javafx.scene.canvas

Class GraphicsContext

java.lang.Object

javafx.scene.canvas.GraphicsContext

public final class GraphicsContext
extends java.lang.Object

This class is used to issue draw calls to a Canvas using a buffer.

Each call pushes the necessary parameters onto the buffer where it is executed on the image of the Canvas node.

A Canvas only contains one GraphicsContext, and only one buffer. If it is not attached to any scene, then it can be modified by any thread, as long as it is only used from one thread at a time. Once a Canvas node is attached to a scene, it must be modified on the JavaFX Application Thread.

Calling any method on the GraphicsContext is considered modifying its corresponding Canvas and is subject to the same threading rules.

A GraphicsContext also manages a stack of state objects that can be saved or restored at anytime.

Example:

import javafx.scene.*;
import javafx.scene.paint.*;
import javafx.scene.canvas.*;

Group root = new Group();
Scene s = new Scene(root, 300, 300, Color.BLACK);

final Canvas canvas = new Canvas(250,250);
GraphicsContext gc = canvas.getGraphicsContext2D();

gc.setFill(Color.BLUE);
gc.fillRect(75,75,100,100);

root.getChildren().add(canvas);
 

Since:

2.2

Method Summary

Methods

Modifier and Type	Method and Description
void	appendSVGPath(java.lang.String svgpath) Appends an SVG Path string to the current path.
void	applyEffect(Effect e) Applies the given effect to the entire canvas.
void	arc(double centerX, double centerY, double radiusX, double radiusY, double startAngle, double length) Adds path elements to the current path to make an arc that uses Euclidean degrees.
void	arcTo(double x1, double y1, double x2, double y2, double radius) Adds segments to the current path to make an arc.
void	beginPath() Starts a Path
void	bezierCurveTo(double xc1, double yc1, double xc2, double yc2, double x1, double y1) Adds segments to the current path to make a cubic bezier curve.
void	clearRect(double x, double y, double w, double h) Clears a portion of the canvas with a transparent color value.
void	clip() Clips using the current path
void	closePath() Closes the path.
void	drawImage(Image img, double x, double y) Draws an image at the given x, y position using the width and height of the given image.
void	drawImage(Image img, double x, double y, double w, double h) Draws an image into the given destination rectangle of the canvas.
void	drawImage(Image img, double sx, double sy, double sw, double sh, double dx, double dy, double dw, double dh) Draws the current source rectangle of the given image to the given destination rectangle of the Canvas.
void	fill() Fills the path with the current fill paint.
void	fillArc(double x, double y, double w, double h, double startAngle, double arcExtent, ArcType closure) Fills an arc using the current fill paint.
void	fillOval(double x, double y, double w, double h) Fills an oval using the current fill paint.
void	fillPolygon(double[] xPoints, double[] yPoints, int nPoints) Fills a polygon with the given points using the currently set fill paint.
void	fillRect(double x, double y, double w, double h) Fills a rectangle using the current fill paint.
void	fillRoundRect(double x, double y, double w, double h, double arcWidth, double arcHeight) Fills a rounded rectangle using the current fill paint.
void	fillText(java.lang.String text, double x, double y) Fills the given string of text at position x, y (0,0 at top left) with the current fill paint attribute.
void	fillText(java.lang.String text, double x, double y, double maxWidth) Fills text and includes a maximum width of the string.
Canvas	getCanvas() Gets the Canvas that the GraphicsContext is issuing draw commands to.
Effect	getEffect(Effect e) Gets a copy of the effect to be applied after the next draw call.
Paint	getFill() Gets the current fill attribute.
FillRule	getFillRule() Get the filling rule constant for determining the interior of the path.
Font	getFont() Gets the current Font.
double	getGlobalAlpha() Gets the current global alpha.
BlendMode	getGlobalBlendMode() Gets the global blend mode.
StrokeLineCap	getLineCap() Gets the current stroke line cap.
StrokeLineJoin	getLineJoin() Gets the current stroke line join.
double	getLineWidth() Gets the current line width.
double	getMiterLimit() Gets the current miter limit.
