
the values in offsets is negative or not in increasing order, there are
fewer than 2 points in a single path, the values in offsets index outside
the points arrays, the values in pointTypes are invalid, or offsets is
null and xPts and yPts are not the same length.
IllegalArgumentException
- If texture bitmap is null.
IllegalArgumentException
- If texture bitmap is empty, i.e. width or height is zero.public int drawTextOnPath(StringBuffer aText, int aOffset, int aLength, int aOriginX, int aOriginY, int[] aXPoints, int[] aYPoints, byte[] aPointTypes, int[] aContourStarts, DrawTextParam aParam, TextMetrics aMetrics)
This method draws the text along a path made up of straight line segments and curves. The curves are quadratic or cubic Bezier splines. A path is made up of one or more separate contours.
Note that each non-null array parameter must be a different array.
The coordinates of the path are pixels, relative to a specified origin. To use absolute path coordinates supply an origin of (0,0).
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aOriginX
- The x part of the origin of the path coordinate system.aOriginY
- The y part of the origin of the path coordinate system.aXPoints
- An array of x coordinates for the path.aYPoints
- An array of y coordinates for the path.aPointTypes
- If non-null, an array of point types. If it is null,
or if it contains fewer values than the points arrays, missing values
are taken to be on-curve points. Each point type must be either
Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
, or
Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
.aContourStarts
- If non-null, an array of indexes of contour (sub-path) starts.
Each contour contains all the points from aContourStarts[N] to aContourStarts[N+1]-1,
except for the last contour, which contains all remaining points.aParam
- Text drawing parameters. If null, use default parameters.aMetrics
- If not null, this parameter receives the metrics of the
text drawn.
IllegalArgumentException
- or NullPointerException.public int drawTextOnPath(String aText, int aOffset, int aLength, int aOriginX, int aOriginY, int[] aXPoints, int[] aYPoints, byte[] aPointTypes, int[] aContourStarts, DrawTextParam aParam, TextMetrics aMetrics)
This method draws the text along a path made up of straight line segments and curves. The curves are quadratic or cubic Bezier splines. A path is made up of one or more separate contours.
Note that each non-null array parameter must be a different array.
The coordinates of the path are pixels, relative to a specified origin. To use absolute path coordinates supply an origin of (0,0).
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aOriginX
- The x part of the origin of the path coordinate system.aOriginY
- The y part of the origin of the path coordinate system.aXPoints
- An array of x coordinates for the path.aYPoints
- An array of y coordinates for the path.aPointTypes
- If non-null, an array of point types. If it is null,
or if it contains fewer values than the points arrays, missing values
are taken to be on-curve points. Each point type must be either
Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
, or
Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
aContourStarts
- If non-null, an array of indexes of contour (sub-path) starts.
Each contour contains all the points from aContourStarts[N] to aContourStarts[N + 1] - 1,
except for the last contour, which contains all remaining points.aParam
- Text drawing parameters. If null, use default parameters.aMetrics
- If non-null, this parameter receives the metrics of the text drawn.
IllegalArgumentException
- or NullPointerException.public int drawTextOnPath(char[] aText, int aOffset, int aLength, int aOriginX, int aOriginY, int[] aXPoints, int[] aYPoints, byte[] aPointTypes, int[] aContourStarts, DrawTextParam aParam, TextMetrics aMetrics)
This method draws the text along a path made up of straight line segments and curves. The curves are quadratic or cubic Bezier splines. A path is made up of one or more separate contours.
Note that each non-null array parameter must be a different array.
The coordinates of the path are pixels, relative to a specified origin. To use absolute path coordinates supply an origin of (0,0).
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aOriginX
- The x part of the origin of the path coordinate system.aOriginY
- The y part of the origin of the path coordinate system.aXPoints
- An array of x coordinates for the path.aYPoints
- An array of y coordinates for the path.aPointTypes
- If non-null, an array of point types. If it is null,
or if it contains fewer values than the points arrays, missing values
are taken to be on-curve points. Each point type must be either
Graphics.CURVEDPATH_END_POINT
,
Graphics.CURVEDPATH_QUADRATIC_BEZIER_CONTROL_POINT
, or
Graphics.CURVEDPATH_CUBIC_BEZIER_CONTROL_POINT
aContourStarts
- If non-null, an array of indexes of contour (sub-path) starts.
