diff options
Diffstat (limited to 'libjava/classpath/gnu/java/awt/java2d/ScanlineConverter.java')
| -rw-r--r-- | libjava/classpath/gnu/java/awt/java2d/ScanlineConverter.java | 107 |
1 files changed, 75 insertions, 32 deletions
diff --git a/libjava/classpath/gnu/java/awt/java2d/ScanlineConverter.java b/libjava/classpath/gnu/java/awt/java2d/ScanlineConverter.java index 9f9d8921f59..2693a0b70c7 100644 --- a/libjava/classpath/gnu/java/awt/java2d/ScanlineConverter.java +++ b/libjava/classpath/gnu/java/awt/java2d/ScanlineConverter.java @@ -1,5 +1,5 @@ /* ScanlineConverter.java -- Rasterizes Shapes - Copyright (C) 2006 Free Software Foundation, Inc. + Copyright (C) 2006, 2007 Free Software Foundation, Inc. This file is part of GNU Classpath. @@ -40,6 +40,7 @@ package gnu.java.awt.java2d; import gnu.java.math.Fixed; +import java.awt.RenderingHints; import java.awt.Shape; import java.awt.geom.AffineTransform; import java.awt.geom.PathIterator; @@ -47,7 +48,7 @@ import java.awt.geom.PathIterator; /** * Rasterizes {@link Shape} objects on an AbstractGraphics2D. */ -final class ScanlineConverter +public final class ScanlineConverter { /** @@ -56,11 +57,16 @@ final class ScanlineConverter private static int FIXED_DIGITS = 6; /** - * The fixed value for the number 1. + * The fixed point constant for the number one. */ private static int ONE = Fixed.fixedValue(FIXED_DIGITS, 1); /** + * The number of significant bits for the Y resolution. + */ + private static int Y_RESOLUTION = 4; + + /** * The actual number of scanlines. */ private int numScanlines; @@ -109,6 +115,13 @@ final class ScanlineConverter private int minY; private int maxY; + private int minX; + private int maxX; + + /** + * Holds and manages information about the pixel coverage. + */ + private ScanlineCoverage scanlineCoverage; /** * Create a new ScanlineConverter. @@ -120,18 +133,23 @@ final class ScanlineConverter activeEdges = new ActiveEdges(); edgePool = new PolyEdge(); edgePoolLast = edgePool; + scanlineCoverage = new ScanlineCoverage(); } /** * Renders the specified shape using the specified clip and transform. * + * @param p the pixelizer that receives the coverage information * @param shape the shape to render * @param clip the clip * @param trans the transform */ - void renderShape(AbstractGraphics2D g, Shape shape, Shape clip, - AffineTransform trans, int res) + public void renderShape(Pixelizer p, Shape shape, Shape clip, + AffineTransform trans, int res, RenderingHints hints) { + // TODO: Do something useful with the rendering hints. Like, adjusting + // the resolution. + // Prepare resolution and upper bounds. clear(); setResolution(res); @@ -139,11 +157,12 @@ final class ScanlineConverter boolean haveClip = clip != null; // Add shapes. - PathIterator path = shape.getPathIterator(trans, resolution); + float flatness = Fixed.floatValue(FIXED_DIGITS, resolution / 2); + PathIterator path = shape.getPathIterator(trans, flatness); addShape(path, false); if (haveClip) { - path= clip.getPathIterator(trans, resolution); + path= clip.getPathIterator(trans, flatness); addShape(path, true); } @@ -157,11 +176,11 @@ final class ScanlineConverter } int y = upperBounds; - int lastIndex = scanlineIndex(y - resolution); int index; activeEdges.clear(); // The render loop... Scanline scanline = null; + int lastRealY = Fixed.intValue(FIXED_DIGITS, y); while (y <= maxY) { // First we put together our list of active edges. @@ -184,15 +203,16 @@ final class ScanlineConverter activeEdges.intersectSortAndPack(FIXED_DIGITS, y + halfStep); // Ok, now we can perform the actual scanlining. - boolean push = lastIndex != index; - doScanline(g, y, push, haveClip); + int realY = Fixed.intValue(FIXED_DIGITS, y + resolution); + boolean push = lastRealY != realY; + doScanline(p, y, push, haveClip); // Remove obsolete active edges. //activeEdges.remove(y + halfStep); - // Go on with the next line... y += resolution; - lastIndex = index; + lastRealY = realY; + } } @@ -212,17 +232,31 @@ final class ScanlineConverter sl.clear(); } + // Reset scanline coverage. + scanlineCoverage.clear(); + // Reset bounds. minY = Integer.MAX_VALUE; maxY = Integer.MIN_VALUE; + minX = Integer.MAX_VALUE; + maxX = Integer.MIN_VALUE; } /** * Performs the scanlining on the current set of active edges. + * + * @param p the pixelizer to receive the pixel coverage data + * @param y the Y coordinate + * @param push true when the scanline is ready to be pushed to the + * pixelizer + * @param haveClip true when there's a clip, false otherwise */ - private void doScanline(AbstractGraphics2D g, int y, boolean push, + private void doScanline(Pixelizer p, int y, boolean push, boolean haveClip) { + // First, rewind the scanline coverage. + scanlineCoverage.rewind(); + // We begin outside the clip and outside the shape. We only draw when // we are inside the clip AND inside the shape. boolean inClip = ! haveClip; @@ -238,22 +272,16 @@ final class ScanlineConverter int x0 = lastEdge.xIntersection; int x1 = edge.xIntersection; assert x0 <= x1; - if (push) - { - if (resolution == ONE) - { - // Non-AA rendering. - g.fillScanline(Fixed.intValue(FIXED_DIGITS, x0), - Fixed.intValue(FIXED_DIGITS, x1 - resolution), - Fixed.intValue(FIXED_DIGITS, y)); - } - else - { - // AA rendering. - // FIXME: Implement. - System.err.println("Implement AA rendering."); - } - } + + int pix0 = Fixed.intValue(FIXED_DIGITS, x0); + int pix1 = Fixed.intValue(FIXED_DIGITS, x1); + int frac0 = ONE - Fixed.trunc(FIXED_DIGITS, x0); + int frac1 = ONE - Fixed.trunc(FIXED_DIGITS, x1); + // Only keep the first 4 digits after the point. + frac0 = frac0 >> (FIXED_DIGITS - Y_RESOLUTION); + frac1 = frac1 >> (FIXED_DIGITS - Y_RESOLUTION); + scanlineCoverage.add(pix0, 1 * (1 << Y_RESOLUTION), frac0); + scanlineCoverage.add(pix1, -1 * (1 << Y_RESOLUTION), -frac1); } if (edge.isClip) inClip = ! inClip; @@ -262,7 +290,15 @@ final class ScanlineConverter lastEdge = edge; } - } + + // Push out the whole scanline to the pixelizer. + if (push && ! scanlineCoverage.isEmpty()) + { + p.renderScanline(Fixed.intValue(FIXED_DIGITS, y), scanlineCoverage); + scanlineCoverage.clear(); + } + } + /** * Sets the resolution. A value of 0 rasterizes the shape normally without @@ -272,9 +308,12 @@ final class ScanlineConverter */ private void setResolution(int res) { + int scanlinesPerPixel = 1 << res; int one = Fixed.fixedValue(FIXED_DIGITS, 1); - resolution = one / (1 << res); + resolution = one / (scanlinesPerPixel); halfStep = resolution / 2; + + scanlineCoverage.setMaxCoverage(scanlinesPerPixel << Y_RESOLUTION); } /** @@ -309,6 +348,8 @@ final class ScanlineConverter startY = lastY = Fixed.fixedValue(FIXED_DIGITS, coords[1]); minY = Math.min(startY, minY); maxY = Math.max(startY, maxY); + minX = Math.min(startX, minX); + maxX = Math.max(startX, maxX); break; case PathIterator.SEG_LINETO: int x = Fixed.fixedValue(FIXED_DIGITS, coords[0]); @@ -318,6 +359,8 @@ final class ScanlineConverter lastY = y; minY = Math.min(lastY, minY); maxY = Math.max(lastY, maxY); + minX = Math.min(lastX, minX); + maxX = Math.max(lastX, maxX); break; case PathIterator.SEG_CLOSE: edgePoolAdd(lastX, lastY, startX, startY, clip); @@ -371,7 +414,7 @@ final class ScanlineConverter { int val1 = Fixed.div(FIXED_DIGITS, y, resolution); int rounded = Fixed.round(FIXED_DIGITS, val1); - return Fixed.div(FIXED_DIGITS, rounded, resolution); + return Fixed.mul(FIXED_DIGITS, rounded, resolution); } /** |