PixelWriter	getPixelWriter() Returns a PixelWriter object that can be used to modify the pixels of the Canvas associated with this GraphicsContext.
Paint	getStroke() Gets the current stroke.
TextAlignment	getTextAlign() Gets the current TextAlignment.
VPos	getTextBaseline() Gets the current Text Baseline.
Affine	getTransform() Returns a copy of the current transform.
Affine	getTransform(Affine xform) Returns a copy of the current transform.
boolean	isPointInPath(double x, double y) Returns true if the the given x,y point is inside the path.
void	lineTo(double x1, double y1) Adds segments to the current path to make a line at the given x,y coordinate.
void	moveTo(double x0, double y0) Issues a move command for the current path to the given x,y coordinate.
void	quadraticCurveTo(double xc, double yc, double x1, double y1) Adds segments to the current path to make a quadratic curve.
void	rect(double x, double y, double w, double h) Adds path elements to the current path to make a rectangle.
void	restore() Pops the state off of the stack, setting the following attributes to their value at the time when that state was pushed onto the stack.
void	rotate(double degrees) Rotates the current transform in degrees.
void	save() Saves the following attributes onto a stack.
void	scale(double x, double y) Scales the current transform by x, y.
void	setEffect(Effect e) Sets the effect to be applied after the next draw call, or null to disable effects.
void	setFill(Paint p) Sets the current fill attribute.
void	setFillRule(FillRule fillRule) Set the filling rule constant for determining the interior of the path.
void	setFont(Font f) Sets the current Font.
void	setGlobalAlpha(double alpha) Sets the global alpha of the current state.
void	setGlobalBlendMode(BlendMode op) Sets the global blend mode.
void	setLineCap(StrokeLineCap cap) Sets the current stroke line cap.
void	setLineJoin(StrokeLineJoin join) Sets the current stroke line join.
void	setLineWidth(double lw) Sets the current line width.
void	setMiterLimit(double ml) Sets the current miter limit.
void	setStroke(Paint p) Sets the current stroke.
void	setTextAlign(TextAlignment align) Defines horizontal text alignment, relative to the text x origin.
void	setTextBaseline(VPos baseline) Sets the current Text Baseline.
void	setTransform(Affine xform) Sets the current transform.
void	setTransform(double mxx, double myx, double mxy, double myy, double mxt, double myt) Sets the current transform.
void	stroke() Strokes the path with the current stroke paint.
void	strokeArc(double x, double y, double w, double h, double startAngle, double arcExtent, ArcType closure) Strokes an Arc using the current stroke paint.
void	strokeLine(double x1, double y1, double x2, double y2) Strokes a line using the current stroke paint.
void	strokeOval(double x, double y, double w, double h) Strokes a rectangle using the current stroke paint.
void	strokePolygon(double[] xPoints, double[] yPoints, int nPoints) Strokes a polygon with the given points using the currently set stroke paint.
void	strokePolyline(double[] xPoints, double[] yPoints, int nPoints) Draws a polyline with the given points using the currently set stroke paint attribute.
void	strokeRect(double x, double y, double w, double h) Strokes a rectangle using the current stroke paint.
void	strokeRoundRect(double x, double y, double w, double h, double arcWidth, double arcHeight) Strokes a rounded rectangle using the current stroke paint.
void	strokeText(java.lang.String text, double x, double y) draws the given string of text at position x, y (0,0 at top left) with the current stroke paint attribute.
void	strokeText(java.lang.String text, double x, double y, double maxWidth) Draws text with stroke paint and includes a maximum width of the string.
void	transform(Affine xform) Concatenates the input with the current transform.
void	transform(double mxx, double myx, double mxy, double myy, double mxt, double myt) Concatenates the input with the current transform.
void	translate(double x, double y) Translates the current transform by x, y.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getCanvas

public Canvas getCanvas()

Gets the Canvas that the GraphicsContext is issuing draw commands to. There is only ever one Canvas for a GraphicsContext.

