add compose-colorfilter

gm/tablecolorfilter.cpp

 /*
  * Copyright 2011 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 "SkCanvas.h"
 #include "SkColorFilterImageFilter.h"
 #include "SkGradientShader.h"
 #include "SkTableColorFilter.h"
 
+static SkShader* make_shader0(int w, int h) {
+    SkPoint pts[] = { {0, 0}, {SkIntToScalar(w), SkIntToScalar(h)} };
+    SkColor colors[] = {
+        SK_ColorBLACK, SK_ColorGREEN, SK_ColorCYAN,
+        SK_ColorRED, 0, SK_ColorBLUE, SK_ColorWHITE
+    };
+    return SkGradientShader::CreateLinear(pts, colors, NULL, SK_ARRAY_COUNT(colors),
+                                          SkShader::kClamp_TileMode);
+}
 static void make_bm0(SkBitmap* bm) {
     int W = 120;
     int H = 120;
     bm->allocN32Pixels(W, H);
     bm->eraseColor(SK_ColorTRANSPARENT);
 
     SkCanvas canvas(*bm);
     SkPaint paint;
-    SkPoint pts[] = { {0, 0}, {SkIntToScalar(W), SkIntToScalar(H)} };
+    paint.setShader(make_shader0(W, H))->unref();
+    canvas.drawPaint(paint);
+}
+static SkShader* make_shader1(int w, int h) {
+    SkScalar cx = SkIntToScalar(w)/2;
+    SkScalar cy = SkIntToScalar(h)/2;
     SkColor colors[] = {
-        SK_ColorBLACK, SK_ColorGREEN, SK_ColorCYAN,
-        SK_ColorRED, 0, SK_ColorBLUE, SK_ColorWHITE
+        SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE,
     };
-    SkShader* s = SkGradientShader::CreateLinear(pts, colors, NULL, SK_ARRAY_COUNT(colors),
-                                                 SkShader::kClamp_TileMode);
-    paint.setShader(s)->unref();
-    canvas.drawPaint(paint);
+    return SkGradientShader::CreateRadial(SkPoint::Make(cx, cy), cx, colors, NULL,
+                                          SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode);
 }
 static void make_bm1(SkBitmap* bm) {
     int W = 120;
     int H = 120;
+    SkScalar cx = SkIntToScalar(W)/2;
+    SkScalar cy = SkIntToScalar(H)/2;
     bm->allocN32Pixels(W, H);
     bm->eraseColor(SK_ColorTRANSPARENT);
 
     SkCanvas canvas(*bm);
     SkPaint paint;
-    SkScalar cx = SkIntToScalar(W)/2;
-    SkScalar cy = SkIntToScalar(H)/2;
-    SkColor colors[] = {
-        SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE,
-    };
-    SkShader* s = SkGradientShader::CreateRadial(SkPoint::Make(SkIntToScalar(W)/2,
-                                                               SkIntToScalar(H)/2),
-                                                 SkIntToScalar(W)/2, colors, NULL, SK_ARRAY_COUNT(colors),
-                                                 SkShader::kClamp_TileMode);
-    paint.setShader(s)->unref();
+    paint.setShader(make_shader1(W, H))->unref();
     paint.setAntiAlias(true);
     canvas.drawCircle(cx, cy, cx, paint);
 }
 
 static void make_table0(uint8_t table[]) {
     for (int i = 0; i < 256; ++i) {
         int n = i >> 5;
         table[i] = (n << 5) | (n << 2) | (n >> 1);
     }
 }
@@ skipping 117 matching lines @@
             }
 
             // Move down one line to the beginning of the block for next bitmap
             y += yOffset;
         }
     }
 
 private:
     typedef GM INHERITED;
 };
+DEF_GM( return new TableColorFilterGM; )
 
 //////////////////////////////////////////////////////////////////////////////
 
-static skiagm::GM* MyFactory(void*) { return new TableColorFilterGM; }
-static skiagm::GMRegistry reg(MyFactory);
+class ComposeColorFilterGM : public skiagm::GM {
+public:
+    ComposeColorFilterGM() {}
+    
+protected:
+    virtual SkString onShortName() {
+        return SkString("composecolorfilter");
+    }
+    
+    virtual SkISize onISize() {
+        return SkISize::Make(730, 730);
+    }
+
+    virtual void onDraw(SkCanvas* canvas) {
+        SkBitmap bm;
+        make_bm1(&bm);
+
+        canvas->drawColor(0xFFDDDDDD);
+
+        SkColor colors[] = { SK_ColorCYAN, SK_ColorMAGENTA, SK_ColorYELLOW };
+        SkXfermode::Mode modes[] = {
+            SkXfermode::kOverlay_Mode,
+            SkXfermode::kDarken_Mode,
+            SkXfermode::kColorBurn_Mode,
+            SkXfermode::kExclusion_Mode,
+        };
+
+        const int MODES = SK_ARRAY_COUNT(modes) * SK_ARRAY_COUNT(colors);
+        SkAutoTUnref<SkColorFilter> filters[MODES];
+        int index = 0;
+        for (size_t i = 0; i < SK_ARRAY_COUNT(modes); ++i) {
+            for (size_t j = 0; j < SK_ARRAY_COUNT(colors); ++j) {
+                filters[index++].reset(SkColorFilter::CreateModeFilter(colors[j], modes[i]));
+            }
+        }
+
+        SkPaint paint;
+        paint.setShader(make_shader1(50, 50))->unref();
+        SkRect r = SkRect::MakeWH(50, 50);
+        const SkScalar spacer = 10;
+
+        canvas->translate(spacer, spacer);
+
+        for (size_t y = 0; y < MODES; ++y) {
+            canvas->save();
+            for (size_t x = 0; x < MODES; ++x) {
+                SkAutoTUnref<SkColorFilter> compose(SkColorFilter::CreateComposeFilter(filters[y],
+                                                                                       filters[x]));
+                paint.setColorFilter(compose);
+                canvas->drawRect(r, paint);
+                canvas->translate(r.width() + spacer, 0);
+            }
+            canvas->restore();
+            canvas->translate(0, r.height() + spacer);
+        }
+    }
+    
+private:
+    typedef GM INHERITED;
+};
+DEF_GM( return new ComposeColorFilterGM; )
+