Fixed infinite loop in Trivial iterators (closes #63)

JetBrains · Nov 27, 2020 · 57ec197 · 57ec197
1 parent c02cf05
commit 57ec197
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Showing 8 changed files with 33 additions and 25 deletions.
diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/FontScene.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/FontScene.java
@@ -47,10 +47,13 @@ public FontScene() {
 
     public float _drawLine(Canvas canvas, String text, Font font) {
         var blob = Shaper.make().shape(text, font);
-        var bounds = blob.getBounds();
-        canvas.drawTextBlob(blob, 0, 0, font, _paint);
-        canvas.translate(0, bounds.getHeight());
-        return bounds.getHeight();
+        if (blob != null) {
+            var bounds = blob.getBounds();
+            canvas.drawTextBlob(blob, 0, 0, font, _paint);
+            canvas.translate(0, bounds.getHeight());
+            return bounds.getHeight();
+        }
+        return 0;
     }
 
     @Override
@@ -77,7 +80,7 @@ public void draw(Canvas canvas, int windowWidth, int windowHeight, float dpi, in
     }
 
     public void drawInter(Canvas canvas) {
-
+        _drawLine(canvas, "", _defaultFont);
         _drawLine(canvas, "Default", _defaultFont);
         _drawLine(canvas, "Inter size=18", _inter18);
         _drawLine(canvas, "Inter size=13 scaleX=1", _inter13_1_0);

diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/ParagraphScene.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/ParagraphScene.java
@@ -196,7 +196,7 @@ public void drawMetrics(Canvas canvas, float dx, float dy) {
             pb.addText(" is true\n");
 
             pb.pushStyle(largeTs);
-            pb.addText("The previous ");
+            pb.addText("The previous       ");
             pb.popStyle();
             pb.addText("sentence");
             pb.pushStyle(largeTs);

diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/RunIteratorScene.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/RunIteratorScene.java
@@ -119,16 +119,18 @@ public void draw(Canvas canvas, int width, int height, float dpi, int xpos, int
     private void drawBlob(Canvas canvas, DebugTextBlobHandler handler, String comment) {
         canvas.drawString(comment, 0, -inter11Metrics.getAscent(), inter11, textFill);
         canvas.translate(0, inter11Metrics.getHeight());
-
-        try (var blob = handler._builder.build()) {
-            canvas.drawTextBlob(blob, 0, 0, lato36, textFill);
-
-            for (var triple: handler._infos) {
-                var runBounds = triple.getThird();
-                canvas.drawRect(runBounds, boundsStroke);
+        var blob = handler._builder.build();
+        if (blob != null) {
+            try (blob) {
+                canvas.drawTextBlob(blob, 0, 0, lato36, textFill);
+
+                for (var triple: handler._infos) {
+                    var runBounds = triple.getThird();
+                    canvas.drawRect(runBounds, boundsStroke);
+                }
+
+                canvas.translate(0, blob.getBounds().getBottom() + 20);
             }
-
-            canvas.translate(0, blob.getBounds().getBottom() + 20);
         }
     }
 }

diff --git a/shared/src/main/java/org/jetbrains/skija/shaper/TextBlobBuilderRunHandler.java b/shared/src/main/java/org/jetbrains/skija/shaper/TextBlobBuilderRunHandler.java
@@ -61,12 +61,11 @@ public void commitLine() {
         throw new UnsupportedOperationException("commitLine");
     }
 
+    @Nullable
     public TextBlob makeBlob() {
         Stats.onNativeCall();
         long ptr = _nMakeBlob(_ptr);
-        if (0 == ptr)
-            throw new RuntimeException("Failed to shape: " + _text);
-        return new TextBlob(ptr);
+        return 0 == ptr ? null : new TextBlob(ptr);
     }
 
     @ApiStatus.Internal

diff --git a/shared/src/main/java/org/jetbrains/skija/shaper/TrivialBidiRunIterator.java b/shared/src/main/java/org/jetbrains/skija/shaper/TrivialBidiRunIterator.java
@@ -7,11 +7,12 @@
 public class TrivialBidiRunIterator implements Iterator<BidiRun> {
     @ApiStatus.Internal public final int _length;
     @ApiStatus.Internal public final int _level;
-    @ApiStatus.Internal public boolean _atEnd = false;
+    @ApiStatus.Internal public boolean _atEnd;
 
     public TrivialBidiRunIterator(String text, int level) {
         _length = text.length();
-        _level = level;
+        _level  = level;
+        _atEnd  = _length == 0;
     }
 
     @Override

diff --git a/shared/src/main/java/org/jetbrains/skija/shaper/TrivialFontRunIterator.java b/shared/src/main/java/org/jetbrains/skija/shaper/TrivialFontRunIterator.java
@@ -7,11 +7,12 @@
 public class TrivialFontRunIterator implements Iterator<FontRun> {
     @ApiStatus.Internal public final int     _length;
     @ApiStatus.Internal public final Font    _font;
-    @ApiStatus.Internal public       boolean _atEnd = false;
+    @ApiStatus.Internal public       boolean _atEnd;
 
     public TrivialFontRunIterator(String text, Font font) {
         _length = text.length();
-        _font = font;
+        _font   = font;
+        _atEnd  = _length == 0;
     }
 
     @Override

diff --git a/shared/src/main/java/org/jetbrains/skija/shaper/TrivialLanguageRunIterator.java b/shared/src/main/java/org/jetbrains/skija/shaper/TrivialLanguageRunIterator.java
@@ -7,11 +7,12 @@
 public class TrivialLanguageRunIterator implements Iterator<LanguageRun> {
     @ApiStatus.Internal public final int     _length;
     @ApiStatus.Internal public final String  _language;
-    @ApiStatus.Internal public       boolean _atEnd = false;
+    @ApiStatus.Internal public       boolean _atEnd;
 
     public TrivialLanguageRunIterator(String text, String language) {
-        _length = text.length();
+        _length   = text.length();
         _language = language;
+        _atEnd    = _length == 0;
     }
 
     @Override

diff --git a/shared/src/main/java/org/jetbrains/skija/shaper/TrivialScriptRunIterator.java b/shared/src/main/java/org/jetbrains/skija/shaper/TrivialScriptRunIterator.java
@@ -7,11 +7,12 @@
 public class TrivialScriptRunIterator implements Iterator<ScriptRun> {
     @ApiStatus.Internal public final int     _length;
     @ApiStatus.Internal public final String  _script;
-    @ApiStatus.Internal public       boolean _atEnd = false;
+    @ApiStatus.Internal public       boolean _atEnd;
 
     public TrivialScriptRunIterator(String text, String script) {
         _length = text.length();
         _script = script;
+        _atEnd  = _length == 0;
     }
 
     @Override