Returns:

Canvas the canvas that this GraphicsContext is issuing draw commands to.

save

public void save()

Saves the following attributes onto a stack.

• Global Alpha
• Global Blend Operation
• Transform
• Fill Paint
• Stroke Paint
• Line Width
• Line Cap
• Line Join
• Miter Limit
• Number of Clip Paths
• Font
• Text Align
• Text Baseline
• Effect
• Fill Rule

This method does NOT alter the current state in any way. Also, not that the current path is not saved.

restore

public void restore()

Pops the state off of the stack, setting the following attributes to their value at the time when that state was pushed onto the stack. If the stack is empty then nothing is changed.

• Global Alpha
• Global Blend Operation
• Transform
• Fill Paint
• Stroke Paint
• Line Width
• Line Cap
• Line Join
• Miter Limit
• Number of Clip Paths
• Font
• Text Align
• Text Baseline
• Effect
• Fill Rule

translate

public void translate(double x,
             double y)

Translates the current transform by x, y.

Parameters:

x - value to translate along the x axis.

y - value to translate along the y axis.

scale

public void scale(double x,
         double y)

Scales the current transform by x, y.

Parameters:

x - value to scale in the x axis.

y - value to scale in the y axis.

rotate

public void rotate(double degrees)

Rotates the current transform in degrees.

Parameters:

degrees - value in degrees to rotate the current transform.

transform

public void transform(double mxx,
             double myx,
             double mxy,
             double myy,
             double mxt,
             double myt)

Concatenates the input with the current transform.

Parameters:

mxx - - the X coordinate scaling element of the 3x4 matrix

myx - - the Y coordinate shearing element of the 3x4 matrix

mxy - - the X coordinate shearing element of the 3x4 matrix

myy - - the Y coordinate scaling element of the 3x4 matrix

mxt - - the X coordinate translation element of the 3x4 matrix

myt - - the Y coordinate translation element of the 3x4 matrix

transform

public void transform(Affine xform)

Concatenates the input with the current transform. Only 2D transforms are supported. The only values used are the X and Y scaling, translation, and shearing components of a transform.

Parameters:

xform - The affine to be concatenated with the current transform.

setTransform

public void setTransform(double mxx,
                double myx,
                double mxy,
                double myy,
                double mxt,
                double myt)

Sets the current transform.

Parameters:

mxx - - the X coordinate scaling element of the 3x4 matrix

myx - - the Y coordinate shearing element of the 3x4 matrix

mxy - - the X coordinate shearing element of the 3x4 matrix

myy - - the Y coordinate scaling element of the 3x4 matrix

mxt - - the X coordinate translation element of the 3x4 matrix

myt - - the Y coordinate translation element of the 3x4 matrix

setTransform

public void setTransform(Affine xform)

Sets the current transform. Only 2D transforms are supported. The only values used are the X and Y scaling, translation, and shearing components of a transform.

Parameters:

xform - The affine to be copied and used as the current transform.

getTransform

public Affine getTransform(Affine xform)

Returns a copy of the current transform.

Parameters:

xform - A transform object that will be used to hold the result. If xform is non null, then this method will copy the current transform into that object. If xform is null a new transform object will be constructed. In either case, the return value is a copy of the current transform.

Returns:

A copy of the current transform.

getTransform

public Affine getTransform()

Returns a copy of the current transform.

Returns:

a copy of the transform of the current state.

setGlobalAlpha

public void setGlobalAlpha(double alpha)

Sets the global alpha of the current state.

Parameters:

alpha - value in the range 0.0-1.0. The value is clamped if it is out of range.

getGlobalAlpha

public double getGlobalAlpha()

Gets the current global alpha.

