Canvas (PlayN Core 2.0.4 API)

java.lang.Object
- playn.core.Canvas

All Implemented Interfaces:

java.lang.AutoCloseable, Closeable
```
public abstract class Canvas
extends java.lang.Object
implements Closeable
```
A 2D drawing canvas. Rendering is performed by the CPU into a bitmap.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Canvas.Composite` Values that may be used with `setCompositeOperation(Composite)`.
`static interface`	`Canvas.Drawable` Facilitates drawing images and image regions to a canvas.
`static class`	`Canvas.LineCap` Values that may be used with `setLineCap(LineCap)`.
`static class`	`Canvas.LineJoin` Values that may be used with `setLineJoin(LineJoin)`.

Nested classes/interfaces inherited from interface react.Closeable
Closeable.Set, Closeable.Util

Field Summary

Fields
Modifier and Type Field and Description

float height
The height of this canvas.

Image image
The image that underlies this canvas.

float width
The width of this canvas.

Fields
Modifier and Type	Field and Description
`float`	`height` The height of this canvas.
`Image`	`image` The image that underlies this canvas.
`float`	`width` The width of this canvas.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`abstract Canvas`	`clear()` Clears the entire canvas to `rgba(0, 0, 0, 0)`.
`abstract Canvas`	`clearRect(float x, float y, float width, float height)` Clears the specified region to `rgba (0, 0, 0, 0)`.
`abstract Canvas`	`clip(Path clipPath)` Intersects the current clip with the specified path.
`abstract Canvas`	`clipRect(float x, float y, float width, float height)` Intersects the current clip with the supplied rectangle.
`void`	`close()` Informs the platform that this canvas, and its backing image will no longer be used.
`Gradient`	`createGradient(Gradient.Config config)` Creates a gradient fill pattern.
`Path`	`createPath()` Creates a path object.
`Canvas`	`draw(Canvas.Drawable image, float x, float y)` Draws `image` at the specified location `(x, y)`.
`Canvas`	`draw(Canvas.Drawable image, float x, float y, float w, float h)` Draws a scaled image at the specified location `(x, y)` size `(w x h)`.
`Canvas`	`draw(Canvas.Drawable image, float dx, float dy, float dw, float dh, float sx, float sy, float sw, float sh)` Draws a subregion of a image `(sw x sh) @ (sx, sy)` at the specified size `(dw x dh)` and location `(dx, dy)`.
`abstract Canvas`	`drawArc(float cx, float cy, float r, float startAngle, float arcAngle)` Draws an arc of a circle centered at cx, cy, with radius r.
`Canvas`	`drawCentered(Canvas.Drawable image, float x, float y)` Draws `image` centered at the specified location.
`abstract Canvas`	`drawLine(float x0, float y0, float x1, float y1)` Draws a line between the two specified points.
`abstract Canvas`	`drawPoint(float x, float y)` Draws a single point at the specified location.
`abstract Canvas`	`drawText(java.lang.String text, float x, float y)` Draws text at the specified location.
`abstract Canvas`	`fillCircle(float x, float y, float radius)` Fills a circle at the specified center and radius.
`abstract Canvas`	`fillPath(Path path)` Fills the specified path.
`abstract Canvas`	`fillRect(float x, float y, float width, float height)` Fills the specified rectangle.
`abstract Canvas`	`fillRoundRect(float x, float y, float width, float height, float radius)` Fills the specified rounded rectangle.
`abstract Canvas`	`fillText(TextLayout text, float x, float y)` Fills the text at the specified location.
`abstract Canvas`	`restore()` Restores the canvas's previous state.
`abstract Canvas`	`rotate(float radians)` Rotates the current transformation matrix by the specified angle in radians.
`abstract Canvas`	`save()` The save and restore methods preserve and restore the state of the canvas, but not specific paths or graphics.
`abstract Canvas`	`scale(float x, float y)` Scales the current transformation matrix by the specified amount.
`abstract Canvas`	`setAlpha(float alpha)` Set the global alpha value to be used for all painting.
`abstract Canvas`	`setCompositeOperation(Canvas.Composite composite)` Sets the Porter-Duff composite operation to be used for all painting.
`abstract Canvas`	`setFillColor(int color)` Sets the color to be used for fill operations.
`abstract Canvas`	`setFillGradient(Gradient gradient)` Sets the gradient to be used for fill operations.
`abstract Canvas`	`setFillPattern(Pattern pattern)` Sets the pattern to be used for fill operations.
`abstract Canvas`	`setLineCap(Canvas.LineCap cap)` Sets the line-cap mode for strokes.
`abstract Canvas`	`setLineJoin(Canvas.LineJoin join)` Sets the line-join mode for strokes.
`abstract Canvas`	`setMiterLimit(float miter)` Sets the miter limit for strokes.
`abstract Canvas`	`setStrokeColor(int color)` Sets the color for strokes.
`abstract Canvas`	`setStrokeWidth(float strokeWidth)` Sets the width for strokes, in pixels.
`abstract Image`	`snapshot()` Returns an immutable snapshot of the image that backs this canvas.
`abstract Canvas`	`strokeCircle(float x, float y, float radius)` Strokes a circle at the specified center and radius.
`abstract Canvas`	`strokePath(Path path)` Strokes the specified path.
`abstract Canvas`	`strokeRect(float x, float y, float width, float height)` Strokes the specified rectangle.
`abstract Canvas`	`strokeRoundRect(float x, float y, float width, float height, float radius)` Strokes the specified rounded rectangle.
`abstract Canvas`	`strokeText(TextLayout text, float x, float y)` Strokes the text at the specified location.
`Texture`	`toTexture()` Calls `toTexture(Texture.Config)` with the default texture config.
`Texture`	`toTexture(Texture.Config config)` A helper function for creating a texture from this canvas's image, and then disposing this canvas.
`abstract Canvas`	`transform(float m11, float m12, float m21, float m22, float dx, float dy)` Multiplies the current transformation matrix by the given matrix.
`abstract Canvas`	`translate(float x, float y)` Translates the current transformation matrix by the given amount.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - image
```
public final Image image
```
    The image that underlies this canvas.
  - width
```
public final float width
```
    The width of this canvas.
  - height
```
public final float height
```
    The height of this canvas.
- Method Detail
  - snapshot
```
public abstract Image snapshot()
```
    Returns an immutable snapshot of the image that backs this canvas. Subsequent changes to this canvas will not be reflected in the returned image. If you are going to render a canvas image into another canvas image a lot, using a snapshot can improve performance.
  - close
```
public void close()
```
    Informs the platform that this canvas, and its backing image will no longer be used. On some platforms this can free up memory earlier than if we waited for the canvas to be garbage collected.
    
