Implement srcRect and dstRect functionality in SkBitmapSource. This is required for the "preserveAs…

gm/xfermodeimagefilter.cpp

 /*
  * Copyright 2013 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 "SkOffsetImageFilter.h"
 #include "SkXfermodeImageFilter.h"
 #include "SkBitmapSource.h"
 
 #define WIDTH 600
 #define HEIGHT 600
 #define MARGIN 12
 
 namespace skiagm {
 
 class XfermodeImageFilterGM : public GM {
 public:
-    XfermodeImageFilterGM() : fInitialized(false) {
+    XfermodeImageFilterGM(){
         this->setBGColor(0xFF000000);
     }
 
 protected:
-    virtual SkString onShortName() {
+    virtual SkString onShortName() SK_OVERRIDE {
         return SkString("xfermodeimagefilter");
     }
 
     void make_bitmap() {
         fBitmap.setConfig(SkBitmap::kARGB_8888_Config, 80, 80);
         fBitmap.allocPixels();
         SkBitmapDevice device(fBitmap);
         SkCanvas canvas(&device);
         canvas.clear(0x00000000);
         SkPaint paint;
@@ skipping 20 matching lines @@
             canvas.translate(SkIntToScalar(x), SkIntToScalar(y));
             canvas.drawRect(SkRect::MakeXYWH(0, 0, 8, 8), darkPaint);
             canvas.drawRect(SkRect::MakeXYWH(8, 0, 8, 8), lightPaint);
             canvas.drawRect(SkRect::MakeXYWH(0, 8, 8, 8), lightPaint);
             canvas.drawRect(SkRect::MakeXYWH(8, 8, 8, 8), darkPaint);
             canvas.restore();
           }
         }
     }
 
-    virtual SkISize onISize() {
+    virtual SkISize onISize() SK_OVERRIDE {
         return make_isize(WIDTH, HEIGHT);
     }
 
-    void drawClippedBitmap(SkCanvas* canvas, const SkBitmap& bitmap, const SkPaint& paint,
-                           SkScalar x, SkScalar y) {
+    static void drawClippedBitmap(SkCanvas* canvas, const SkBitmap& bitmap, const SkPaint& paint,
+                           int x, int y) {
         canvas->save();
-        canvas->clipRect(SkRect::MakeXYWH(x, y,
+        canvas->translate(SkIntToScalar(x), SkIntToScalar(y));
+        canvas->clipRect(SkRect::MakeWH(
             SkIntToScalar(bitmap.width()), SkIntToScalar(bitmap.height())));
-        canvas->drawBitmap(bitmap, x, y, &paint);
+        canvas->drawBitmap(bitmap, 0, 0, &paint);
         canvas->restore();
     }
 
-    virtual void onDraw(SkCanvas* canvas) {
-        if (!fInitialized) {
-            make_bitmap();
-            make_checkerboard();
-            fInitialized = true;
-        }
+    static void drawClippedPaint(SkCanvas* canvas, const SkRect& rect, const SkPaint& paint,
+                          int x, int y) {
+        canvas->save();
+        canvas->translate(SkIntToScalar(x), SkIntToScalar(y));
+        canvas->clipRect(rect);
+        canvas->drawPaint(paint);
+        canvas->restore();
+    }
+
+    virtual void onOnceBeforeDraw() SK_OVERRIDE {
+        make_bitmap();
+        make_checkerboard();
+    }
+
+    virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
         canvas->clear(0x00000000);
         SkPaint paint;
 
         const struct {
             SkXfermode::Mode  fMode;
             const char*         fLabel;
         } gModes[] = {
             { SkXfermode::kClear_Mode,    "Clear"     },
             { SkXfermode::kSrc_Mode,      "Src"       },
             { SkXfermode::kDst_Mode,      "Dst"       },
@@ skipping 26 matching lines @@
             { SkXfermode::kLuminosity_Mode,   "Luminosity"    },
         };
 
