ch.randelshofer.awt.graphics
Class OpaqueAntialiasingPipe

java.lang.Object
  java.awt.Graphics
      java.awt.Graphics2D
          ch.randelshofer.awt.graphics.Pipe
              ch.randelshofer.awt.graphics.AbstractPipe
                  ch.randelshofer.awt.graphics.OpaquePipe
                      ch.randelshofer.awt.graphics.OpaqueAntialiasingPipe

public class OpaqueAntialiasingPipe
extends OpaquePipe

A rendering pipe to render graphics primitives with antialiasing with opaque colors. This Graphics2D object only works with a BufferedImage which has the following characteristics:

• It must use a SinglePixelPackedSampleModel using a data buffer of type int and with the RGB bit masks: 0xff0000, 0xff00, 0xff.
• The underlying writable raster must use a DataBufferInt with a single band of data.

Usage:

 // Create a raster and a buffered image using the supported characteristics.
 WritableRaster ras = Raster.createWritableRaster(
      new SinglePixelPackedSampleModel(DataBuffer.TYPE_INT, gw, gh,
      new int[] {0xff0000, 0xff00, 0xff}),
      new Point(0,0)
      );

 BufferedImage bufferedImage = new BufferedImage(
      new DirectColorModel(24, 0xff0000, 0xff00, 0xff),
      ras, false, new Hashtable());

 // Create the graphics object
 OpaqueAntialiasingPipe g = new OpaqueAntialiasingPipe(bufferedImage);

 // Perform the grapics operations
 g.drawLine(0,0,100,100);
 

XXX - This is a purely experimental implementation. Eventually all code here will be replaced by algorithms taken from the anti-grain project.

Version:

1.0.1 2007-10-06 Fill method missed moveTo segments.
1.0 2007-08-27 Derived from TranslucentAntialiasingPipe.

Author:

Werner Randelshofer

Field Summary

protected int	alpha Precomputed values to speed up alpha compositing.
protected int	blueBits
protected int	greenBits
protected int	oneMinusAlpha
protected int	premultipliedB
protected int	premultipliedG
protected int	premultipliedR
protected int	previousIn
protected int	previousOut
protected int	redBits

Fields inherited from class ch.randelshofer.awt.graphics.OpaquePipe

color, colorBar, edges

Fields inherited from class ch.randelshofer.awt.graphics.AbstractPipe

background, flatness, mis, pixels, previousClip, previousTransform, ras, tx, ty, u1, u2

Fields inherited from class ch.randelshofer.awt.graphics.Pipe

cx1, cx2, cy1, cy2, gh, gw

Constructor Summary

OpaqueAntialiasingPipe(java.awt.image.BufferedImage image)
Creates a new instance.

Method Summary

protected void	blend(int xy, int intensity) Blends an individual pixel at the specified coordinate with the specified alpha transparency.
void	draw(java.awt.Shape s)
void	drawLine(int x1, int y1, int x2, int y2)
void	fill(java.awt.Shape s)
void	fillPolygon(int[] xPoints, int[] yPoints, int nPoints)
protected void	plot(int xy) Plots a single pixel.
protected void	plotH(int scan, ch.randelshofer.awt.graphics.Edge active) Fills a scan line between pairs of edges in the active edge list.
protected void	plotHClipped(int scan, ch.randelshofer.awt.graphics.Edge active) Fills a scan line between pairs of edges in the active edge list.
protected void	plotLine(int x1, int y1, int x2, int y2) Wu antialised line algorithm taken from: http://www.codeproject.com/gdi/antialias.asp#dwuln
protected void	plotVClipped(int scan, ch.randelshofer.awt.graphics.Edge active)
protected void	scanFillHorizontal(int[] x, int[] y, int cnt, int miny, int maxy) ScanFill algorithm for shapes which are wider than tall.
protected void	scanFillVertical(int[] x, int[] y, int cnt, int minx, int maxx) ScanFill algorithm for shapes which are taller than wide.
void	setColor(java.awt.Color c)

Methods inherited from class ch.randelshofer.awt.graphics.OpaquePipe

buildActiveList, buildEdgeListHorizontal, buildEdgeListVertical, deleteAfter, drawDigital, drawGlyphVector, drawOval, drawPolygon, drawPolyline, drawRect, drawWithSubpixelAccuracy, fillOval, fillRect, getColor, insertEdge, makeEdgeRecHorizontal, makeEdgeRecVertical, prepareEdgeList, resortActiveList, updateActiveList, xNext, yNext

