Image filters: fix srcOffset handling in asFragmentProcessor() path.

gm/imagefiltersgraph.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 
 #include "SkArithmeticMode.h"
 #include "SkDevice.h"
 #include "SkBlurImageFilter.h"
 #include "SkColorFilter.h"
 #include "SkColorFilterImageFilter.h"
 #include "SkColorMatrixFilter.h"
 #include "SkImage.h"
 #include "SkImageSource.h"
+#include "SkMatrixConvolutionImageFilter.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 #include "SkMergeImageFilter.h"
 #include "SkMorphologyImageFilter.h"
 #include "SkTestImageFilters.h"
 #include "SkXfermodeImageFilter.h"
 
 // More closely models how Blink's OffsetFilter works as of 10/23/13. SkOffsetImageFilter doesn't
 // perform a draw and this one does.
 class SimpleOffsetFilter : public SkImageFilter {
@@ skipping 72 matching lines @@
 class ImageFiltersGraphGM : public skiagm::GM {
 public:
     ImageFiltersGraphGM() {}
 
 protected:
 
     SkString onShortName() override {
         return SkString("imagefiltersgraph");
     }
 
-    SkISize onISize() override { return SkISize::Make(500, 150); }
+    SkISize onISize() override { return SkISize::Make(600, 150); }
 
     void onOnceBeforeDraw() override {
         fImage.reset(SkImage::NewFromBitmap(
             sk_tool_utils::create_string_bitmap(100, 100, SK_ColorWHITE, 20, 70, 96, "e")));
     }
 
     void onDraw(SkCanvas* canvas) override {
         canvas->clear(SK_ColorBLACK);
         {
             SkAutoTUnref<SkImageFilter> bitmapSource(SkImageSource::Create(fImage));
@@ skipping 54 matching lines @@
             SkImageFilter::CropRect cropRect(SkRect::MakeWH(SkIntToScalar(95), SkIntToScalar(100)));
             SkAutoTUnref<SkImageFilter> blend(
                 SkXfermodeImageFilter::Create(mode, blur, nullptr, &cropRect));
 
             SkPaint paint;
             paint.setImageFilter(blend);
             DrawClippedImage(canvas, fImage, paint);
             canvas->translate(SkIntToScalar(100), 0);
         }
         {
+            // Dilate -> matrix convolution.
+            // This tests that a filter using asFragmentProcessor (matrix
+            // convolution) correctly handles a non-zero source offset
+            // (supplied by the dilate).
+            SkAutoTUnref<SkImageFilter> dilate(SkDilateImageFilter::Create(5, 5));
+
+            SkAutoTUnref<SkXfermode> mode(SkXfermode::Create(SkXfermode::kSrcIn_Mode));
+
+            SkScalar kernel[9] = {
+                SkIntToScalar(-1), SkIntToScalar( -1 ), SkIntToScalar(-1),
+                SkIntToScalar(-1), SkIntToScalar(  7 ), SkIntToScalar(-1),
+                SkIntToScalar(-1), SkIntToScalar( -1 ), SkIntToScalar(-1),
+            };
+            SkISize kernelSize = SkISize::Make(3, 3);
+            SkScalar gain = 1.0f, bias = SkIntToScalar(0);
+            SkIPoint kernelOffset = SkIPoint::Make(1, 1);
+            auto tileMode = SkMatrixConvolutionImageFilter::kClamp_TileMode;
+            bool convolveAlpha = false;
+            SkAutoTUnref<SkImageFilter> convolve(
+                SkMatrixConvolutionImageFilter::Create(kernelSize,
+                                                       kernel,
+                                                       gain,
+                                                       bias,
+                                                       kernelOffset,
+                                                       tileMode,
+                                                       convolveAlpha,
+                                                       dilate));
+
+            SkPaint paint;
+            paint.setImageFilter(convolve);
+            DrawClippedImage(canvas, fImage, paint);
+            canvas->translate(SkIntToScalar(100), 0);
+        }
+        {
             // Test that crop offsets are absolute, not relative to the parent's crop rect.
             SkAutoTUnref<SkColorFilter> cf1(SkColorFilter::CreateModeFilter(SK_ColorBLUE,
                                                                             SkXfermode::kSrcIn_Mode));
             SkAutoTUnref<SkColorFilter> cf2(SkColorFilter::CreateModeFilter(SK_ColorGREEN,
                                                                             SkXfermode::kSrcIn_Mode));
             SkImageFilter::CropRect outerRect(SkRect::MakeXYWH(SkIntToScalar(10), SkIntToScalar(10),
                                                                SkIntToScalar(80), SkIntToScalar(80)));
             SkImageFilter::CropRect innerRect(SkRect::MakeXYWH(SkIntToScalar(20), SkIntToScalar(20),
                                                                SkIntToScalar(60), SkIntToScalar(60)));
             SkAutoTUnref<SkImageFilter> color1(SkColorFilterImageFilter::Create(cf1, nullptr, &outerRect));
@@ skipping 16 matching lines @@
     }
 
     SkAutoTUnref<SkImage> fImage;
 
     typedef GM INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 DEF_GM(return new ImageFiltersGraphGM;)