Fix for SkMatrixConvolutionImageFilter with large borders.
Intersect the requested processing rect with the destination
bounds.
R=junov@chromium.org
Review URL: https://codereview.chromium.org/267863004
git-svn-id: http://skia.googlecode.com/svn/trunk@14543 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/effects/SkMatrixConvolutionImageFilter.cpp b/src/effects/SkMatrixConvolutionImageFilter.cpp
index be1dcb4..f6bc6a1 100644
--- a/src/effects/SkMatrixConvolutionImageFilter.cpp
+++ b/src/effects/SkMatrixConvolutionImageFilter.cpp
@@ -151,9 +151,10 @@
template<class PixelFetcher, bool convolveAlpha>
void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src,
SkBitmap* result,
- const SkIRect& rect,
+ const SkIRect& r,
const SkIRect& bounds) const {
- if (rect.isEmpty()) {
+ SkIRect rect(r);
+ if (!rect.intersect(bounds)) {
return;
}
for (int y = rect.fTop; y < rect.fBottom; ++y) {
diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index ffefb2c..08277a1 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -398,6 +398,38 @@
canvas.drawRect(rect, paint);
}
+DEF_TEST(ImageFilterMatrixConvolutionBorder, reporter) {
+ // Check that a filter with borders outside the target bounds
+ // does not crash.
+ SkScalar kernel[3] = {
+ 0, 0, 0,
+ };
+ SkISize kernelSize = SkISize::Make(3, 1);
+ SkScalar gain = SK_Scalar1, bias = 0;
+ SkIPoint kernelOffset = SkIPoint::Make(2, 0);
+
+ SkAutoTUnref<SkImageFilter> filter(
+ SkMatrixConvolutionImageFilter::Create(
+ kernelSize, kernel, gain, bias, kernelOffset,
+ SkMatrixConvolutionImageFilter::kClamp_TileMode, true));
+
+ SkBitmap result;
+
+ int width = 10, height = 10;
+ result.allocN32Pixels(width, height);
+ SkCanvas canvas(result);
+ canvas.clear(0);
+
+ SkPaint filterPaint;
+ filterPaint.setImageFilter(filter);
+ SkRect bounds = SkRect::MakeWH(1, 10);
+ SkRect rect = SkRect::Make(SkIRect::MakeWH(width, height));
+ SkPaint rectPaint;
+ canvas.saveLayer(&bounds, &filterPaint);
+ canvas.drawRect(rect, rectPaint);
+ canvas.restore();
+}
+
DEF_TEST(ImageFilterCropRect, reporter) {
SkBitmap temp;
temp.allocN32Pixels(100, 100);