Each contour contains all the points from aContourStarts[N] to aContourStarts[N + 1] - 1,
except for the last contour, which contains all remaining points.aParam
- Text drawing parameters. If null, use default parameters.aMetrics
- If non-null, this parameter receives the metrics of the text drawn.
IllegalArgumentException
- or NullPointerException.public void drawLine(int x1, int y1, int x2, int y2)
Use this method to draw a line; you specify coordinates for the endpoints of the line.
x1
- Horizontal position of the line's starting point.y1
- Vertical position of the line's starting point.x2
- Horizontal position of the line's ending point.y2
- Vertical position of the line's ending point.public void drawPoint(int x, int y)
This method draws the pixel located at a coordinate you specify.
x
- Horizontal position of the point to draw.y
- Vertical position of the point to draw.public void drawRect(int x, int y, int width, int height)
Use this method to draw a rectangle. You specify the top and left
edges of the rectangle, and its width and height. This method draws the
right edge of the rectangle at (x+width-1)
, the bottom edge
at (y+height-1)
. The resulting rectangle will thus have an
area of (width * height)
.
If you pass in a zero or negative value for either the height or width, this method draws nothing.
x
- Left edge of the rectangle.y
- Top edge of the rectangle.width
- Width of the rectangle.height
- Height of the rectangle.public void drawRoundRect(int x, int y, int width, int height, int arcWidth, int arcHeight)
Use this method to draw a rectangle with rounded edges. You specify
the top and left edges of the rectangle, and its width and height. This
method draws the right edge of the rectangle at (x+width-1)
,
the bottom edge at (y+height-1)
. The resulting rectangle
will thus have an area, assuming no rounded corners, of
width * height
.
If you pass in a zero or negative value for either the height or width, this method draws nothing.
Use the arcWdith and arcHeight parameters to describe the arcs used to round off the four corners.
To apply anti-aliasing to the rounded corners, enable the drawing style Graphics.DRAWSTYLE_AALINES (see @setDrawingStyle)
x
- Left edge of the rectangle.y
- Top edge of the rectangle.width
- Width of the rectangle.height
- Height of the rectangle.arcWidth
- Width of arc used to round the four corners.arcHeight
- Height of arc used to round the four corners.public void drawRoundRect(int x, int y, int width, int height, int roundedCorners, int arcWidth, int arcHeight)
The home corner coordinates you provide locate the top left corner of the rectangle you want to draw.
If you want to use anti-aliasing for drawing, use
Graphics.setDrawingStyle(int, boolean)
with Graphics.DRAWSTYLE_ANTIALIASED
.
You specify the curvature for rounded corners by giving the height and width of an ellipical curve's quadrant (the quadrant of the ellipse chosen is the associated quadrant of the rectangle to draw--thus the top right quadrant of the ellipse gets used as the template for the curve of the top right quadrant of the rectangle to draw). If you want the rectangle's corner to be evenly rounded, you specify an ellipse with equal height and width (i.e. you describe a circle as the curvature template).
x
- Distance from left edge of the rectangle's home corner.y
- Distance from top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than one.height
- Vertical size of the rectangle; must be greater than one.roundedCorners
- Rounded corners bitmask value indicating which
corners to round (mask of the various *_ROUNDED_RECT_CORNER constants).arcWidth
- Width of the ellipse providing the arc segments used to
round the corners; must be greater than zero and less than the
rectangle's total width.arcHeight
- Height of the ellipse providing the arc segments used to
round the corners; must be greater than zero, and less than the rectangle's
total height.
IllegalArgumentException
- Thrown if you provide a width or height
less than one, or if the provided arc specifications are malformed
(height or width less than zero or greater than the rect's associated
dimension).public void drawRGB(int[] data, int offset, int scanLength, int x, int y, int width, int height)
data
- Color data to use, of the form 0x00RRGGBB.offset
- Offset into the data to start drawing from.scanLength
- Width of a scanline within the data.x
- Left edge of rectangle.y
- Top edge of the rectangle.width
- Width of the rectangle.height
- Height of the rectangle.
NullPointerException
- If 'data' is null.