Returns:

the current global alpha.

setGlobalBlendMode

public void setGlobalBlendMode(BlendMode op)

Sets the global blend mode.

Parameters:

op - the BlendMode that will be set.

getGlobalBlendMode

public BlendMode getGlobalBlendMode()

Gets the global blend mode.

Returns:

the global BlendMode of the current state.

setFill

public void setFill(Paint p)

Sets the current fill attribute. This method affects the paint used for any method with "fill" in it. For Example, fillRect(...), fillOval(...).

Parameters:

p - The Paint to be used as the fill Paint.

getFill

public Paint getFill()

Gets the current fill attribute. This method affects the paint used for any method with "fill" in it. For Example, fillRect(...), fillOval(...).

Returns:

p The Paint to be used as the fill Paint.

setStroke

public void setStroke(Paint p)

Sets the current stroke.

Parameters:

p - The Paint to be used as the stroke Paint.

getStroke

public Paint getStroke()

Gets the current stroke.

Returns:

the Paint to be used as the stroke Paint.

setLineWidth

public void setLineWidth(double lw)

Sets the current line width.

Parameters:

lw - value in the range {0-positive infinity}, with any other value being ignored and leaving the value unchanged.

getLineWidth

public double getLineWidth()

Gets the current line width.

Returns:

value between 0 and infinity.

setLineCap

public void setLineCap(StrokeLineCap cap)

Sets the current stroke line cap.

Parameters:

cap - StrokeLineCap with a value of Butt, Round, or Square.

getLineCap

public StrokeLineCap getLineCap()

Gets the current stroke line cap.

Returns:

StrokeLineCap with a value of Butt, Round, or Square.

setLineJoin

public void setLineJoin(StrokeLineJoin join)

Sets the current stroke line join.

Parameters:

join - StrokeLineJoin with a value of Miter, Bevel, or Round.

getLineJoin

public StrokeLineJoin getLineJoin()

Gets the current stroke line join.

Returns:

StrokeLineJoin with a value of Miter, Bevel, or Round.

setMiterLimit

public void setMiterLimit(double ml)

Sets the current miter limit.

Parameters:

ml - miter limit value between 0 and positive infinity with any other value being ignored and leaving the value unchanged.

getMiterLimit

public double getMiterLimit()

Gets the current miter limit.

Returns:

the miter limit value in the range 0.0-positive infinity

setFont

public void setFont(Font f)

Sets the current Font.

Parameters:

f - the Font

getFont

public Font getFont()

Gets the current Font.

Returns:

the Font

setTextAlign

public void setTextAlign(TextAlignment align)

Defines horizontal text alignment, relative to the text x origin.

Let horizontal bounds represent the logical width of a single line of text. Where each line of text has a separate horizontal bounds.

Then TextAlignment is specified as:

• Left: the left edge of the horizontal bounds will be at x.
• Center: the center, halfway between left and right edge, of the horizontal bounds will be at x.
• Right: the right edge of the horizontal bounds will be at x.

Note: Canvas does not support line wrapping, therefore the text alignment Justify is identical to left aligned text.

Parameters:

align - TextAlignment with values of Left, Center, Right.

getTextAlign

public TextAlignment getTextAlign()

Gets the current TextAlignment.

Returns:

TextAlignment with values of Left, Center, Right, or Justify.

setTextBaseline

public void setTextBaseline(VPos baseline)

Sets the current Text Baseline.

Parameters:

baseline - VPos with values of Top, Center, Baseline, or Bottom

getTextBaseline

public VPos getTextBaseline()

Gets the current Text Baseline.

Returns:

VPos with values of Top, Center, Baseline, or Bottom

fillText

public void fillText(java.lang.String text,
            double x,
            double y)

Fills the given string of text at position x, y (0,0 at top left) with the current fill paint attribute.

Parameters:

text - the string of text.

x - position on the x axis.

y - position on the y axis.

strokeText

public void strokeText(java.lang.String text,
              double x,
              double y)

draws the given string of text at position x, y (0,0 at top left) with the current stroke paint attribute.

