TextBlob.getTightBounds

JetBrains · Dec 16, 2020 · c100dc6 · c100dc6
1 parent 470462a
commit c100dc6
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Showing 6 changed files with 128 additions and 10 deletions.
diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/Main.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/Main.java
@@ -356,11 +356,12 @@ private void loop() {
         scenes.put("Squares",          new SquaresScene());
         scenes.put("SVG",              new SVGScene());
         scenes.put("Swing",            new SwingScene());
-        scenes.put("Text Blob",        new TextBlobScene());
         scenes.put("Text Style",       new TextStyleScene());
+        scenes.put("TextBlob",         new TextBlobScene());
+        scenes.put("TextBlob Bounds",  new TextBlobBoundsScene());
         scenes.put("Wall of Text",     new WallOfTextScene());
         scenes.put("Watches",          new WatchesScene());
-        currentScene = "Paragraph";
+        currentScene = "TextBlob Bounds";
         t0 = System.nanoTime();
 
         while (!glfwWindowShouldClose(window)) {

diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/TextBlobBoundsScene.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/TextBlobBoundsScene.java
@@ -0,0 +1,59 @@
+package org.jetbrains.skija.examples.lwjgl;
+
+import java.util.*;
+import org.jetbrains.skija.*;
+import org.jetbrains.skija.shaper.*;
+
+public class TextBlobBoundsScene extends Scene {
+    private Paint fill = new Paint().setColor(0xFFCC3333);
+    private Paint stroke = new Paint().setColor(0x803333CC).setMode(PaintMode.STROKE).setStrokeWidth(1);
+    private Font inter18 = new Font(inter, 18);
+    private Font zapfino18 = new Font(FontMgr.getDefault().matchFamilyStyle("Zapfino", FontStyle.NORMAL), 18);
+
+    public TextBlobBoundsScene() {
+        _variants = new String[] { "Tight", "Loose" };
+    }
+
+    public void drawLine(Canvas canvas, String text, Font font) {
+        drawLine(canvas, text, font, Float.POSITIVE_INFINITY);
+    }
+
+    public void drawLine(Canvas canvas, String text, Font font, float width) {
+        drawLine(canvas, new String[] { text }, font, width);
+    }
+
+    public void drawLine(Canvas canvas, String[] texts, Font font) {
+        drawLine(canvas, texts, font, Float.POSITIVE_INFINITY);
+    }
+
+    public void drawLine(Canvas canvas, String[] texts, Font font, float width) {
+        canvas.save();
+        float bottom = 0;
+        for (var text: texts) {
+            try (var shaper = Shaper.makeShapeThenWrap();
+                 var blob = shaper.shape(text, font, width);)
+            {
+                var bounds = "Tight".equals(variantTitle()) ? blob.getTightBounds() : blob.getBounds();
+                canvas.drawCircle(0, 0, 3, stroke);
+                canvas.drawRect(bounds, stroke);
+                canvas.drawTextBlob(blob, 0, 0, font, fill);
+                canvas.translate(bounds.getRight() + 20, 0);
+                bottom = Math.max(bottom, bounds.getBottom());
+            }
+        }
+        canvas.restore();
+        canvas.translate(0, bottom + 20);
+    }
+
+    @Override
+    public void draw(Canvas canvas, int width, int height, float dpi, int xpos, int ypos) {
+        canvas.translate(20, 20);
+        drawLine(canvas, "onerun", inter18);
+        drawLine(canvas, "xyfx", inter18);
+        drawLine(canvas, new String[] { "one", "два", "three", "one два three" }, inter18);
+        drawLine(canvas, "multiple different lines", inter18, 50);
+        drawLine(canvas, new String[] { "ace", "الخطوط", "🧛", "ace الخطوط 🧛" }, inter18);
+        drawLine(canvas, "واحد اثنين ثلاثة", inter18);
+        drawLine(canvas, "fiz", zapfino18);
+    }
+}
diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/TextBlobScene.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/TextBlobScene.java
@@ -9,8 +9,7 @@ public class TextBlobScene extends Scene {
     private float gap = 40;
 
     public TextBlobScene() {
-        var face = Typeface.makeFromFile("fonts/InterHinted-Regular.ttf");
-        font = new Font(face, 24);
+        font = new Font(inter, 24);
     }
 
     @Override

diff --git a/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/WallOfTextScene.java b/examples/lwjgl/src/main/java/org/jetbrains/skija/examples/lwjgl/WallOfTextScene.java
@@ -14,6 +14,7 @@ public class WallOfTextScene extends Scene {
     private String[] words;
     private String text;
     private Paint fill = new Paint();
+    private Paint boundsStroke = new Paint().setColor(0x803333CC).setMode(PaintMode.STROKE).setStrokeWidth(1);
     private int[] colors;
     private FontCollection fc = null;
 