         int x = 0, y = 0;
         SkAutoTUnref<SkImageFilter> background(SkNEW_ARGS(SkBitmapSource, (fCheckerboard)));
         for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); i++) {
             SkAutoTUnref<SkXfermode> mode(SkXfermode::Create(gModes[i].fMode));
             SkAutoTUnref<SkImageFilter> filter(SkNEW_ARGS(
                 SkXfermodeImageFilter, (mode, background)));
             paint.setImageFilter(filter);
-            drawClippedBitmap(canvas, fBitmap, paint, SkIntToScalar(x), SkIntToScalar(y));
+            drawClippedBitmap(canvas, fBitmap, paint, x, y);
             x += fBitmap.width() + MARGIN;
             if (x + fBitmap.width() > WIDTH) {
                 x = 0;
                 y += fBitmap.height() + MARGIN;
             }
         }
         // Test arithmetic mode as image filter
         SkAutoTUnref<SkXfermode> mode(SkArithmeticMode::Create(0, SK_Scalar1, SK_Scalar1, 0));
         SkAutoTUnref<SkImageFilter> filter(SkNEW_ARGS(SkXfermodeImageFilter, (mode, background)));
         paint.setImageFilter(filter);
-        drawClippedBitmap(canvas, fBitmap, paint, SkIntToScalar(x), SkIntToScalar(y));
+        drawClippedBitmap(canvas, fBitmap, paint, x, y);
         x += fBitmap.width() + MARGIN;
         if (x + fBitmap.width() > WIDTH) {
             x = 0;
             y += fBitmap.height() + MARGIN;
         }
         // Test NULL mode
         filter.reset(SkNEW_ARGS(SkXfermodeImageFilter, (NULL, background)));
         paint.setImageFilter(filter);
-        drawClippedBitmap(canvas, fBitmap, paint, SkIntToScalar(x), SkIntToScalar(y));
+        drawClippedBitmap(canvas, fBitmap, paint, x, y);
         x += fBitmap.width() + MARGIN;
         if (x + fBitmap.width() > WIDTH) {
             x = 0;
             y += fBitmap.height() + MARGIN;
         }
+        SkRect clipRect = SkRect::MakeWH(SkIntToScalar(fBitmap.width() + 4),
+                                         SkIntToScalar(fBitmap.height() + 4));
         // Test offsets on SrcMode (uses fixed-function blend)
         SkAutoTUnref<SkImageFilter> foreground(SkNEW_ARGS(SkBitmapSource, (fBitmap)));
         SkAutoTUnref<SkImageFilter> offsetForeground(SkNEW_ARGS(SkOffsetImageFilter,
             (SkIntToScalar(4), SkIntToScalar(-4), foreground)));
         SkAutoTUnref<SkImageFilter> offsetBackground(SkNEW_ARGS(SkOffsetImageFilter,
             (SkIntToScalar(4), SkIntToScalar(4), background)));
         mode.reset(SkXfermode::Create(SkXfermode::kSrcOver_Mode));
         filter.reset(SkNEW_ARGS(SkXfermodeImageFilter,
             (mode, offsetBackground, offsetForeground)));
         paint.setImageFilter(filter);
-        canvas->save();
-        canvas->clipRect(SkRect::MakeXYWH(SkIntToScalar(x),
-                                          SkIntToScalar(y),
-                                          SkIntToScalar(fBitmap.width() + 4),
-                                          SkIntToScalar(fBitmap.height() + 4)));
-        canvas->drawPaint(paint);
-        canvas->restore();
+        drawClippedPaint(canvas, clipRect, paint, x, y);
         x += fBitmap.width() + MARGIN;
         if (x + fBitmap.width() > WIDTH) {
             x = 0;
             y += fBitmap.height() + MARGIN;
         }
         // Test offsets on Darken (uses shader blend)
         mode.reset(SkXfermode::Create(SkXfermode::kDarken_Mode));
         filter.reset(SkNEW_ARGS(SkXfermodeImageFilter, (mode, offsetBackground, offsetForeground)));
         paint.setImageFilter(filter);
-        canvas->save();
-        canvas->clipRect(SkRect::MakeXYWH(SkIntToScalar(x),
-                                          SkIntToScalar(y),
-                                          SkIntToScalar(fBitmap.width() + 4),
-                                          SkIntToScalar(fBitmap.height() + 4)));
-        canvas->drawPaint(paint);
-        canvas->restore();
+        drawClippedPaint(canvas, clipRect, paint, x, y);
         x += fBitmap.width() + MARGIN;
         if (x + fBitmap.width() > WIDTH) {
             x = 0;
             y += fBitmap.height() + MARGIN;
         }
         // Test cropping
         static const size_t nbSamples = 3;
         SkXfermode::Mode sampledModes[nbSamples] = {SkXfermode::kOverlay_Mode,
                                                     SkXfermode::kSrcOver_Mode,
                                                     SkXfermode::kPlus_Mode};
         int offsets[nbSamples][4] = {{ 10,  10, -16, -16},
                                      { 10,  10,  10,  10},
                                      {-10, -10,  -6,  -6}};
         for (size_t i = 0; i < nbSamples; ++i) {
-            SkIRect cropRect = SkIRect::MakeXYWH(x + offsets[i][0],
-                                                 y + offsets[i][1],
+            SkIRect cropRect = SkIRect::MakeXYWH(offsets[i][0],
+                                                 offsets[i][1],
                                                  fBitmap.width()  + offsets[i][2],
                                                  fBitmap.height() + offsets[i][3]);
             SkImageFilter::CropRect rect(SkRect::Make(cropRect));
             mode.reset(SkXfermode::Create(sampledModes[i]));
             filter.reset(SkNEW_ARGS(SkXfermodeImageFilter,
                                     (mode, offsetBackground, offsetForeground, &rect)));
             paint.setImageFilter(filter);
-            canvas->save();
-            canvas->clipRect(SkRect::MakeXYWH(SkIntToScalar(x),
-                                              SkIntToScalar(y),
-                                              SkIntToScalar(fBitmap.width() + 4),
-                                              SkIntToScalar(fBitmap.height() + 4)));
-            canvas->drawPaint(paint);
-            canvas->restore();
+            drawClippedPaint(canvas, clipRect, paint, x, y);
             x += fBitmap.width() + MARGIN;
             if (x + fBitmap.width() > WIDTH) {
                 x = 0;
                 y += fBitmap.height() + MARGIN;
             }
         }
     }
 private:
+    SkBitmap fBitmap, fCheckerboard;
     typedef GM INHERITED;
-    SkBitmap fBitmap, fCheckerboard;
-    bool fInitialized;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
-static GM* MyFactory(void*) { return new XfermodeImageFilterGM; }
-static GMRegistry reg(MyFactory);
+DEF_GM( return new XfermodeImageFilterGM; );
 
 }