    Specified by:
    
    close in interface java.lang.AutoCloseable
    
    Specified by:
    
    close in interface Closeable
  - clear
```
public abstract Canvas clear()
```
    Clears the entire canvas to rgba(0, 0, 0, 0).
  - clearRect
```
public abstract Canvas clearRect(float x,
                                 float y,
                                 float width,
                                 float height)
```
    Clears the specified region to rgba (0, 0, 0, 0).
  - clip
```
public abstract Canvas clip(Path clipPath)
```
    Intersects the current clip with the specified path.
  - clipRect
```
public abstract Canvas clipRect(float x,
                                float y,
                                float width,
                                float height)
```
    Intersects the current clip with the supplied rectangle.
  - createPath
```
public Path createPath()
```
    Creates a path object.
  - createGradient
```
public Gradient createGradient(Gradient.Config config)
```
    Creates a gradient fill pattern.
  - draw
```
public Canvas draw(Canvas.Drawable image,
                   float x,
                   float y)
```
    Draws image at the specified location (x, y).
  - drawCentered
```
public Canvas drawCentered(Canvas.Drawable image,
                           float x,
                           float y)
```
    Draws image centered at the specified location. Subtracts image.width/2 from x and image.height/2 from y.
  - draw
```
public Canvas draw(Canvas.Drawable image,
                   float x,
                   float y,
                   float w,
                   float h)
```
    Draws a scaled image at the specified location (x, y) size (w x h).
  - draw
```
public Canvas draw(Canvas.Drawable image,
                   float dx,
                   float dy,
                   float dw,
                   float dh,
                   float sx,
                   float sy,
                   float sw,
                   float sh)
```
    Draws a subregion of a image (sw x sh) @ (sx, sy) at the specified size (dw x dh) and location (dx, dy). TODO (jgw): Document whether out-of-bounds source coordinates clamp, repeat, or do nothing.
  - drawLine
```
public abstract Canvas drawLine(float x0,
                                float y0,
                                float x1,
                                float y1)
```
    Draws a line between the two specified points.
  - drawPoint
```
public abstract Canvas drawPoint(float x,
                                 float y)
```
    Draws a single point at the specified location.
  - drawArc
```
public abstract Canvas drawArc(float cx,
                               float cy,
                               float r,
                               float startAngle,
                               float arcAngle)
```
    Draws an arc of a circle centered at cx, cy, with radius r.
    The start and arc angles are specified in radians. Angles are interpreted such that 0 radians is at the 3 o'clock position. Positive values indicate a counter-clockwise rotation while negative values indicate a clockwise rotation.
  - drawText
```
public abstract Canvas drawText(java.lang.String text,
                                float x,
                                float y)
```
    Draws text at the specified location. The text will be drawn in the current fill color.
  - fillCircle
```
public abstract Canvas fillCircle(float x,
                                  float y,
                                  float radius)
```
    Fills a circle at the specified center and radius.
  - fillPath
```
public abstract Canvas fillPath(Path path)
```
    Fills the specified path.
  - fillRect
```
public abstract Canvas fillRect(float x,
                                float y,
                                float width,
                                float height)
```
    Fills the specified rectangle.
  - fillRoundRect
```
public abstract Canvas fillRoundRect(float x,
                                     float y,
                                     float width,
                                     float height,
                                     float radius)
```
    Fills the specified rounded rectangle.
    