ArrayIndexOutOfBoundsException
- If the data parameters are invalid.public int drawText(char aChar, int aX, int aY, int aFlags, int aWidth)
aChar
- The character to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.aWidth
- The width in pixels. The text is aligned within this width, and
truncated if its inked pixels bounds or x advance exceed aWidth. The value -1
causes the actual width of the text to be used, and forces left alignment.
public int drawText(String aText, int aX, int aY)
aText
- The text to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.
public int drawText(String aText, int aX, int aY, int aFlags)
aText
- The text to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.
public int drawText(String aText, int aX, int aY, int aFlags, int aWidth)
aText
- The text to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.aWidth
- The width in pixels. The text is aligned within this width, and
truncated if its inked pixels bounds or x advance exceed aWidth. The value -1
causes the actual width of the text to be used, and forces left alignment.
public int drawText(byte[] aText, int aOffset, int aLength, int aX, int aY, int aFlags, int aWidth)
Each byte is a single Unicode code point in the range 0...255. This method does not support UTF8 or any other encoding. To draw characters outside this range use a drawText method that accepts a char array or a String.
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The length of the text (number of elements in the array) to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.aWidth
- The width in pixels. The text is aligned within this width, and
truncated if its inked pixels bounds or x advance exceed aWidth. The value -1
causes the actual width of the text to be used, and forces left alignment.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public int drawText(char[] aText, int aOffset, int aLength, int aX, int aY, int aFlags, int aWidth)
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The length of the text (number of elements in the array) to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.aWidth
- The width in pixels. The text is aligned within this width, and
truncated if its inked pixels bounds or x advance exceed aWidth. The value -1
causes the actual width of the text to be used, and forces left alignment.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public int drawText(String aText, int aOffset, int aLength, int aX, int aY, int aFlags, int aWidth)
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.aWidth
- The width in pixels. The text is aligned within this width, and
truncated if its inked pixels bounds or x advance exceed aWidth. The value -1
causes the actual width of the text to be used, and forces left alignment.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public int drawText(StringBuffer aText, int aOffset, int aLength, int aX, int aY, int aFlags, int aWidth)
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aFlags
- A combination of constant drawing position flags.aWidth
- The width in pixels. The text is aligned within this width, and
truncated if its inked pixels bounds or x advance exceed aWidth. The value -1
causes the actual width of the text to be used, and forces left alignment.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public int drawText(String aText, int aOffset, int aLength, int aX, int aY, DrawTextParam aParam, TextMetrics aMetrics)
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aParam
- Text drawing parameters. If null, use default parameters.aMetrics
- If non-null, this parameter receives the metrics of the text drawn.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public int drawText(StringBuffer aText, int aOffset, int aLength, int aX, int aY, DrawTextParam aParam, TextMetrics aMetrics)
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The number of characters to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aParam
- Text drawing parameters. If null, use default parameters.aMetrics
- If non-null, this parameter receives the metrics of the text drawn.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public int drawText(char[] aText, int aOffset, int aLength, int aX, int aY, DrawTextParam aParam, TextMetrics aMetrics)
aText
- The text to draw.aOffset
- The start index of the text.aLength
- The length of the text (number of elements in the array) to draw.aX
- The horizontal position of the drawing anchor in pixels.aY
- The vertical position of drawing anchor in pixels.aParam
- Text drawing parameters. If null, use default parameters.aMetrics
- If non-null, this parameter receives the metrics of the text drawn.
IndexOutOfBoundsException
- If the values of aOffset and aLength
cause an element outside the array aText to be accessed.public void fillArc(int x, int y, int width, int height, int startAngle, int arcAngle)
The center of the filled arc is the center of a retangle whose origin
is (x,y)
and whose size is specified by the
width
and height
parameters.
The arc begins at startAngle
and extends for
arcAngle
degrees, using the current draw color. The drawing
algorithm assumes that the 0 degree position is in the center of the
right edge of the rectangle. The direction of the arc drawn depends on
the relative values of startAngle
and arcAngle
:
(startAngle < arcAngle)
, this method fills the
arc in a counterclockwise direction.
(startAngle > arcAngle)
, this method fills the
arc in a clockwise direction.
The resulting filled region consist of the wedge bounded by the arc
segment as if drawn by drawArc()
, the radius extending from
the center to this arc at startAngle
degrees, and radius
extending from the center to this arc at
(startAngle+arcAngle)
degrees.
