6925760: Scaled graphics can cause overlapped LCD mode strings on Windows for pixel size > 48
Reviewed-by: igor, jgodinez
--- a/jdk/src/share/classes/sun/font/FileFontStrike.java Fri Jan 14 11:43:36 2011 -0800
+++ b/jdk/src/share/classes/sun/font/FileFontStrike.java Fri Jan 14 12:10:45 2011 -0800
@@ -566,10 +566,44 @@
if (glyphCode >= INVISIBLE_GLYPHS) {
return 0f;
}
+
+ /* Notes on the (getUserAdv == false) case.
+ *
+ * Setting getUserAdv == false is internal to this class.
+ * If there's no graphics transform we can let
+ * getGlyphAdvance take its course, and potentially caching in
+ * advances arrays, except for signalling that
+ * getUserAdv == false means there is no need to create an image.
+ * It is possible that code already calculated the user advance,
+ * and it is desirable to take advantage of that work.
+ * But, if there's a transform and we want device advance, we
+ * can't use any values cached in the advances arrays - unless
+ * first re-transform them into device space using 'desc.devTx'.
+ * invertDevTx is null if the graphics transform is identity,
+ * a translate, or non-invertible. The latter case should
+ * not ever occur in the getUserAdv == false path.
+ * In other words its either null, or the inversion of a
+ * simple uniform scale. If its null, we can populate and
+ * use the advance caches as normal.
+ *
+ * If we don't find a cached value, obtain the device advance and
+ * return it. This will get stashed on the image by the caller and any
+ * subsequent metrics calls will be able to use it as is the case
+ * whenever an image is what is initially requested.
+ *
+ * Don't query if there's a value cached on the image, since this
+ * getUserAdv==false code path is entered solely when none exists.
+ */
if (horizontalAdvances != null) {
advance = horizontalAdvances[glyphCode];
if (advance != Float.MAX_VALUE) {
- return advance;
+ if (!getUserAdv && invertDevTx != null) {
+ Point2D.Float metrics = new Point2D.Float(advance, 0f);
+ desc.devTx.deltaTransform(metrics, metrics);
+ return metrics.x;
+ } else {
+ return advance;
+ }
}
} else if (segmentedCache && segHorizontalAdvances != null) {
int segIndex = glyphCode >> SEGSHIFT;
@@ -577,11 +611,23 @@
if (subArray != null) {
advance = subArray[glyphCode % SEGSIZE];
if (advance != Float.MAX_VALUE) {
- return advance;
+ if (!getUserAdv && invertDevTx != null) {
+ Point2D.Float metrics = new Point2D.Float(advance, 0f);
+ desc.devTx.deltaTransform(metrics, metrics);
+ return metrics.x;
+ } else {
+ return advance;
+ }
}
}
}
+ if (!getUserAdv && invertDevTx != null) {
+ Point2D.Float metrics = new Point2D.Float();
+ fileFont.getGlyphMetrics(pScalerContext, glyphCode, metrics);
+ return metrics.x;
+ }
+
if (invertDevTx != null || !getUserAdv) {
/* If there is a device transform need x & y advance to
* transform back into user space.
@@ -725,7 +771,7 @@
return getGlyphMetrics(glyphCode, true);
}
- private Point2D.Float getGlyphMetrics(int glyphCode, boolean getUserAdv) {
+ private Point2D.Float getGlyphMetrics(int glyphCode, boolean getImage) {
Point2D.Float metrics = new Point2D.Float();
// !!! or do we force sgv user glyphs?
@@ -733,7 +779,7 @@
return metrics;
}
long glyphPtr;
- if (getImageWithAdvance && getUserAdv) {
+ if (getImageWithAdvance && getImage) {
/* A heuristic optimisation says that for most cases its
* worthwhile retrieving the image at the same time as the
* metrics. So here we get the image data even if its not
@@ -750,9 +796,9 @@
metrics.y = StrikeCache.unsafe.getFloat
(glyphPtr + StrikeCache.yAdvanceOffset);
/* advance is currently in device space, need to convert back
- * into user space, unless getUserAdv == false.
+ * into user space.
* This must not include the translation component. */
- if (invertDevTx != null && getUserAdv) {
+ if (invertDevTx != null) {
invertDevTx.deltaTransform(metrics, metrics);
}
} else {
@@ -781,9 +827,9 @@
if (value == null) {
fileFont.getGlyphMetrics(pScalerContext, glyphCode, metrics);
/* advance is currently in device space, need to convert back
- * into user space, unless getUserAdv == false.
+ * into user space.
*/
- if (invertDevTx != null && getUserAdv) {
+ if (invertDevTx != null) {
invertDevTx.deltaTransform(metrics, metrics);
}
value = new Point2D.Float(metrics.x, metrics.y);
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/FontClass/LCDScale.java Fri Jan 14 12:10:45 2011 -0800
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ *
+ * @bug 6925760
+ * @summary Scaled graphics causes overlapped LCD glyphs on Windows
+ */
+
+import java.awt.*;
+import java.awt.font.*;
+import java.awt.geom.*;
+
+public class LCDScale extends Component {
+
+ public static void main(String args[]) {
+ Frame f = new Frame("TL TEST");
+ LCDScale td = new LCDScale();
+ f.add("Center", td);
+ f.pack(); f.setVisible(true);
+ }
+
+
+ public LCDScale() {
+ super();
+ }
+
+ public Dimension getPreferredSize() {
+ return new Dimension(500,500);
+ }
+
+ public void paint(Graphics g) {
+ Graphics2D g2d = (Graphics2D)g;
+ g2d.setRenderingHint(
+ RenderingHints.KEY_TEXT_ANTIALIASING,
+ RenderingHints.VALUE_TEXT_ANTIALIAS_LCD_HRGB);
+
+ Font f = new Font("Dialog", Font.PLAIN, 40);
+ g.setFont(f);
+ FontRenderContext frc = g2d.getFontRenderContext();
+ GlyphVector gv = f.createGlyphVector(frc, "Help");
+ g2d.drawGlyphVector(gv, 10f, 50f);
+ Rectangle2D bds1 = gv.getLogicalBounds();
+
+ f = new Font("Arial", Font.PLAIN, 25);
+ g.setFont(f);
+ double s = 2.0;
+ AffineTransform tx = AffineTransform.getScaleInstance(s,s);
+ g2d.transform(tx);
+ frc = g2d.getFontRenderContext();
+ gv = f.createGlyphVector(frc, "Help");
+ g2d.drawGlyphVector(gv, 10f, 100f);
+ Rectangle2D bds2 = gv.getLogicalBounds();
+
+ System.out.println(bds1);
+ System.out.println(bds2);
+ if (bds2.getWidth()*s < bds1.getWidth()) {
+ throw new RuntimeException("Bounds too small");
+ }
+ }
+}
+
+