    Parameters:
    
    x - the x coordinate of the upper left of the rounded rectangle.
    
    y - the y coordinate of the upper left of the rounded rectangle.
    
    width - the width of the rounded rectangle.
    
    height - the width of the rounded rectangle.
    
    radius - the radius of the circle to use for the corner.
  - fillText
```
public abstract Canvas fillText(TextLayout text,
                                float x,
                                float y)
```
    Fills the text at the specified location. The text will use the current fill color.
  - restore
```
public abstract Canvas restore()
```
    Restores the canvas's previous state.
    
    See Also:
    
    ()
  - rotate
```
public abstract Canvas rotate(float radians)
```
    Rotates the current transformation matrix by the specified angle in radians.
  - save
```
public abstract Canvas save()
```
    The save and restore methods preserve and restore the state of the canvas, but not specific paths or graphics. The following values are saved:
    - transformation matrix
    - clipping path
    - stroke color
    - stroke width
    - line cap
    - line join
    - miter limit
    - fill color or gradient
    - composite operation
  - scale
```
public abstract Canvas scale(float x,
                             float y)
```
    Scales the current transformation matrix by the specified amount.
  - setAlpha
```
public abstract Canvas setAlpha(float alpha)
```
    Set the global alpha value to be used for all painting.
    Values outside the range [0,1] will be clamped to the range [0,1].
    
    Parameters:
    
    alpha - alpha value in range [0,1] where 0 is transparent and 1 is opaque
  - setCompositeOperation
```
public abstract Canvas setCompositeOperation(Canvas.Composite composite)
```
    Sets the Porter-Duff composite operation to be used for all painting.
  - setFillColor
```
public abstract Canvas setFillColor(int color)
```
    Sets the color to be used for fill operations. This replaces any existing fill gradient or pattern.
  - setFillGradient
```
public abstract Canvas setFillGradient(Gradient gradient)
```
    Sets the gradient to be used for fill operations. This replaces any existing fill color or pattern.
  - setFillPattern
```
public abstract Canvas setFillPattern(Pattern pattern)
```
    Sets the pattern to be used for fill operations. This replaces any existing fill color or gradient.
  - setLineCap
```
public abstract Canvas setLineCap(Canvas.LineCap cap)
```
    Sets the line-cap mode for strokes.
  - setLineJoin
```
public abstract Canvas setLineJoin(Canvas.LineJoin join)
```
    Sets the line-join mode for strokes.
  - setMiterLimit
```
public abstract Canvas setMiterLimit(float miter)
```
    Sets the miter limit for strokes.
  - setStrokeColor
```
public abstract Canvas setStrokeColor(int color)
```
    Sets the color for strokes.
  - setStrokeWidth
```
public abstract Canvas setStrokeWidth(float strokeWidth)
```
    Sets the width for strokes, in pixels.
  - strokeCircle
```
public abstract Canvas strokeCircle(float x,
                                    float y,
                                    float radius)
```
    Strokes a circle at the specified center and radius.
  - strokePath
```
public abstract Canvas strokePath(Path path)
```
    Strokes the specified path.
  - strokeRect
```
public abstract Canvas strokeRect(float x,
                                  float y,
                                  float width,
                                  float height)
```
    Strokes the specified rectangle.
  - strokeRoundRect
```
public abstract Canvas strokeRoundRect(float x,
                                       float y,
                                       float width,
                                       float height,
                                       float radius)
```
    Strokes the specified rounded rectangle.
    
    Parameters:
    
    x - the x coordinate of the upper left of the rounded rectangle.
    
    y - the y coordinate of the upper left of the rounded rectangle.
    
    width - the width of the rounded rectangle.
    
    height - the width of the rounded rectangle.
    
    radius - the radius of the circle to use for the corner.
  - strokeText
```
public abstract Canvas strokeText(TextLayout text,
                                  float x,
                                  float y)
```
    Strokes the text at the specified location. The text will use the current stroke configuration (color, width, etc.).
  - toTexture
```
public Texture toTexture()
```
    Calls toTexture(Texture.Config) with the default texture config.
  - toTexture
```
public Texture toTexture(Texture.Config config)
```
    A helper function for creating a texture from this canvas's image, and then disposing this canvas. This is useful for situations where you create a canvas, draw something in it, turn it into a texture and then never use the canvas again.
  - transform
```
public abstract Canvas transform(float m11,
                                 float m12,
                                 float m21,
                                 float m22,
                                 float dx,
                                 float dy)
```
    Multiplies the current transformation matrix by the given matrix.
  - translate
```
public abstract Canvas translate(float x,
                                 float y)
```
    Translates the current transformation matrix by the given amount.

Class Canvas

Nested Class Summary

Nested classes/interfaces inherited from interface react.Closeable

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

image

width

height

Method Detail

snapshot

close

clear

clearRect

clip

clipRect

createPath

createGradient

draw

drawCentered

draw

draw

drawLine

drawPoint

drawArc

drawText

fillCircle

fillPath

fillRect

fillRoundRect

fillText

restore

rotate

save

scale

setAlpha

setCompositeOperation

setFillColor

setFillGradient

setFillPattern

setLineCap

setLineJoin

setMiterLimit

setStrokeColor

setStrokeWidth

strokeCircle

strokePath

strokeRect

strokeRoundRect

strokeText

toTexture

toTexture

transform

translate