gm/points.cpp

   1
   2 /*
   3  * Copyright 2011 Google Inc.
   4  *
   5  * Use of this source code is governed by a BSD-style license that can be
   6  * found in the LICENSE file.
   7  */
   8 #include "gm.h"
   9 #include "SkRandom.h"
  10
  11 namespace skiagm {
  12
  13 class PointsGM : public GM {
  14 public:
  15     PointsGM() {}
  16
  17 protected:
  18
  19     SkString onShortName() override {
  20         return SkString("points");
  21     }
  22
  23     SkISize onISize() override {
  24         return SkISize::Make(640, 490);
  25     }
  26
  27     static void fill_pts(SkPoint pts[], size_t n, SkRandom* rand) {
  28         for (size_t i = 0; i < n; i++) {
  29             // Compute these independently and store in variables, rather
  30             // than in the parameter-passing expression, to get consistent
  31             // evaluation order across compilers.
  32             SkScalar y = rand->nextUScalar1() * 480;
  33             SkScalar x = rand->nextUScalar1() * 640;
  34             pts[i].set(x, y);
  35         }
  36     }
  37
  38     void onDraw(SkCanvas* canvas) override {
  39         canvas->translate(SK_Scalar1, SK_Scalar1);
  40
  41         SkRandom rand;
  42         SkPaint  p0, p1, p2, p3;
  43         const size_t n = 99;
  44
  45         p0.setColor(SK_ColorRED);
  46         p1.setColor(SK_ColorGREEN);
  47         p2.setColor(SK_ColorBLUE);
  48         p3.setColor(SK_ColorWHITE);
  49
  50         p0.setStrokeWidth(SkIntToScalar(4));
  51         p2.setStrokeCap(SkPaint::kRound_Cap);
  52         p2.setStrokeWidth(SkIntToScalar(6));
  53
  54         SkPoint* pts = new SkPoint[n];
  55         fill_pts(pts, n, &rand);
  56
  57         canvas->drawPoints(SkCanvas::kPolygon_PointMode, n, pts, p0);
  58         canvas->drawPoints(SkCanvas::kLines_PointMode, n, pts, p1);
  59         canvas->drawPoints(SkCanvas::kPoints_PointMode, n, pts, p2);
  60         canvas->drawPoints(SkCanvas::kPoints_PointMode, n, pts, p3);
  61
  62         delete[] pts;
  63     }
  64
  65 private:
  66     typedef GM INHERITED;
  67 };
  68
  69 //////////////////////////////////////////////////////////////////////////////
  70
  71 static GM* MyFactory(void*) { return new PointsGM; }
  72 static GMRegistry reg(MyFactory);
  73
  74 }