If either width or height is less than zero, this method draws nothing.
The angles are specified relative to the non-square extents of the bounding rectangle such that 45 degrees always falls on the line from the center of the ellipse to the upper right corner of the bounding rectangle. As a result, if the bounding rectangle is noticeably longer in one axis than the other, the angles to the start and end of the arc segment will be skewed farther along the longer axis of the bounds. ATTENTION: This method doesn't support transformations specified in the setTransformation method.
x
- Horizontal coordinate of the arc's starting position.y
- Vertical coordinate of the arc's starting position.width
- Width of rectangle containing the filled arc.height
- Height of rectangle containing the filled arc.startAngle
- Angle position at which to commence drawing the edge of
the arc.arcAngle
- Angular extent of the arc, relative to the start angle.public void fillEllipse(int cx, int cy, int px, int py, int qx, int qy, int startAngle, int arcAngle)
Fills an ellipse with the specified endpoints P = (px, py) and Q = (qx, qy) of two conjugate diameters of the ellipse. The endpoints are specified as absolute coordinates.
This example shows an ellipse with the aligned p and q points.
This example shows how the p and q points can be used to draw a non-aligned ellipse.
cx
- X-ordinate of the ellipse centre. cx is one of the coordinates of the center point of the ellipse.cy
- Y-ordinate of the ellipse centre. cy is one of the coordinates of the center point of the ellipse.px
- X-ordinate of the point P. P is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the p point defines the x-axis radius.py
- Y-ordinate of the point P. P is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the p point defines the x-axis radius.qx
- X-ordinate of the point Q. Q is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the q point defines the y-axis radius.qy
- Y-ordinate of the point Q. Q is one of the coordinates of the tangents of a parallelogram
that bounds the ellipse. By convention, if the ellipse is aligned with the screen axes,
the q point defines the y-axis radius.startAngle
- Arc start angle. Drawing starts at the angular position defined by the start angle
(clockwise with zero degrees being the x-axis and x left, y down) and ends at an angular position
equal to the start angle plus the arc angle. For example, if you set the start angle to 90 degrees
and the arc angle to 90 degrees, the ¼ ellipse starts at the y axis and continues to the x axis.arcAngle
- Angular extent of the arc, relative to the start angle.public void fillRect(int x, int y, int width, int height)
Note that if global alpha is set or if the fill color includes alpha then the rectangle color will be blended onto the content on the target surface.
Use this method to fill a rectangle. You specify the top and left
edges of the rectangle, and its width and height. This method paints the
right edge of the rect at (x+width-1)
, the bottom edge at
(y+height-1)
. The resulting rectangle will thus have an area
of width * height
.
If you pass in a zero or negative value for either the height or width, this method draws nothing.
x
- Left edge of the rectangle.y
- Top edge of the rectangle.width
- Width of the rectangle.height
- Height of the rectangle.public void fillRoundRect(int x, int y, int width, int height, int arcWidth, int arcHeight)
Use this method to fill a rectangle with rounded edges. You specify
the top and left edges of the rectangle, and its width and height. This
method draws the right edge of the filled rectangle at
(x+width-1)
, the bottom edge at
(y+height-1)
. The resulting rectangle will thus have an
area, assuming no rounded corners, of width * height
.
If you pass in a zero or negative value for either the height or width, this method draws nothing.
Use the arcWidth
and arcHeight
parameters
to describe the arcs used to round off the four corners.
x
- Left edge of the rectangle.y
- Top edge of the rectangle.width
- Width of the rectangle.height
- Height of the rectangle.arcWidth
- Width of arc used to round the four corners.arcHeight
- Height of arc used to round the four corners.public void getAbsoluteClippingRect(XYRect clip)
Use this method to retrieve, into a provided XYRect object, the absolute coordinates of the current clipping region.