Methods inherited from class ch.randelshofer.awt.graphics.AbstractPipe

arrayfill, clearRect, clipRect, clipTest, clipTest, flush, getBackground, setBackground, setClip, setClip, setComposite, setTransform, transform, translate, translate

Methods inherited from class ch.randelshofer.awt.graphics.Pipe

addRenderingHints, clip, copyArea, create, dispose, drawArc, drawImage, drawImage, drawImage, drawImage, drawImage, drawImage, drawImage, drawImage, drawRenderableImage, drawRenderedImage, drawRoundRect, drawString, drawString, drawString, drawString, fillArc, fillRoundRect, getClip, getClipBounds, getComposite, getDeviceConfiguration, getFont, getFontMetrics, getFontRenderContext, getPaint, getRenderingHint, getRenderingHints, getStroke, getTransform, hit, rotate, rotate, scale, setFont, setPaint, setPaintMode, setRenderingHint, setRenderingHints, setStroke, setXORMode, shear, toString

Methods inherited from class java.awt.Graphics2D

draw3DRect, fill3DRect

Methods inherited from class java.awt.Graphics

create, drawBytes, drawChars, drawPolygon, fillPolygon, finalize, getClipBounds, getClipRect, getFontMetrics, hitClip

Methods inherited from class java.lang.Object

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

Field Detail

alpha

protected int alpha

Precomputed values to speed up alpha compositing.

oneMinusAlpha

protected int oneMinusAlpha

premultipliedR

protected int premultipliedR

premultipliedG

protected int premultipliedG

premultipliedB

protected int premultipliedB

previousIn

protected int previousIn

previousOut

protected int previousOut

redBits

protected int redBits

greenBits

protected int greenBits

blueBits

protected int blueBits

Constructor Detail

OpaqueAntialiasingPipe

public OpaqueAntialiasingPipe(java.awt.image.BufferedImage image)

Creates a new instance.

Method Detail

drawLine

public void drawLine(int x1,
                     int y1,
                     int x2,
                     int y2)

Overrides:

drawLine in class OpaquePipe

plotLine

protected void plotLine(int x1,
                        int y1,
                        int x2,
                        int y2)

Wu antialised line algorithm taken from: http://www.codeproject.com/gdi/antialias.asp#dwuln

Parameters:

x1 - start point of line

y1 - start point of line

x2 - end point of line

y2 - end point of line

plot

protected void plot(int xy)

Plots a single pixel.

blend

protected void blend(int xy,
                     int intensity)

Blends an individual pixel at the specified coordinate with the specified alpha transparency. This operation does no clipping.

Parameters:

xy - coordinate of the pixel

intensity - 0=fully transparent, 255=fully opaque

setColor

public void setColor(java.awt.Color c)

Overrides:

setColor in class OpaquePipe

draw

public void draw(java.awt.Shape s)

Overrides:

draw in class OpaquePipe

fillPolygon

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

Overrides:

fillPolygon in class OpaquePipe

fill

public void fill(java.awt.Shape s)

Overrides:

fill in class OpaquePipe

scanFillHorizontal

protected void scanFillHorizontal(int[] x,
                                  int[] y,
                                  int cnt,
                                  int miny,
                                  int maxy)

ScanFill algorithm for shapes which are wider than tall.

Overrides:

scanFillHorizontal in class OpaquePipe

Parameters:

miny - Must be = smallest y and >= cy1.

maxy - Must be = biggest y and <= cy2.

scanFillVertical

protected void scanFillVertical(int[] x,
                                int[] y,
                                int cnt,
                                int minx,
                                int maxx)

ScanFill algorithm for shapes which are taller than wide.

Overrides:

scanFillVertical in class OpaquePipe

Parameters:

minx - Must be = smallest x and >= cx1.

maxx - Must be = biggest x and <= cx2.

plotHClipped

protected void plotHClipped(int scan,
                            ch.randelshofer.awt.graphics.Edge active)

Fills a scan line between pairs of edges in the active edge list. Uses a brute force algorithm to perform antialiasing.

plotH

protected void plotH(int scan,
                     ch.randelshofer.awt.graphics.Edge active)

Fills a scan line between pairs of edges in the active edge list. Uses a brute force algorithm to perform antialiasing.

plotVClipped

protected void plotVClipped(int scan,
                            ch.randelshofer.awt.graphics.Edge active)