@@ -36,8 +37,9 @@ public WallOfTextScene() {
             "Paragraph with cache",
             "Paragraph no cache"
         };
-        _variantIdx = 8;
+        _variantIdx = 1;
         colors = new int[] {
+            0xFF000000,
             0xFFf94144,
             0xFFf3722c,
             0xFFf8961e,
@@ -99,16 +101,20 @@ TextBlob makeBlob(String text, Shaper shaper, float textWidth) {
     void drawByWords(Shaper shaper, Canvas canvas, float padding, float textWidth) {
         var x = padding;
         var y = padding;
+        var space = font.measureTextWidth(" ");
+        var lineHeight = font.getMetrics().getHeight();
         for (int i = 0; i < words.length; ++i) {
             try (var blob = makeBlob(words[i], shaper, Float.POSITIVE_INFINITY);) {
-                var bounds = blob.getBounds();
-                var wordWidth = bounds.getRight();
+                var bounds = blob.getTightBounds();
+                var wordWidth = bounds.getWidth();
                 if (x + wordWidth > textWidth) {
                     x = padding;
-                    y += bounds.getHeight();
+                    y += lineHeight;
                 }
+                fill.setColor(colors[i % colors.length]);
+                canvas.drawRect(bounds.translate(x, y), boundsStroke);
                 canvas.drawTextBlob(blob, x, y, font, fill);
-                x += wordWidth;
+                x += wordWidth + space;
             }
         }
     }

diff --git a/native/src/TextBlob.cc b/native/src/TextBlob.cc
@@ -99,6 +99,12 @@ extern "C" JNIEXPORT jlong JNICALL Java_org_jetbrains_skija_TextBlob__1nMakeFrom
 }
 
 // Must match SkTextBlobPriv.h
+//
+// Extended Textblob runs have more data after the Pos[] array:
+//
+//    -------------------------------------------------------------------------
+//    ... | RunRecord | Glyphs[] | Pos[] | TextSize | Clusters[] | Text[] | ...
+//    -------------------------------------------------------------------------
 class RunRecordClone {
 public:
     SkFont    fFont;
@@ -215,3 +221,30 @@ extern "C" JNIEXPORT jintArray JNICALL Java_org_jetbrains_skija_TextBlob__1nGetC
     }
     return javaIntArray(env, clusters);
 }
+
+extern "C" JNIEXPORT jobject JNICALL Java_org_jetbrains_skija_TextBlob__1nGetTightBounds
+  (JNIEnv* env, jclass jclass, jlong ptr) {
+    SkTextBlob* instance = reinterpret_cast<SkTextBlob*>(static_cast<uintptr_t>(ptr));
+    SkTextBlob::Iter iter(*instance);
+    SkTextBlob::Iter::Run run;
+    auto bounds = SkRect::MakeEmpty();
+    SkRect tmpBounds;
+    SkGlyphID glyph;
+    SkPoint pos;
+    bool first = false;
+    while (iter.next(&run)) {
+        // run.fGlyphIndices points directly to runRecord.glyphBuffer(), which comes directly after RunRecord itself
+        auto runRecord = reinterpret_cast<const RunRecordClone*>(run.fGlyphIndices) - 1;
+        if (runRecord->positioning() != 2) // kFull_Positioning
+            return nullptr;
+
+        runRecord->fFont.measureText(runRecord->glyphBuffer(), runRecord->fCount * sizeof(uint16_t), SkTextEncoding::kGlyphID, &tmpBounds, nullptr);
+        tmpBounds.offset(runRecord->posBuffer()[0], runRecord->posBuffer()[1]);
+        if (first) {
+            bounds.setLTRB(tmpBounds.fLeft, tmpBounds.fTop, tmpBounds.fRight, tmpBounds.fBottom);
+            first = false;
+        } else
+            bounds.join(tmpBounds);
+    }
+    return skija::Rect::fromSkRect(env, bounds);
+}
diff --git a/shared/src/main/java/org/jetbrains/skija/TextBlob.java b/shared/src/main/java/org/jetbrains/skija/TextBlob.java
@@ -204,6 +204,25 @@ public int[] getClusters() {
         }
     }
 
+    /**
+     * Only works on TextBlobs that come from TextBlobBuilderRunHandler/Shaper default handler.
+     * 
+     * @return  tight bounds around all the glyphs in the TextBlob
+     * @throws  IllegalArgumentException if TextBlob doesn’t have this information
+     */
+    @NotNull
+    public Rect getTightBounds() {
+        try {
+            Stats.onNativeCall();
+            Rect res = _nGetTightBounds(_ptr);
+            if (res == null)
+                throw new IllegalArgumentException();
+            return res;
+        } finally {
+            Reference.reachabilityFence(this);
+        }
+    }
+
     @ApiStatus.Internal
     public static class _FinalizerHolder {
         public static final long PTR = _nGetFinalizer();
@@ -220,5 +239,6 @@ public static class _FinalizerHolder {
     @ApiStatus.Internal public static native long _nMakeFromData(long dataPtr /*, SkDeserialProcs */);
     @ApiStatus.Internal public static native short[] _nGetGlyphs(long ptr);
     @ApiStatus.Internal public static native float[] _nGetPositions(long ptr);
-    @ApiStatus.Internal public static native int[]   _nGetClusters(long ptr);
+    @ApiStatus.Internal public static native int[] _nGetClusters(long ptr);
+    @ApiStatus.Internal public static native Rect _nGetTightBounds(long ptr);
 }