extend xfermodes gm to include 3 custom modes

gm/xfermodes.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 "SkBitmap.h"
 #include "SkShader.h"
 #include "SkXfermode.h"
 #include "SkPM4f.h"
 
+#include "SkArithmeticMode.h"
+#include "SkPixelXorXfermode.h"
+#include "SkAvoidXfermode.h"
+
+#define kCustomShift    16
+#define kCustomMask     (~0xFFFF)
+
+enum CustomModes {
+    kArithmetic_CustomMode  = 1 << kCustomShift,
+    kPixelXor_CustomMode    = 2 << kCustomShift,
+    kAvoid_CustomMode       = 3 << kCustomShift,
+};
+
+static SkXfermode* make_custom(int customMode) {
+    switch (customMode) {
+        case kArithmetic_CustomMode: {
+            const SkScalar k1 = 0.25;
+            const SkScalar k2 = 0.75;
+            const SkScalar k3 = 0.75;
+            const SkScalar k4 = -0.25;
+            return SkArithmeticMode::Create(k1, k2, k3, k4);
+        }
+        case kPixelXor_CustomMode:
+            return SkPixelXorXfermode::Create(0xFF88CC44);
+        case kAvoid_CustomMode:
+            return SkAvoidXfermode::Create(0xFFFF0000, 0x44, SkAvoidXfermode::kAvoidColor_Mode);
+        default:
+            break;
+    }
+    SkASSERT(false);
+    return nullptr;
+}
+
 enum SrcType {
     //! A WxH image with a rectangle in the lower right.
     kRectangleImage_SrcType               = 0x01,
     //! kRectangleImage_SrcType with an alpha of 34.5%.
     kRectangleImageWithAlpha_SrcType      = 0x02,
     //! kRectnagleImageWithAlpha_SrcType scaled down by half.
     kSmallRectangleImageWithAlpha_SrcType = 0x04,
     //! kRectangleImage_SrcType drawn directly instead in an image.
     kRectangle_SrcType                    = 0x08,
     //! Two rectangles, first on the right half, second on the bottom half.
@@ skipping 42 matching lines @@
     { SkXfermode::kColorBurn_Mode,    "ColorBurn",    kBasic_SrcType },
     { SkXfermode::kHardLight_Mode,    "HardLight",    kBasic_SrcType },
     { SkXfermode::kSoftLight_Mode,    "SoftLight",    kBasic_SrcType },
     { SkXfermode::kDifference_Mode,   "Difference",   kBasic_SrcType },
     { SkXfermode::kExclusion_Mode,    "Exclusion",    kBasic_SrcType },
     { SkXfermode::kMultiply_Mode,     "Multiply",     kAll_SrcType   },
     { SkXfermode::kHue_Mode,          "Hue",          kBasic_SrcType },
     { SkXfermode::kSaturation_Mode,   "Saturation",   kBasic_SrcType },
     { SkXfermode::kColor_Mode,        "Color",        kBasic_SrcType },
     { SkXfermode::kLuminosity_Mode,   "Luminosity",   kBasic_SrcType },
+
+    { SkXfermode::Mode(0xFFFF),       "Arithmetic",   kBasic_SrcType + kArithmetic_CustomMode   },
+    { SkXfermode::Mode(0xFFFF),       "PixelXor",     kBasic_SrcType + kPixelXor_CustomMode     },
+    { SkXfermode::Mode(0xFFFF),       "Avoid",        kBasic_SrcType + kAvoid_CustomMode        },
 };
 
 static void make_bitmaps(int w, int h, SkBitmap* src, SkBitmap* dst,
                          SkBitmap* transparent) {
     src->allocN32Pixels(w, h);
     src->eraseColor(SK_ColorTRANSPARENT);
 
     SkPaint p;
     p.setAntiAlias(true);
 
@@ skipping 121 matching lines @@
     const static int W = 64;
     const static int H = 64;
     XfermodesGM() {}
 
 protected:
     SkString onShortName() override {
         return SkString("xfermodes");
     }
 
     SkISize onISize() override {
-        return SkISize::Make(1990, 640);
+        return SkISize::Make(1990, 660);
     }
 
     void onDraw(SkCanvas* canvas) override {
         canvas->translate(SkIntToScalar(10), SkIntToScalar(20));
 
         const SkScalar w = SkIntToScalar(W);
         const SkScalar h = SkIntToScalar(H);
         SkMatrix m;
         m.setScale(SkIntToScalar(6), SkIntToScalar(6));
         SkShader* s = SkShader::CreateBitmapShader(fBG,
                                                    SkShader::kRepeat_TileMode,
                                                    SkShader::kRepeat_TileMode,
                                                    &m);
 
         SkPaint labelP;
         labelP.setAntiAlias(true);
         sk_tool_utils::set_portable_typeface(&labelP);
         labelP.setTextAlign(SkPaint::kCenter_Align);
 
         const int W = 5;
 
         SkScalar x0 = 0;
         SkScalar y0 = 0;
         for (int sourceType = 1; sourceType & kAll_SrcType; sourceType <<= 1) {
             SkScalar x = x0, y = y0;
             for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); i++) {
                 if ((gModes[i].fSourceTypeMask & sourceType) == 0) {
+                    SkDebugf("skip %d %s for type %x\n", i, gModes[i].fLabel, sourceType);
                     continue;
                 }
-                SkXfermode* mode = SkXfermode::Create(gModes[i].fMode);
-                SkAutoUnref aur(mode);
+                SkAutoTUnref<SkXfermode> mode;
+                if (gModes[i].fSourceTypeMask & kCustomMask) {
+                    mode.reset(make_custom(gModes[i].fSourceTypeMask & kCustomMask));
+                } else {
+                    mode.reset(SkXfermode::Create(gModes[i].fMode));
+                }
                 SkRect r;
                 r.set(x, y, x+w, y+h);
 
                 SkPaint p;
                 p.setStyle(SkPaint::kFill_Style);
                 p.setShader(s);
                 canvas->drawRect(r, p);
 
                 canvas->saveLayer(&r, nullptr);
                 draw_mode(canvas, mode, static_cast<SrcType>(sourceType),
@@ skipping 25 matching lines @@
                 y0 = 0;
             }
         }
         s->unref();
     }
 
 private:
     typedef GM INHERITED;
 };
 DEF_GM( return new XfermodesGM; )