add applyFilter() to SkImage

gm/spritebitmap.cpp

Index: gm/spritebitmap.cpp
diff --git a/gm/spritebitmap.cpp b/gm/spritebitmap.cpp
index ceed50acaac31504488fe44486733171073709e1..4424001cf5231246d9a2db091dac01712db288d4 100644
--- a/gm/spritebitmap.cpp
+++ b/gm/spritebitmap.cpp
@@ -97,3 +97,109 @@ private:
 };
 DEF_GM( return new SpriteBitmapGM; )
 
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include "SkColorFilterImageFilter.h"
+#include "SkModeColorFilter.h"
+#include "SkMorphologyImageFilter.h"
+#include "SkOffsetImageFilter.h"
+
+static SkImage* make_image(SkCanvas* rootCanvas) {
+    SkImageInfo info = SkImageInfo::MakeN32Premul(100, 100);
+    SkAutoTUnref<SkSurface> surface(rootCanvas->newSurface(info));
+    if (!surface) {
+        surface.reset(SkSurface::NewRaster(info));
+    }
+
+    SkPaint paint;
+    paint.setAntiAlias(true);
+    paint.setColor(SK_ColorRED);
+    surface->getCanvas()->drawCircle(50, 50, 50, paint);
+    return surface->newImageSnapshot();
+}
+
+static void show_image(SkCanvas* canvas, SkImage* image, const SkIPoint& offset) {
+    SkScalar x = SkIntToScalar(offset.x());
+    SkScalar y = SkIntToScalar(offset.y());
+
+    SkPaint paint;

[robertphillips, 2015/10/12 16:43:32]

sk_tool_utils::color_to_565 ?

[reed1, 2015/10/12 18:02:19]

Done.

+    paint.setColor(0xFFEEEEEE);
+
+    SkRect r = SkRect::MakeIWH(image->width(), image->height());
+    r.offset(x, y);
+    canvas->drawRect(r, paint);
+
+    canvas->drawImage(image, x, y, nullptr);
+}
+
+typedef SkImageFilter* (*ImageFilterFactory)();
+
+/**
+ *  Compare output of drawSprite and drawBitmap (esp. clipping and imagefilters)
+ */
+class ApplyFilterGM : public skiagm::GM {
+public:
+    ApplyFilterGM() {}
+
+protected:
+    SkString onShortName() override {
+        return SkString("apply-filter");
+    }
+
+    SkISize onISize() override {
+        return SkISize::Make(640, 480);
+    }
+
+    void onDraw(SkCanvas* canvas) override {
+        SkAutoTUnref<SkImage> image0(make_image(canvas));
+
+        const ImageFilterFactory factories[] = {
+            (ImageFilterFactory)[]{ return SkBlurImageFilter::Create(8, 8); },
+            (ImageFilterFactory)[]{ SkAutoTUnref<SkColorFilter> cf(new SkModeColorFilter(SK_ColorBLUE,
+                                                                     SkXfermode::kSrcIn_Mode));
+                 return (SkImageFilter*)SkColorFilterImageFilter::Create(cf);
+            },
+            (ImageFilterFactory)[]{ return SkDilateImageFilter::Create(8, 8); },
+            (ImageFilterFactory)[]{ return SkErodeImageFilter::Create(8, 8); },
+            (ImageFilterFactory)[]{ return SkOffsetImageFilter::Create(8, 8); },
+        };
+
+        for (auto&& factory : factories) {
+            SkAutoTUnref<SkImageFilter> filter(factory());
+

[robertphillips, 2015/10/12 16:43:32]

put "offset1.setZero();" on its own line or use "= { 0, 0 }" ?

[reed1, 2015/10/12 18:02:19]

Done.

+            SkIPoint offset1, offset2; offset1.setZero();
+            SkAutoTUnref<SkImage> image1(image0->applyFilter(filter, &offset1, true));
+            SkAutoTUnref<SkImage> image2(image0->applyFilter(filter, &offset2, false));
+
+            canvas->save();
+            canvas->translate(30, 30);
+            show_image(canvas, image0, SkIPoint::Make(0, 0));

[robertphillips, 2015/10/12 16:43:32]

150 -> kImageWHWithPath ?

[reed1, 2015/10/12 18:02:19]

Done.

+            canvas->translate(150, 0);
+            show_image(canvas, image1, offset1);
+            canvas->translate(150, 0);
+            show_image(canvas, image2, offset2);
+            {

[robertphillips, 2015/10/12 16:43:32]

// draw with old paths (drawSprite & drawImage w/ filter) for comparison ?

[reed1, 2015/10/12 18:02:19]

Done.

+                SkPaint paint;
+                paint.setImageFilter(filter);
+
+                SkBitmap bm;
+                image0->asLegacyBitmap(&bm, SkImage::kRO_LegacyBitmapMode);
+                SkPoint loc = { 0, 0 };
+                canvas->translate(150, 0);
+                canvas->getTotalMatrix().mapPoints(&loc, 1);
+                canvas->drawSprite(bm, (int)loc.x(), (int)loc.y(), &paint);
+
+                canvas->translate(150, 0);
+                canvas->drawImage(image0, 0, 0, &paint);
+            }
+            canvas->restore();
+
+            canvas->translate(0, 150);
+        }
+    }
+
+private:
+    typedef GM INHERITED;
+};
+DEF_GM( return new ApplyFilterGM; )
+