Parameters:

text - the string of text.

x - position on the x axis.

y - position on the y axis.

fillText

public void fillText(java.lang.String text,
            double x,
            double y,
            double maxWidth)

Fills text and includes a maximum width of the string. If the width of the text extends past max width, then it will be sized to fit.

Parameters:

text - the string of text.

x - position on the x axis.

y - position on the y axis.

maxWidth - maximum width the text string can have.

strokeText

public void strokeText(java.lang.String text,
              double x,
              double y,
              double maxWidth)

Draws text with stroke paint and includes a maximum width of the string. If the width of the text extends past max width, then it will be sized to fit.

Parameters:

text - the string of text.

x - position on the x axis.

y - position on the y axis.

maxWidth - maximum width the text string can have.

setFillRule

public void setFillRule(FillRule fillRule)

Set the filling rule constant for determining the interior of the path. The value must be one of the following constants: FillRile.EVEN_ODD or FillRule.NON_ZERO. The default value is FillRule.NON_ZERO.

Default value:

FillRule.NON_ZERO

getFillRule

public FillRule getFillRule()

Get the filling rule constant for determining the interior of the path. The default value is FillRule.NON_ZERO.

Returns:

current fill rule.

beginPath

public void beginPath()

Starts a Path

moveTo

public void moveTo(double x0,
          double y0)

Issues a move command for the current path to the given x,y coordinate.

Parameters:

x0 - the X position for the move to command.

y0 - the Y position for the move to command.

lineTo

public void lineTo(double x1,
          double y1)

Adds segments to the current path to make a line at the given x,y coordinate.

Parameters:

x1 - the X coordinate of the ending point of the line.

y1 - the Y coordinate of the ending point of the line.

quadraticCurveTo

public void quadraticCurveTo(double xc,
                    double yc,
                    double x1,
                    double y1)

Adds segments to the current path to make a quadratic curve.

Parameters:

xc - the X coordinate of the control point

yc - the Y coordinate of the control point

x1 - the X coordinate of the end point

y1 - the Y coordinate of the end point

bezierCurveTo

public void bezierCurveTo(double xc1,
                 double yc1,
                 double xc2,
                 double yc2,
                 double x1,
                 double y1)

Adds segments to the current path to make a cubic bezier curve.

Parameters:

xc1 - the X coordinate of first bezier control point.

yc1 - the Y coordinate of the first bezier control point.

xc2 - the X coordinate of the second bezier control point.

yc2 - the Y coordinate of the second bezier control point.

x1 - the X coordinate of the end point.

y1 - the Y coordinate of the end point.

arcTo

public void arcTo(double x1,
         double y1,
         double x2,
         double y2,
         double radius)

Adds segments to the current path to make an arc.

Parameters:

x1 - the X coordinate of the first point of the arc.

y1 - the Y coordinate of the first point of the arc.

x2 - the X coordinate of the second point of the arc.

y2 - the Y coordinate of the second point of the arc.

radius - the radius of the arc in the range {0.0-positive infinity}.

arc

public void arc(double centerX,
       double centerY,
       double radiusX,
       double radiusY,
       double startAngle,
       double length)

Adds path elements to the current path to make an arc that uses Euclidean degrees. This Euclidean orientation sweeps from East to North, then West, then South, then back to East.

Parameters:

centerX - the center x position of the arc.

centerY - the center y position of the arc.

radiusX - the x radius of the arc.

radiusY - the y radius of the arc.

startAngle - the starting angle of the arc in the range 0-360.0

length - the length of the baseline of the arc.

rect

public void rect(double x,
        double y,
        double w,
        double h)

Adds path elements to the current path to make a rectangle.

Parameters:

x - x position of the upper left corner of the rectangle.

y - y position of the upper left corner of the rectangle.

w - width of the rectangle.

h - height of the rectangle.

appendSVGPath

public void appendSVGPath(java.lang.String svgpath)

Appends an SVG Path string to the current path. If there is no current path the string must then start with either type of move command.