Since the out parameter contains only a copy of the clipping region, altering its contents has no effect on the current clipping region.
clip
- Clipping region is returned in this parameter.public int getBackgroundColor()
public XYRect getClippingRect()
The returned XYRect
is owned by this graphics object and
you should not change it. Instead, use this class's various
push
and pop
methods to change the extent of
the current clipping region.
public int getContextStackSize()
public int getColor()
public void getDrawingOffset(XYPoint offset)
The drawing offset is the point, offset from the top left corner of the screen, which drawing operations use as their origin point.
offset
- Drawing offset is returned in this paramater.public int getGlobalAlpha()
public int getNearestColor(int color)
color
- the desired color (in 0x00RRGGBB format, the high-order byte is ignored)
public static int getNumColors()
public int getStipple()
public Font getFont()
public static int getScreenHeight()
public static int getScreenHorizontalResolution()
public static int getScreenVerticalResolution()
public static int getScreenWidth()
public void invert(int x, int y, int width, int height)
This method performs a one's complement operation on each pixel in your specified region.
x
- Left edge of the region.y
- Top edge of the region.width
- Width of the region.height
- Height of the region.public void invert(XYRect rect)
This method performs a one's complement operation on each pixel in your specified region.
rect
- Region to invert.public void popContext()
Use this method to pop off the context stack the last context pushed.
public boolean pushRegion(int x, int y, int width, int height, int xScroll, int yScroll)
The clipping region is updated by intersecting with the previous
clipping region. The drawing offset is adjusted by the value of the
region origin. You can also specify an (optional) additional scroll
offset with the xScroll
and yScroll
parameters.
This method is suitable for pushing a context for drawing into a subregion.
x
- Left edge of the region.y
- Top edge of the region.width
- Width of the region.height
- Height of the region.xScroll
- Optional, additional scroll offset.yScroll
- Optional, additional scroll offset.public boolean pushRegion(XYRect region)
The clipping region is updated by intersecting with the previous clipping region. The drawing offset is adjusted by the value of the region origin.
This method is suitable for pushing a context for drawing into a subregion.
region
- New drawing region rectangle in local coordinates.public boolean pushRegion(XYRect region, int xScroll, int yScroll)
This method behaves exactly like Graphics.pushRegion(XYRect)
, except
you can also specify an (optional) additional scroll offset with the
xScroll
and yScroll
parameters.
region
- New drawing region in local coordinates.xScroll
- Optional, additional horizontal scroll offset.yScroll
- Optional, additional vertical scroll offset.public boolean pushContext(XYRect clip, int xOffset, int yOffset)
This clipping region is updated by intersecting with the previous
clipping region. Unlike Graphics.pushRegion(int, int, int, int, int, int)
, the drawing offset is
not adjusted by the value of the region origin. You can also
specify an additional drawing offset update by using the
xOffset
and yOffset
parameters.
To setup a subregion for local drawing pushRegion
should
be used.
clip
- New clipping region in local coordinates.xOffset
- Optional, additional horizontal scroll offset.yOffset
- Optional, additional vertical scroll offset.public boolean pushContext(int x, int y, int width, int height, int xOffset, int yOffset)
This clipping region is updated by intersecting with the previous
clipping region. Unlike Graphics.pushRegion(int, int, int, int, int, int)
, the drawing offset is
not adjusted by the value of the region origin. You can also
specify an additional drawing offset update by using the
xOffset
and yOffset
parameters.
To setup a subregion for local drawing, Graphics.pushRegion(int, int, int, int, int, int)
should be
used.
x
- Left edge of clipping region.y
- Top edge of clipping region.width
- Width in pixels of clipping region.height
- Height in pixels of clipping region.xOffset
- Optional, additional horizontal scroll offset.yOffset
- Optional, additional vertical scroll offset.public void translate(int x, int y)
The drawing offset is updated by adding the x and y offsets.
x
- Horizontal offset to add to the current x drawing offset.y
- Vertical offset to add to the current y drawing offset.public int getTranslateX()
public int getTranslateY()
public boolean isDrawingStyleSet(int drawStyle)
drawStyle
- Graphics drawing style to be checked.
public void setDrawingStyle(int drawStyle, boolean on)
drawStyle
- Graphics drawing style to turn on or off.on
- True to turn on the specified style, false to turn it off.public void setColor(int RGB)
All subsequent rendering will be done in this color (more precisely, rendering will be done in a displayable color that is nearest to the color you specify).
RGB
- Color to use, of the form 0x00RRGGBB.public void setGlobalAlpha(int alpha)
Be sure to reset the global alpha value when appropriate since all subsequent operations are done using the value specified. Global alpha is stored on the stack so popContext will restore it to the previous value.
