4 files changed, 89 insertions, 6 deletions

diff --git a/src/core/SkBBoxHierarchyRecord.cpp b/src/core/SkBBoxHierarchyRecord.cpp
index f0382e6470..d6fbd21239 100644
--- a/src/core/SkBBoxHierarchyRecord.cpp
+++ b/src/core/SkBBoxHierarchyRecord.cpp
@@ -35,8 +35,29 @@ void SkBBoxHierarchyRecord::willSave(SaveFlags flags) {
 SkCanvas::SaveLayerStrategy SkBBoxHierarchyRecord::willSaveLayer(const SkRect* bounds,
                                                                  const SkPaint* paint,
                                                                  SaveFlags flags) {
+    // For now, assume all filters affect transparent black.
+    // FIXME: This could be made less conservative as an optimization.
+    bool paintAffectsTransparentBlack = NULL != paint &&
+        ((NULL != paint->getImageFilter()) ||
+         (NULL != paint->getColorFilter()));
+    SkRect drawBounds;
+    if (paintAffectsTransparentBlack) {
+        if (bounds) {
+            drawBounds = *bounds;
+            this->getTotalMatrix().mapRect(&drawBounds);
+        } else {
+            SkIRect deviceBounds;
+            this->getClipDeviceBounds(&deviceBounds);
+            drawBounds.set(deviceBounds);
+        }
+    }
     fStateTree->appendSaveLayer(this->writeStream().bytesWritten());
-    return this->INHERITED::willSaveLayer(bounds, paint, flags);
+    SkCanvas::SaveLayerStrategy strategy = this->INHERITED::willSaveLayer(bounds, paint, flags);
+    if (paintAffectsTransparentBlack) {
+        this->handleBBox(drawBounds);
+        this->addNoOp();
+    }
+    return strategy;
 }
 
 void SkBBoxHierarchyRecord::willRestore() {
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index f6da2f2793..4a5aff2d72 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -293,15 +293,14 @@ static bool match(SkWriter32* writer, uint32_t offset,
     int numMatched;
     for (numMatched = 0; numMatched < numCommands && curOffset < writer->bytesWritten(); ++numMatched) {
         DrawType op = peek_op_and_size(writer, curOffset, &curSize);
-        while (NOOP == op && curOffset < writer->bytesWritten()) {
+        while (NOOP == op) {
             curOffset += curSize;
+            if (curOffset >= writer->bytesWritten()) {
+                return false;
+            }
             op = peek_op_and_size(writer, curOffset, &curSize);
         }
 
-        if (curOffset >= writer->bytesWritten()) {
-            return false; // ran out of byte stream
-        }
-
         if (kDRAW_BITMAP_FLAVOR == pattern[numMatched]) {
             if (DRAW_BITMAP != op && DRAW_BITMAP_MATRIX != op &&
                 DRAW_BITMAP_NINE != op && DRAW_BITMAP_RECT_TO_RECT != op) {
@@ -1649,6 +1648,11 @@ void SkPictureRecord::addPoints(const SkPoint pts[], int count) {
 #endif
 }
 
+void SkPictureRecord::addNoOp() {
+    size_t size = kUInt32Size; // op
+    this->addDraw(NOOP, &size);
+}
+
 void SkPictureRecord::addRect(const SkRect& rect) {
 #ifdef SK_DEBUG_SIZE
     size_t start = fWriter.bytesWritten();
diff --git a/src/core/SkPictureRecord.h b/src/core/SkPictureRecord.h
index 0f0986fba7..22d2546072 100644
--- a/src/core/SkPictureRecord.h
+++ b/src/core/SkPictureRecord.h
@@ -89,6 +89,9 @@ public:
         fOptsEnabled = optsEnabled;
     }
 
+protected:
+    void addNoOp();
+
 private:
     void handleOptimization(int opt);
     size_t recordRestoreOffsetPlaceholder(SkRegion::Op);
diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index 08277a1ec6..f8492a7b11 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -467,6 +467,61 @@ DEF_TEST(ImageFilterMatrixTest, reporter) {
     canvas.drawPicture(*picture);
 }
 
+DEF_TEST(ImageFilterEmptySaveLayerTest, reporter) {
+
+    // Even when there's an empty saveLayer()/restore(), ensure that an image
+    // filter or color filter which affects transparent black still draws.
+
+    SkBitmap bitmap;
+    bitmap.allocN32Pixels(10, 10);
+    SkBitmapDevice device(bitmap);
+    SkCanvas canvas(&device);
+
+    SkRTreeFactory factory;
+    SkPictureRecorder recorder;
+
+    SkAutoTUnref<SkColorFilter> green(
+        SkColorFilter::CreateModeFilter(SK_ColorGREEN, SkXfermode::kSrc_Mode));
+    SkAutoTUnref<SkColorFilterImageFilter> imageFilter(
+        SkColorFilterImageFilter::Create(green.get()));
+    SkPaint imageFilterPaint;
+    imageFilterPaint.setImageFilter(imageFilter.get());
+    SkPaint colorFilterPaint;
+    colorFilterPaint.setColorFilter(green.get());
+
+    SkRect bounds = SkRect::MakeWH(10, 10);
+
+    SkCanvas* recordingCanvas = recorder.beginRecording(10, 10, &factory, 0);
+    recordingCanvas->saveLayer(&bounds, &imageFilterPaint);
+    recordingCanvas->restore();
+    SkAutoTUnref<SkPicture> picture(recorder.endRecording());
+
+    canvas.clear(0);
+    canvas.drawPicture(*picture);
+    uint32_t pixel = *bitmap.getAddr32(0, 0);
+    REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
+
+    recordingCanvas = recorder.beginRecording(10, 10, &factory, 0);
+    recordingCanvas->saveLayer(NULL, &imageFilterPaint);
+    recordingCanvas->restore();
+    SkAutoTUnref<SkPicture> picture2(recorder.endRecording());
+
+    canvas.clear(0);
+    canvas.drawPicture(*picture2);
+    pixel = *bitmap.getAddr32(0, 0);
+    REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
+
+    recordingCanvas = recorder.beginRecording(10, 10, &factory, 0);
+    recordingCanvas->saveLayer(&bounds, &colorFilterPaint);
+    recordingCanvas->restore();
+    SkAutoTUnref<SkPicture> picture3(recorder.endRecording());
+
+    canvas.clear(0);
+    canvas.drawPicture(*picture3);
+    pixel = *bitmap.getAddr32(0, 0);
+    REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
+}
+
 static void test_huge_blur(SkBaseDevice* device, skiatest::Reporter* reporter) {
     SkCanvas canvas(device);