8057986: freetype code to get glyph outline does not handle initial control point properly
Reviewed-by: prr, dougfelt
Contributed-by: Behdad Esfahbod <behdad@google.com>, Igor Kopylov <ikopylov@google.com>
--- a/jdk/src/java.desktop/share/native/libfontmanager/freetypeScaler.c Fri Sep 12 18:37:58 2014 -0400
+++ b/jdk/src/java.desktop/share/native/libfontmanager/freetypeScaler.c Fri Sep 05 19:06:07 2014 -0700
@@ -1082,86 +1082,60 @@
return 1;
}
-static void addToGP(GPData* gpdata, FT_Outline*outline) {
- jbyte current_type=SEG_UNKNOWN;
- int i, j;
- jfloat x, y;
+static void addSeg(GPData *gp, jbyte type) {
+ gp->pointTypes[gp->numTypes++] = type;
+}
+
+static void addCoords(GPData *gp, FT_Vector *p) {
+ gp->pointCoords[gp->numCoords++] = F26Dot6ToFloat(p->x);
+ gp->pointCoords[gp->numCoords++] = -F26Dot6ToFloat(p->y);
+}
- j = 0;
- for(i=0; i<outline->n_points; i++) {
- x = F26Dot6ToFloat(outline->points[i].x);
- y = -F26Dot6ToFloat(outline->points[i].y);
+static int moveTo(FT_Vector *to, GPData *gp) {
+ if (gp->numCoords)
+ addSeg(gp, SEG_CLOSE);
+ addCoords(gp, to);
+ addSeg(gp, SEG_MOVETO);
+ return FT_Err_Ok;
+}
+
+static int lineTo(FT_Vector *to, GPData *gp) {
+ addCoords(gp, to);
+ addSeg(gp, SEG_LINETO);
+ return FT_Err_Ok;
+}
- if (FT_CURVE_TAG(outline->tags[i]) == FT_CURVE_TAG_ON) {
- /* If bit 0 is unset, the point is "off" the curve,
- i.e., a Bezier control point, while it is "on" when set. */
- if (current_type == SEG_UNKNOWN) { /* special case:
- very first point */
- /* add segment */
- gpdata->pointTypes[gpdata->numTypes++] = SEG_MOVETO;
- current_type = SEG_LINETO;
- } else {
- gpdata->pointTypes[gpdata->numTypes++] = current_type;
- current_type = SEG_LINETO;
- }
- } else {
- if (current_type == SEG_UNKNOWN) { /* special case:
- very first point */
- if (FT_CURVE_TAG(outline->tags[i+1]) == FT_CURVE_TAG_ON) {
- /* just skip first point. Adhoc heuristic? */
- continue;
- } else {
- x = (x + F26Dot6ToFloat(outline->points[i+1].x))/2;
- y = (y - F26Dot6ToFloat(outline->points[i+1].y))/2;
- gpdata->pointTypes[gpdata->numTypes++] = SEG_MOVETO;
- current_type = SEG_LINETO;
- }
- } else if (FT_CURVE_TAG(outline->tags[i]) == FT_CURVE_TAG_CUBIC) {
- /* Bit 1 is meaningful for 'off' points only.
- If set, it indicates a third-order Bezier arc control
- point; and a second-order control point if unset. */
- current_type = SEG_CUBICTO;
- } else {
- /* two successive conic "off" points forces the rasterizer
- to create (during the scan-line conversion process
- exclusively) a virtual "on" point amidst them, at their
- exact middle. This greatly facilitates the definition of
- successive conic Bezier arcs. Moreover, it is the way
- outlines are described in the TrueType specification. */
- if (current_type == SEG_QUADTO) {
- gpdata->pointCoords[gpdata->numCoords++] =
- F26Dot6ToFloat(outline->points[i].x +
- outline->points[i-1].x)/2;
- gpdata->pointCoords[gpdata->numCoords++] =
- - F26Dot6ToFloat(outline->points[i].y +
- outline->points[i-1].y)/2;
- gpdata->pointTypes[gpdata->numTypes++] = SEG_QUADTO;
- }
- current_type = SEG_QUADTO;
- }
- }
- gpdata->pointCoords[gpdata->numCoords++] = x;
- gpdata->pointCoords[gpdata->numCoords++] = y;
- if (outline->contours[j] == i) { //end of contour
- int start = j > 0 ? outline->contours[j-1]+1 : 0;
- gpdata->pointTypes[gpdata->numTypes++] = current_type;
- if (current_type == SEG_QUADTO &&
- FT_CURVE_TAG(outline->tags[start]) != FT_CURVE_TAG_ON) {
- gpdata->pointCoords[gpdata->numCoords++] =
- (F26Dot6ToFloat(outline->points[start].x) + x)/2;
- gpdata->pointCoords[gpdata->numCoords++] =
- (-F26Dot6ToFloat(outline->points[start].y) + y)/2;
- } else {
- gpdata->pointCoords[gpdata->numCoords++] =
- F26Dot6ToFloat(outline->points[start].x);
- gpdata->pointCoords[gpdata->numCoords++] =
- -F26Dot6ToFloat(outline->points[start].y);