Parameters:

svgpath - the SVG Path string.

closePath

public void closePath()

Closes the path.

fill

public void fill()

Fills the path with the current fill paint.

stroke

public void stroke()

Strokes the path with the current stroke paint.

clip

public void clip()

Clips using the current path

isPointInPath

public boolean isPointInPath(double x,
                    double y)

Returns true if the the given x,y point is inside the path.

Parameters:

x - the X coordinate to use for the check.

y - the Y coordinate to use for the check.

Returns:

true if the point given is inside the path, false otherwise.

clearRect

public void clearRect(double x,
             double y,
             double w,
             double h)

Clears a portion of the canvas with a transparent color value.

Parameters:

x - X position of the upper left corner of the rectangle.

y - Y position of the upper left corner of the rectangle.

w - width of the rectangle.

h - height of the rectangle.

fillRect

public void fillRect(double x,
            double y,
            double w,
            double h)

Fills a rectangle using the current fill paint.

Parameters:

x - the X position of the upper left corner of the rectangle.

y - the Y position of the upper left corner of the rectangle.

w - the width of the rectangle.

h - the height of the rectangle.

strokeRect

public void strokeRect(double x,
              double y,
              double w,
              double h)

Strokes a rectangle using the current stroke paint.

Parameters:

x - the X position of the upper left corner of the rectangle.

y - the Y position of the upper left corner of the rectangle.

w - the width of the rectangle.

h - the height of the rectangle.

fillOval

public void fillOval(double x,
            double y,
            double w,
            double h)

Fills an oval using the current fill paint.

Parameters:

x - the X coordinate of the upper left bound of the oval.

y - the Y coordinate of the upper left bound of the oval.

w - the width at the center of the oval.

h - the height at the center of the oval.

strokeOval

public void strokeOval(double x,
              double y,
              double w,
              double h)

Strokes a rectangle using the current stroke paint.

Parameters:

x - the X coordinate of the upper left bound of the oval.

y - the Y coordinate of the upper left bound of the oval.

w - the width at the center of the oval.

h - the height at the center of the oval.

fillArc

public void fillArc(double x,
           double y,
           double w,
           double h,
           double startAngle,
           double arcExtent,
           ArcType closure)

Fills an arc using the current fill paint.

Parameters:

x - the X coordinate of the arc.

y - the Y coordinate of the arc.

w - the width of the arc.

h - the height of the arc.

startAngle - the starting angle of the arc in degrees.

arcExtent - the angular extent of the arc in degrees.

closure - closure type (Round, Chord, Open).

strokeArc

public void strokeArc(double x,
             double y,
             double w,
             double h,
             double startAngle,
             double arcExtent,
             ArcType closure)

Strokes an Arc using the current stroke paint.

Parameters:

x - the X coordinate of the arc.

y - the Y coordinate of the arc.

w - the width of the arc.

h - the height of the arc.

startAngle - the starting angle of the arc in degrees.

arcExtent - arcExtent the angular extent of the arc in degrees.

closure - closure type (Round, Chord, Open).

fillRoundRect

public void fillRoundRect(double x,
                 double y,
                 double w,
                 double h,
                 double arcWidth,
                 double arcHeight)

Fills a rounded rectangle using the current fill paint.

Parameters:

x - the X coordinate of the upper left bound of the oval.

y - the Y coordinate of the upper left bound of the oval.

w - the width at the center of the oval.

h - the height at the center of the oval.

arcWidth - the arc width of the rectangle corners.

arcHeight - the arc height of the rectangle corners.

strokeRoundRect

public void strokeRoundRect(double x,
                   double y,
                   double w,
                   double h,
                   double arcWidth,
                   double arcHeight)

Strokes a rounded rectangle using the current stroke paint.