Note that alpha
will be clamped to the range 0-255.
alpha
- Alpha value to use, from 0 (fully transparent) to 255 (fully opaque).public void setStipple(int mask)
All subsequent line rendering operations will be done with this stipple value. The stipple value is a 32 bit bitmask where a 1 indicates a pixel should be drawn and a 0 indicates the destination pixel should be left as is. The mask is cycled through as the line is drawn.
mask
- The stipple mask to use for line drawing.public void setBackgroundColor(int RGB)
RGB
- Color to use, of the form 0x00RRGGBB.public void setFont(Font font)
Subsequent text rendering uses this font.
font
- New font.
NullPointerException
- If font is null.public static boolean isColor()
public void drawGradientFilledRect(XYRect rect, int startColor, int endColor)
This is a convenience method wrapping
drawGradientFill(rect,startColor,endColor,false)
.
rect
- Rectangle to draw; must not be null and must have
dimensions greater than zero.startColor
- Color to start with.endColor
- Color to end with.
IllegalArgumentException
- Thrown if the provided rect is malformed
(either null, or with a height or width of zero or less).public void drawGradientFilledRect(XYRect rect, int startColor, int endColor, boolean drawBorder)
The gradient fill is a linear gradient from the top edge of the rectangle to the bottom edge.
If you want to use dithered shading, use Graphics.setDrawingStyle(int, boolean)
with Graphics.DRAWSTYLE_DITHERED_SHADING
.
rect
- Dimensions and placement of the rectangle to draw; must not
be null and must have dimensions greater than zero.startColor
- Color to start with, at the top edge of the rectangle.endColor
- Color to transform into, at the bottom edge of the
rectangle.drawBorder
- True to draw a bordered rectangle; false to draw the
rect with no border. The border stroke is one pixel wide; the border
color is the default foreground color set with Graphics.setColor(int)
.
IllegalArgumentException
- Thrown if the provided rect is malformed
(either null, or with a height or width of zero or less).public void drawGradientFilledRect(int x, int y, int width, int height, int startColor, int endColor)
This is a convenience method wrapping
drawGradientFilledRect(x,y,width,height,startColor,endColor,false)
.
x
- Distance from left edge of the rectangle's home corner.y
- Distance from the top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than zero.height
- Vertical size of the rectangle; must be greater than zero.startColor
- Color to start with.endColor
- Color to end with.
IllegalArgumentException
- Thrown if you provide a width or height
of zero or less.public void drawGradientFilledRect(int x, int y, int width, int height, int startColor, int endColor, boolean drawBorder)
The home corner coordinates you provide locate the top left corner of the rectangle you want to draw.
The gradient fill is a linear gradient from the top edge of the rectangle to the bottom edge.
If you want to use dithered shading, use Graphics.setDrawingStyle(int, boolean)
with Graphics.DRAWSTYLE_DITHERED_SHADING
.
x
- Distance from left edge of the rectangle's home corner.y
- Distance from top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than zero.height
- Vertical size of the rectangle; must be greater than zero.startColor
- Color to start with, at the top edge of the rectangle.endColor
- Color to transform into, at the bottom edge of the
rectangle.drawBorder
- True to draw a bordered rectangle; false to draw the
rect with no border. The border stroke is one pixel wide; the border
color is the default foreground color set with Graphics.setColor(int)
.
IllegalArgumentException
- Thrown if you provide a width or height
of zero or less.public void drawGradientFilledRoundedRect(XYRect rect, int startColor, int endColor, int arcWidth, int arcHeight)
This is a convenience method wrapping
drawGradientFilledRoundedRec(rect,startColor,endColor,false,ALL_ROUNDED_RECT_CORNERS,arcWidth,arcHeight)
.
rect
- Rectangle to draw; must not be null and must have dimensions
greater than zero.startColor
- Color to start with.endColor
- Color to end with.arcWidth
- Width of ellipse for rounding; must be between zero and
the rect width (inclusive).arcHeight
- Height of ellipse for rounding; must be between zero and
the rect height (inclusive).
