Package ca.cgjennings.graphics.composites

Class AbstractCompositeContext

java.lang.Object

ca.cgjennings.graphics.composites.AbstractCompositeContext

All Implemented Interfaces:

java.awt.CompositeContext

public abstract class AbstractCompositeContext
extends java.lang.Object
implements java.awt.CompositeContext

This abstract implementation of CompositeContext is designed to handle RGB/ARGB data. Subclasses must implement the abstract general case method, and may optionally override other methods to provide special case code for use when the VALUE_ALPHA_INTERPOLATION_SPEED hint is set and/or the source and destination both have 4 bands (ARGB). The context will transparently make use of multiple CPUs to increase compositing performance, so subclasses must ensure that their implementations of compose methods can be called concurrently from multiple threads.

Author:

Chris Jennings

Field Summary

Fields

Modifier and Type	Field	Description
protected float	alpha
protected java.awt.image.ColorModel	dstColorModel
protected boolean	fast
protected java.awt.RenderingHints	renderingHints
protected java.awt.image.ColorModel	srcColorModel

Constructor Summary

Constructors

Constructor	Description
AbstractCompositeContext(float alpha, java.awt.image.ColorModel srcColorModel, java.awt.image.ColorModel dstColorModel, java.awt.RenderingHints hints)

Method Summary

Modifier and Type	Method	Description
protected static int	clamp(int a)
protected abstract void	compose(int[] src, int[] dst, int sBands, int dBands, int aFactor)	Subclasses must override this to perform general case compositing.
void	compose(java.awt.image.Raster top, java.awt.image.Raster bottom, java.awt.image.WritableRaster dest)
protected void	compose44(int[] src, int[] dst, int aFactor)	This method can be overidden to provide fast special case code for images with 4 bands (A+RGB) in both source and destination.
protected void	composeF44(int[] src, int[] dst, int aFactor)	This method can be overidden to provide fast special case code for images with 4 bands (A+RGB) in both source and destination when the alpha interpolation rendering hint is set for speed.
protected void	composeFxx(int[] src, int[] dst, int sBands, int dBands, int aFactor)	This method can be overidden to provide fast special case code for images with variable bands in both source and destination when the alpha interpolation rendering hint is set for speed.
void	dispose()
protected static int	div(int a, int b)
protected static int	fmix(int aFactor, int b)
protected static int	mix(int aFactor, int b)
protected static int	mul(int a, int b)

Methods inherited from class java.lang.Object

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

Field Detail

alpha

protected final float alpha

srcColorModel

protected final java.awt.image.ColorModel srcColorModel

dstColorModel

protected final java.awt.image.ColorModel dstColorModel

renderingHints

protected final java.awt.RenderingHints renderingHints

fast

protected final boolean fast

Constructor Detail

AbstractCompositeContext

public AbstractCompositeContext(float alpha,
                                java.awt.image.ColorModel srcColorModel,
                                java.awt.image.ColorModel dstColorModel,
                                java.awt.RenderingHints hints)

Method Detail

compose

public void compose(java.awt.image.Raster top,
                    java.awt.image.Raster bottom,
                    java.awt.image.WritableRaster dest)

Specified by:

compose in interface java.awt.CompositeContext

compose

protected abstract void compose(int[] src,
                                int[] dst,
                                int sBands,
                                int dBands,
                                int aFactor)

Subclasses must override this to perform general case compositing.

Parameters:

src - the source data

dst - the destination data

sBands - the number of source bands

dBands - the number of destination bands

composeFxx

protected void composeFxx(int[] src,
                          int[] dst,
                          int sBands,
                          int dBands,
                          int aFactor)

This method can be overidden to provide fast special case code for images with variable bands in both source and destination when the alpha interpolation rendering hint is set for speed. The default implementation forwards to compose( src, dst, sBands, dBands, aFactor )

Parameters:

src - the source data to mix

dst - the destination to be mixed into

compose44

protected void compose44(int[] src,
                         int[] dst,
                         int aFactor)

This method can be overidden to provide fast special case code for images with 4 bands (A+RGB) in both source and destination. The default implementation forwards to composeF44( src, dst, aFactor )

Parameters:

src - the source data to mix

dst - the destination to be mixed into

composeF44

protected void composeF44(int[] src,
                          int[] dst,
                          int aFactor)

This method can be overidden to provide fast special case code for images with 4 bands (A+RGB) in both source and destination when the alpha interpolation rendering hint is set for speed. The default implementation forwards to compose( src, dst, 4, 4, aFactor )

Parameters:

src - the source data to mix

dst - the destination to be mixed into

dispose

public void dispose()

Specified by:

dispose in interface java.awt.CompositeContext

clamp

protected static int clamp(int a)

mul

protected static int mul(int a,
                         int b)

div

protected static int div(int a,
                         int b)

mix

protected static int mix(int aFactor,
                         int b)

fmix

protected static int fmix(int aFactor,
                          int b)