Parameters:

x - the X coordinate of the upper left bound of the oval.

y - the Y coordinate of the upper left bound of the oval.

w - the width at the center of the oval.

h - the height at the center of the oval.

arcWidth - the arc width of the rectangle corners.

arcHeight - the arc height of the rectangle corners.

strokeLine

public void strokeLine(double x1,
              double y1,
              double x2,
              double y2)

Strokes a line using the current stroke paint.

Parameters:

x1 - the X coordinate of the starting point of the line.

y1 - the Y coordinate of the starting point of the line.

x2 - the X coordinate of the ending point of the line.

y2 - the Y coordinate of the ending point of the line.

fillPolygon

public void fillPolygon(double[] xPoints,
               double[] yPoints,
               int nPoints)

Fills a polygon with the given points using the currently set fill paint.

Parameters:

xPoints - array containing the x coordinates of the polygon's points.

yPoints - array containing the y coordinates of the polygon's points.

nPoints - the number of points that make the polygon.

strokePolygon

public void strokePolygon(double[] xPoints,
                 double[] yPoints,
                 int nPoints)

Strokes a polygon with the given points using the currently set stroke paint.

Parameters:

xPoints - array containing the x coordinates of the polygon's points.

yPoints - array containing the y coordinates of the polygon's points.

nPoints - the number of points that make the polygon.

strokePolyline

public void strokePolyline(double[] xPoints,
                  double[] yPoints,
                  int nPoints)

Draws a polyline with the given points using the currently set stroke paint attribute.

Parameters:

xPoints - array containing the x coordinates of the polyline's points.

yPoints - array containing the y coordinates of the polyline's points.

nPoints - the number of points that make the polyline.

drawImage

public void drawImage(Image img,
             double x,
             double y)

Draws an image at the given x, y position using the width and height of the given image.

Parameters:

img - the image to be drawn.

x - the X coordinate on the destination for the upper left of the image.

y - the Y coordinate on the destination for the upper left of the image.

drawImage

public void drawImage(Image img,
             double x,
             double y,
             double w,
             double h)

Draws an image into the given destination rectangle of the canvas. The Image is scaled to fit into the destination rectagnle.

Parameters:

img - the image to be drawn.

x - the X coordinate on the destination for the upper left of the image.

y - the Y coordinate on the destination for the upper left of the image.

w - the width of the destination rectangle.

h - the height of the destination rectangle.

drawImage

public void drawImage(Image img,
             double sx,
             double sy,
             double sw,
             double sh,
             double dx,
             double dy,
             double dw,
             double dh)

Draws the current source rectangle of the given image to the given destination rectangle of the Canvas.

Parameters:

img - the image to be drawn.

sx - the source rectangle's X coordinate position.

sy - the source rectangle's Y coordinate position.

sw - the source rectangle's width.

sh - the source rectangle's height.

dx - the destination rectangle's X coordinate position.

dy - the destination rectangle's Y coordinate position.

dw - the destination rectangle's width.

dh - the destination rectangle's height.

getPixelWriter

public PixelWriter getPixelWriter()

Returns a PixelWriter object that can be used to modify the pixels of the Canvas associated with this GraphicsContext. All coordinates in the PixelWriter methods on the returned object will be in device space since they refer directly to pixels.

Returns:

the PixelWriter for modifying the pixels of this Canvas

setEffect

public void setEffect(Effect e)

Sets the effect to be applied after the next draw call, or null to disable effects.

Parameters:

e - the effect to use, or null to disable effects

getEffect

public Effect getEffect(Effect e)

Gets a copy of the effect to be applied after the next draw call. A null return value means that no effect will be applied after future rendering calls.

Parameters:

e - an Effect object that may be used to store the copy of the current effect, if it is of a compatible type

Returns:

the current effect used for all rendering calls, or null if there is no current effect

applyEffect

public void applyEffect(Effect e)

Applies the given effect to the entire canvas.

Parameters:

e - the effect to apply onto the entire destination.