- }
- gpdata->pointTypes[gpdata->numTypes++] = SEG_CLOSE;
- current_type = SEG_UNKNOWN;
- j++;
- }
- }
+static int conicTo(FT_Vector *control, FT_Vector *to, GPData *gp) {
+ addCoords(gp, control);
+ addCoords(gp, to);
+ addSeg(gp, SEG_QUADTO);
+ return FT_Err_Ok;
+}
+
+static int cubicTo(FT_Vector *control1,
+ FT_Vector *control2,
+ FT_Vector *to,
+ GPData *gp) {
+ addCoords(gp, control1);
+ addCoords(gp, control2);
+ addCoords(gp, to);
+ addSeg(gp, SEG_CUBICTO);
+ return FT_Err_Ok;
+}
+
+static void addToGP(GPData* gpdata, FT_Outline*outline) {
+ static const FT_Outline_Funcs outline_funcs = {
+ (FT_Outline_MoveToFunc) moveTo,
+ (FT_Outline_LineToFunc) lineTo,
+ (FT_Outline_ConicToFunc) conicTo,
+ (FT_Outline_CubicToFunc) cubicTo,
+ 0, /* shift */
+ 0, /* delta */
+ };
+
+ FT_Outline_Decompose(outline, &outline_funcs, gpdata);
+ if (gpdata->numCoords)
+ addSeg(gpdata, SEG_CLOSE);
/* If set to 1, the outline will be filled using the even-odd fill rule */
if (outline->flags & FT_OUTLINE_EVEN_ODD_FILL) {
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/font/GlyphVector/GlyphVectorOutline.java Fri Sep 05 19:06:07 2014 -0700
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2014 Google Inc. 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.
+ */
+
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics2D;
+import java.awt.Image;
+import java.awt.font.FontRenderContext;
+import java.awt.font.GlyphVector;
+import java.awt.font.LineBreakMeasurer;
+import java.awt.font.TextAttribute;
+import java.awt.font.TextLayout;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.text.AttributedString;
+
+import javax.imageio.ImageIO;
+
+/**
+ * Manual test for:
+ * JDK-8057986: freetype code to get glyph outline does not handle initial control point properly
+ *
+ * Manual repro recipe:
+ * (cd test/java/awt/font/GlyphVector/ && javac GlyphVectorOutline.java && wget -q -O/tmp/msgothic.ttc https://browserlinux-jp.googlecode.com/files/msgothic.ttc && java GlyphVectorOutline /tmp/msgothic.ttc /tmp/katakana.png)
+ *
+ * Then examine the two rendered Japanese characters in the png file.
+ *
+ * Renders text to a PNG by
+ * 1. using the native Graphics2D#drawGlyphVector implementation
+ * 2. filling in the result of GlyphVector#getOutline
+ *
+ * Should be the same but is different for some CJK characters
+ * (e.g. Katakana character \u30AF).
+ *
+ * @author ikopylov@google.com (Igor Kopylov)
+ */
+public class GlyphVectorOutline {
+ public static void main(String[] args) throws Exception {
+ if (args.length != 2) {
+ throw new Error("Usage: java GlyphVectorOutline fontfile outputfile");
+ }
+ writeImage(new File(args[0]),
+ new File(args[1]),
+ "\u30AF");
+ }
+
+ public static void writeImage(File fontFile, File outputFile, String value) throws Exception {
+ BufferedImage image = new BufferedImage(200, 200, BufferedImage.TYPE_INT_RGB);
+ Graphics2D g = image.createGraphics();
+ g.setColor(Color.WHITE);
+ g.fillRect(0, 0, image.getWidth(), image.getHeight());
+ g.setColor(Color.BLACK);
+
+ Font font = Font.createFont(Font.TRUETYPE_FONT, fontFile);
+ font = font.deriveFont(Font.PLAIN, 72f);
+ FontRenderContext frc = new FontRenderContext(null, false, false);
+ GlyphVector gv = font.createGlyphVector(frc, value);
+ g.drawGlyphVector(gv, 10, 80);
+ g.fill(gv.getOutline(10, 180));
+ ImageIO.write(image, "png", outputFile);
+ }
+
+ private static void drawString(Graphics2D g, Font font, String value, float x, float y) {
+ AttributedString str = new AttributedString(value);
+ str.addAttribute(TextAttribute.FOREGROUND, Color.BLACK);
+ str.addAttribute(TextAttribute.FONT, font);
+ FontRenderContext frc = new FontRenderContext(null, true, true);
+ TextLayout layout = new LineBreakMeasurer(str.getIterator(), frc).nextLayout(Integer.MAX_VALUE);
+ layout.draw(g, x, y);
+ }
+}