remove randomness in dstreadshuffle

gm/dstreadshuffle.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 "SkBitmap.h"
 #include "SkRandom.h"
@@ skipping 76 matching lines @@
             case kText_ShapeType: {
                 const char* text = "Hello!";
                 paint->setTextSize(30);
                 canvas->drawText(text, strlen(text), 0, 0, *paint);
             }
             default:
                 break;
         }
     }
 
-    static SkColor GetColor(SkRandom* random, int i) {
+    static SkColor GetColor(SkRandom* random, int i, int nextColor) {
+        static SkColor colors[] = { SK_ColorRED,
+                                    0xFFFF7F00, // Orange
+                                    SK_ColorYELLOW,
+                                    SK_ColorGREEN,
+                                    SK_ColorBLUE,
+                                    0xFF4B0082, // indigo
+                                    0xFF7F00FF }; // violet
         SkColor color;
+        int index = nextColor % SK_ARRAY_COUNT(colors);
         switch (i) {
             case 0:
                 color = SK_ColorTRANSPARENT;
                 break;
             case 1:
                 color = SkColorSetARGB(0xff,
-                                       random->nextULessThan(256),
-                                       random->nextULessThan(256),
-                                       random->nextULessThan(256));
+                                       SkColorGetR(colors[index]),
+                                       SkColorGetG(colors[index]),
+                                       SkColorGetB(colors[index]));
                 break;
             default:
-                uint8_t alpha = random->nextULessThan(256);
+                uint8_t alpha = 0x80;
                 color = SkColorSetARGB(alpha,
-                                       random->nextRangeU(0, alpha),
-                                       random->nextRangeU(0, alpha),
-                                       random->nextRangeU(0, alpha));
+                                       SkColorGetR(colors[index]),
+                                       SkColorGetG(colors[index]),
+                                       SkColorGetB(colors[index]));
                 break;
         }
         return color;
     }
 
     static void SetStyle(SkPaint* p, int style, int width) {
         switch (style) {
             case 0:
                 p->setStyle(SkPaint::kStroke_Style);
                 p->setStrokeWidth((SkScalar)width);
@@ skipping 11 matching lines @@
     void onDraw(SkCanvas* canvas) override {
         SkRandom random;
         SkScalar y = 100;
         for (int i = 0; i < kNumShapeTypes; i++) {
             ShapeType shapeType = static_cast<ShapeType>(i);
             SkScalar x = 25;
             for (int style = 0; style < 3; style++) {
                 for (int width = 0; width <= 1; width++) {
                     for (int alpha = 0; alpha <= 2; alpha++) {
                         for (int r = 0; r <= 5; r++) {
-                            SkColor color = GetColor(&random, alpha);
+                            SkColor color = GetColor(&random, alpha, style + width + alpha + r);
 
                             SkPaint p;
                             p.setAntiAlias(true);
                             p.setColor(color);
-                            p.setXfermodeMode(r % 3 == 0 ? SkXfermode::kHardLight_Mode :
+                            // In order to get some batching on the GPU backend we do 2 src over for
+                            // each xfer mode which requires a dst read
+                            p.setXfermodeMode(r % 3 == 0 ? SkXfermode::kLighten_Mode :
                                                            SkXfermode::kSrcOver_Mode);
                             SetStyle(&p, style, width);
                             canvas->save();
                             canvas->translate(x, y);
                             canvas->rotate((SkScalar)(r < 3 ? 10 : 0));
                             this->drawShape(canvas, &p, shapeType);
                             canvas->restore();
                             x += 8;
                         }
                     }
@@ skipping 14 matching lines @@
     static const int kHeight = 400;
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 static GM* MyFactory(void*) { return new DstReadShuffle; }
 static GMRegistry reg(MyFactory);
 
 }