submodule/skia/samplecode/SampleManyRects.cpp

   1 /*
   2  * Copyright 2013 Google Inc.
   3  *
   4  * Use of this source code is governed by a BSD-style license that can be
   5  * found in the LICENSE file.
   6  */
   7 #include "include/core/SkCanvas.h"
   8 #include "include/core/SkPaint.h"
   9 #include "include/core/SkShader.h"
  10 #include "include/utils/SkRandom.h"
  11 #include "samplecode/Sample.h"
  12
  13 /**
  14  * Animated sample used to develop a predecessor of GrDrawOp combining.
  15  */
  16 class ManyRectsView : public Sample {
  17 private:
  18     enum {
  19         N = 1000,
  20     };
  21
  22 public:
  23     ManyRectsView() {}
  24
  25 protected:
  26     SkString name() override { return SkString("ManyRects"); }
  27
  28     void onDrawContent(SkCanvas* canvas) override {
  29         SkISize dsize = canvas->getBaseLayerSize();
  30         canvas->clear(0xFFF0E0F0);
  31
  32         for (int i = 0; i < N; ++i) {
  33             SkRect rect = SkRect::MakeWH(SkIntToScalar(fRandom.nextRangeU(10, 100)),
  34                                          SkIntToScalar(fRandom.nextRangeU(10, 100)));
  35             int x = fRandom.nextRangeU(0, dsize.fWidth);
  36             int y = fRandom.nextRangeU(0, dsize.fHeight);
  37             canvas->save();
  38
  39             canvas->translate(SkIntToScalar(x), SkIntToScalar(y));
  40             // Uncomment to test rotated rect draw combining.
  41             if ((false)) {
  42                 SkMatrix rotate;
  43                 rotate.setRotate(fRandom.nextUScalar1() * 360,
  44                                  SkIntToScalar(x) + SkScalarHalf(rect.fRight),
  45                                  SkIntToScalar(y) + SkScalarHalf(rect.fBottom));
  46                 canvas->concat(rotate);
  47             }
  48             SkRect clipRect = rect;
  49             // This clip will always contain the entire rect. It's here to give the GPU op combining
  50             // code a little more challenge.
  51             clipRect.outset(10, 10);
  52             canvas->clipRect(clipRect);
  53             SkPaint paint;
  54             paint.setColor(fRandom.nextU());
  55             canvas->drawRect(rect, paint);
  56             canvas->restore();
  57         }
  58     }
  59
  60 private:
  61     SkRandom fRandom;
  62     using INHERITED = Sample;
  63 };
  64
  65 //////////////////////////////////////////////////////////////////////////////
  66
  67 DEF_SAMPLE( return new ManyRectsView(); )