IllegalArgumentException
- Thrown if the provided rect is malformed
(either null, or with a height or width of zero or less), or if the
provided arc specifications are malformed (height or width less than zero,
or greater than the rect's associated dimension).public void drawGradientFilledRoundedRect(XYRect rect, int startColor, int endColor, boolean drawBorder, int arcWidth, int arcHeight)
This is a convenience method wrapping
drawGradientFilledRoundedRec(rect,startColor,endColor,drawBorder,ALL_ROUNDED_RECT_CORNERS,arcWidth,arcHeight)
.
rect
- Rectangle to draw; must not be null and must have dimensions
greater than zero.startColor
- Color to start with.endColor
- Color to end with.drawBorder
- True to draw a border; false to draw the rect without a border.arcWidth
- Width of ellipse for rounding; must be between zero and
the rect width (inclusive).arcHeight
- Height of ellipse for rounding; must be between zero and
the rect height (inclusive).
IllegalArgumentException
- Thrown if the provided rect is malformed
(either null, or with a height or width of zero or less), or if the
provided arc specifications are malformed (height or width less than zero
or greater than the rect's associated dimension).public void drawGradientFilledRoundedRect(XYRect rect, int startColor, int endColor, int roundedCorners, int arcWidth, int arcHeight)
This is a convenience method wrapping
drawGradientFilledRoundedRec(rect,startColor,endColor,false,roundedCorners,arcWidth,arcHeight)
.
rect
- Rectangle to draw; must not be null and must have dimensions
greater than zero.startColor
- Color to start with.endColor
- Color to end with.roundedCorners
- Mask of *_ROUNDED_RECT_CORNER constants to mark
corners to round.arcWidth
- Width of ellipse for rounding; must be between zero and
the rect width (inclusive).arcHeight
- Height of ellipse for rounding; must be between zero and
the rect height (inclusive).
IllegalArgumentException
- Thrown if the provided rect is malformed
(either null, or with a height or width of zero or less), or if the
provided arc specifications are malformed (height or width of less than zero
or greater than the rect's associated dimension).public void drawGradientFilledRoundedRect(XYRect rect, int startColor, int endColor, boolean drawBorder, int roundedCorners, int arcWidth, int arcHeight)
The gradient fill is a linear gradient from the top edge of the
rectangle to the bottom edge. If you want to use dithered shading, use
Graphics.setDrawingStyle(int, boolean)
with Graphics.DRAWSTYLE_DITHERED_SHADING
.
You specify the curvature for rounded corners by giving the height and width of an elliptical curve's quadrant (the quadrant of the ellipse chosen is the associated quadrant of the rectangle to draw--thus the top right quadrant of the ellipse gets used as the template for the curve of the top right quadrant of the rectangle to draw). If you want the rectangle's corner to be evenly rounded, you specify an ellipse with equal height and width (i.e. you describe a circle as the curvature template).
rect
- Dimensions and placement of the rectangle to draw; must not
be null and must have dimensions greater than zero.startColor
- Color to start with, at the top edge of the rectangle.endColor
- Color to transform into, at the bottom edge of the
rectangle.drawBorder
- True to draw a bordered rectangle; false to draw the
rect with no border. The border stroke is one pixel wide; the border
color is the default foreground color set with Graphics.setColor(int)
.roundedCorners
- Rounded corners bitmask value indicating which
corners to round (mask of the various *_ROUNDED_RECT_CORNER constants).arcWidth
- Width of the ellipse providing the arc segments used to
round the corners; must be between zero and the rectangle's total width
(inclusive).arcHeight
- Height of the ellipse providing the arc segments used to
round the corners; must be between zero and the rectangle's total height
(inclusive).
IllegalArgumentException
- Thrown if the provided rect is malformed
(either null, or with a height or width of zero or less), or if the
provided arc specifications are malformed (height or width less than zero,
or greater than the rect's associated dimension).public void drawGradientFilledRoundedRect(int x, int y, int width, int height, int startColor, int endColor, int arcWidth, int arcHeight)
This is a convenience method wrapping
drawGradientFilledRoundedRec(x,y,width,height,startColor,endColor,false,ALL_ROUNDED_RECT_CORNERS,arcWidth,arcHeight)
.
x
- Distance from left edge of the rectangle's home corner.y
- Distance from top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than zero.height
- Vertical size of the rectangle; must be greater than zero.startColor
- Color to start with.endColor
- Color to end with.arcWidth
- Width of ellipse for rounding; must be between zero and
the rect width (inclusive).arcHeight
- Height of ellipse for rounding; must be between zero and
the rect height (inclusive).
