Implement crop rect for SkImageFilter

gm/imagefilterscropped.cpp

Index: gm/imagefilterscropped.cpp
diff --git a/gm/imagefiltersbase.cpp b/gm/imagefilterscropped.cpp
similarity index 71%
copy from gm/imagefiltersbase.cpp
copy to gm/imagefilterscropped.cpp
index 6879e796b1aa0a30b1d7d30024ef6d8bd01ca8c3..2460f2af0ba2d770e0d4d053dad19d7924850eb8 100644
--- a/gm/imagefiltersbase.cpp
+++ b/gm/imagefilterscropped.cpp
@@ -15,56 +15,12 @@
 #include "SkColorFilterImageFilter.h"
 #include "SkTestImageFilters.h"
 
-class FailImageFilter : public SkImageFilter {
-public:
-    FailImageFilter() : INHERITED(0) {}
-
-    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(FailImageFilter)
-protected:
-    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
-                               SkBitmap* result, SkIPoint* offset) {
-        return false;
-    }
-
-    FailImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
-
-private:
-    typedef SkImageFilter INHERITED;
-};
-
-// register the filter with the flattenable registry
-static SkFlattenable::Registrar gFailImageFilterReg("FailImageFilter",
-                                                    FailImageFilter::CreateProc);
-
-class IdentityImageFilter : public SkImageFilter {
-public:
-    IdentityImageFilter() : INHERITED(0) {}
-
-    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(IdentityImageFilter)
-protected:
-    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
-                               SkBitmap* result, SkIPoint* offset) {
-        *result = src;
-        return true;
-    }
-
-    IdentityImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
-
-private:
-    typedef SkImageFilter INHERITED;
-};
-
-// register the filter with the flattenable registry
-static SkFlattenable::Registrar gIdentityImageFilterReg("IdentityImageFilter",
-                                                        IdentityImageFilter::CreateProc);
-
-
 ///////////////////////////////////////////////////////////////////////////////
 
 static void draw_paint(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     SkPaint paint;
     paint.setImageFilter(imf);
-    paint.setColor(SK_ColorGREEN);
+    paint.setColor(SK_ColorBLACK);
     canvas->save();
     canvas->clipRect(r);
     canvas->drawPaint(paint);
@@ -76,7 +32,10 @@ static void draw_line(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     paint.setColor(SK_ColorBLUE);
     paint.setImageFilter(imf);
     paint.setStrokeWidth(r.width()/10);
+    canvas->save();
+    canvas->clipRect(r);
     canvas->drawLine(r.fLeft, r.fTop, r.fRight, r.fBottom, paint);
+    canvas->restore();
 }
 
 static void draw_rect(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
@@ -85,7 +44,10 @@ static void draw_rect(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     paint.setImageFilter(imf);
     SkRect rr(r);
     rr.inset(r.width()/10, r.height()/10);
+    canvas->save();
+    canvas->clipRect(r);
     canvas->drawRect(rr, paint);
+    canvas->restore();
 }
 
 static void draw_path(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
@@ -93,22 +55,27 @@ static void draw_path(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     paint.setColor(SK_ColorMAGENTA);
     paint.setImageFilter(imf);
     paint.setAntiAlias(true);
+    canvas->save();
+    canvas->clipRect(r);
     canvas->drawCircle(r.centerX(), r.centerY(), r.width()*2/5, paint);
+    canvas->restore();
 }
 
 static void draw_text(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     SkPaint paint;
     paint.setImageFilter(imf);
-    paint.setColor(SK_ColorCYAN);
+    paint.setColor(SK_ColorGREEN);
     paint.setAntiAlias(true);
     paint.setTextSize(r.height()/2);
     paint.setTextAlign(SkPaint::kCenter_Align);
+    canvas->save();
+    canvas->clipRect(r);
     canvas->drawText("Text", 4, r.centerX(), r.centerY(), paint);
+    canvas->restore();
 }
 
 static void draw_bitmap(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     SkPaint paint;
-    paint.setImageFilter(imf);
 
     SkIRect bounds;
     r.roundOut(&bounds);
@@ -120,12 +87,15 @@ static void draw_bitmap(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     SkCanvas c(bm);
     draw_path(&c, r, NULL);
 
+    paint.setImageFilter(imf);
+    canvas->save();
+    canvas->clipRect(r);
     canvas->drawBitmap(bm, 0, 0, &paint);
+    canvas->restore();
 }
 
 static void draw_sprite(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     SkPaint paint;
-    paint.setImageFilter(imf);
 
     SkIRect bounds;
     r.roundOut(&bounds);
@@ -133,10 +103,14 @@ static void draw_sprite(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
     SkBitmap bm;
     bm.setConfig(SkBitmap::kARGB_8888_Config, bounds.width(), bounds.height());
     bm.allocPixels();
-    bm.eraseColor(SK_ColorTRANSPARENT);
+    bm.eraseColor(SK_ColorRED);
     SkCanvas c(bm);
-    draw_path(&c, r, NULL);
+    
+    SkIRect cropRect = SkIRect::MakeXYWH(10, 10, 44, 44);
+    paint.setColor(SK_ColorGREEN);
+    c.drawRect(SkRect::Make(cropRect), paint);
 
+    paint.setImageFilter(imf);
     SkPoint loc = { r.fLeft, r.fTop };
     canvas->getTotalMatrix().mapPoints(&loc, 1);
     canvas->drawSprite(bm,
@@ -146,14 +120,14 @@ static void draw_sprite(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
 
 ///////////////////////////////////////////////////////////////////////////////
 
-class ImageFiltersBaseGM : public skiagm::GM {
+class ImageFiltersCroppedGM : public skiagm::GM {
 public:
-    ImageFiltersBaseGM () {}
+    ImageFiltersCroppedGM () {}
 
 protected:
 
     virtual SkString onShortName() {
-        return SkString("imagefiltersbase");
+        return SkString("imagefilterscropped");
     }
 
     virtual SkISize onISize() { return SkISize::Make(700, 460); }
@@ -183,12 +157,14 @@ protected:
 
         SkColorFilter* cf = SkColorFilter::CreateModeFilter(SK_ColorRED,
                                                      SkXfermode::kSrcIn_Mode);
+        SkIRect cropRect = SkIRect::MakeXYWH(10, 10, 44, 44);
+
         SkImageFilter* filters[] = {
             NULL,
-            new IdentityImageFilter,
-            new FailImageFilter,
-            SkColorFilterImageFilter::Create(cf),
-            new SkBlurImageFilter(12.0f, 0.0f),
+            SkColorFilterImageFilter::Create(cf, NULL, &cropRect),
+            new SkBlurImageFilter(8.0f, 0.0f, NULL, &cropRect),
+            new SkBlurImageFilter(0.0f, 8.0f, NULL, &cropRect),
+            new SkBlurImageFilter(8.0f, 8.0f, NULL, &cropRect),
         };
         cf->unref();
 
@@ -202,8 +178,6 @@ protected:
             canvas->save();
             for (size_t j = 0; j < SK_ARRAY_COUNT(filters); ++j) {
                 drawProc[i](canvas, r, filters[j]);
-
-                draw_frame(canvas, r);
                 canvas->translate(0, DY);
             }
             canvas->restore();
@@ -221,5 +195,5 @@ private:
 
 ///////////////////////////////////////////////////////////////////////////////
 
-static skiagm::GM* MyFactory(void*) { return new ImageFiltersBaseGM; }
+static skiagm::GM* MyFactory(void*) { return new ImageFiltersCroppedGM; }
 static skiagm::GMRegistry reg(MyFactory);