IllegalArgumentException
- Thrown if you provide a width or height
of zero or less, or if the provided arc specifications are malformed
(height or width less than zero, or greater than the rect's associated
dimension).public void drawGradientFilledRoundedRect(int x, int y, int width, int height, int startColor, int endColor, boolean drawBorder, int arcWidth, int arcHeight)
This is a convenience method wrapping
drawGradientFilledRoundedRec(x,y,width,height,startColor,endColor,drawBorder,ALL_ROUNDED_RECT_CORNERS,arcWidth,arcHeight)
.
x
- Distance from left edge of the rectangle's home corner.y
- Distance from top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than zero.height
- Vertical size of the rectangle; must be greater than zero.startColor
- Color to start with.endColor
- Color to end with.drawBorder
- True to draw a border; false to draw the rect without a border.arcWidth
- Width of ellipse for rounding; must be between zero and
the rect width (inclusive).arcHeight
- Height of ellipse for rounding; must be between zero and
the rect height (inclusive).
IllegalArgumentException
- Thrown if you provide a width or height
of zero or less, or if the provided arc specifications are malformed
(height or width less than zero, or greater than the rect's associated
dimension).public void drawGradientFilledRoundedRect(int x, int y, int width, int height, int startColor, int endColor, int roundedCorners, int arcWidth, int arcHeight)
This is a convenience method wrapping
drawGradientFilledRoundedRec(x,y,width,height,startColor,endColor,false,roundedCorners,arcWidth,arcHeight)
.
x
- Distance from left edge of the rectangle's home corner.y
- Distance from top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than zero.height
- Vertical size of the rectangle; must be greater than zero.startColor
- Color to start with.endColor
- Color to end with.roundedCorners
- Mask of *_ROUNDED_RECT_CORNER constants to mark
corners to round.arcWidth
- Width of ellipse for rounding; must be between zero and
the rect width (inclusive).arcHeight
- Height of ellipse for rounding; must be between zero and
the rect height (inclusive).
IllegalArgumentException
- Thrown if you provide a width or height
of zero or less, or if the provided arc specifications are malformed
(height or width less than zero, or greater than the rect's associated
dimension).public void drawGradientFilledRoundedRect(int x, int y, int width, int height, int startColor, int endColor, boolean drawBorder, int roundedCorners, int arcWidth, int arcHeight)
The home corner coordinates you provide locate the top left corner of the rectnagle you want to draw.
The gradient fill is a linear gradient from the top edge of the
rectangle to the bottom edge. If you want to use dithered shading, use
Graphics.setDrawingStyle(int, boolean)
with Graphics.DRAWSTYLE_DITHERED_SHADING
.
You specify the curvature for rounded corners by giving the height and width of an elliptical curve's quadrant (the quadrant of the ellipse chosen is the associated quadrant of the rectangle to draw--thus the top right quadrant of the ellipse gets used as the template for the curve of the top right quadrant of the rectangle to draw). If you want the rectangle's corner to be evenly rounded, you specify an ellipse with equal height and width (i.e. you describe a circle as the curvature template).
x
- Distance from left edge of the rectangle's home corner.y
- Distance from top edge of the rectangle's home corner.width
- Horizontal size of the rectangle; must be greater than zero.height
- Vertical size of the rectangle; must be greater than zero.startColor
- Color to start with, at the top edge of the rectangle.endColor
- Color to transform into, at the bottom edge of the
rectangle.drawBorder
- True to draw a bordered rectangle; false to draw the
rect with no border. The border stroke is one pixel wide; the border
color is the default foreground color set with Graphics.setColor(int)
.roundedCorners
- Rounded corners bitmask value indicating which
corners to round (mask of the various *_ROUNDED_RECT_CORNER constants).arcWidth
- Width of the ellipse providing the arc segments used to
round the corners; must be between zero and the rectangle's total width
(inclusive).arcHeight
- Height of the ellipse providing the arc segments used to
round the corners; must be between zero and the rectangle's
total height (inclusive).
IllegalArgumentException
- Thrown if you provide a width or height
of zero or less, or if the provided arc specifications are malformed
(height or width less than zero, or greater than the rect's associated
dimension).
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