submodule/skia/gm/colormatrix.cpp

   1 /*
   2  * Copyright 2011 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
   8 #include "gm/gm.h"
   9 #include "include/core/SkBitmap.h"
  10 #include "include/core/SkBlendMode.h"
  11 #include "include/core/SkCanvas.h"
  12 #include "include/core/SkColor.h"
  13 #include "include/core/SkColorFilter.h"
  14 #include "include/core/SkImage.h"
  15 #include "include/core/SkPaint.h"
  16 #include "include/core/SkPoint.h"
  17 #include "include/core/SkRect.h"
  18 #include "include/core/SkRefCnt.h"
  19 #include "include/core/SkScalar.h"
  20 #include "include/core/SkShader.h"
  21 #include "include/core/SkSize.h"
  22 #include "include/core/SkString.h"
  23 #include "include/core/SkTileMode.h"
  24 #include "include/core/SkTypes.h"
  25 #include "include/effects/SkColorMatrix.h"
  26 #include "include/effects/SkGradientShader.h"
  27
  28 #define WIDTH 500
  29 #define HEIGHT 160
  30
  31 static void set_color_matrix(SkPaint* paint, const SkColorMatrix& matrix) {
  32     paint->setColorFilter(SkColorFilters::Matrix(matrix));
  33 }
  34
  35 static void set_array(SkPaint* paint, const float array[]) {
  36     paint->setColorFilter(SkColorFilters::Matrix(array));
  37 }
  38
  39 class ColorMatrixGM : public skiagm::GM {
  40 public:
  41     ColorMatrixGM() {
  42         this->setBGColor(0xFF808080);
  43     }
  44
  45 protected:
  46     SkString onShortName() override {
  47         return SkString("colormatrix");
  48     }
  49
  50     SkISize onISize() override {
  51         return SkISize::Make(WIDTH, HEIGHT);
  52     }
  53
  54     void onOnceBeforeDraw() override {
  55         fSolidImg = CreateSolidBitmap(64, 64);
  56         fTransparentImg = CreateTransparentBitmap(64, 64);
  57     }
  58
  59     static sk_sp<SkImage> CreateSolidBitmap(int width, int height) {
  60         SkBitmap bm;
  61         bm.allocN32Pixels(width, height);
  62         SkCanvas canvas(bm);
  63         canvas.clear(0x0);
  64         for (int y = 0; y < height; ++y) {
  65             for (int x = 0; x < width; ++x) {
  66                 SkPaint paint;
  67                 paint.setColor(SkColorSetARGB(255, x * 255 / width, y * 255 / height, 0));
  68                 canvas.drawRect(SkRect::MakeXYWH(SkIntToScalar(x),
  69                     SkIntToScalar(y), SK_Scalar1, SK_Scalar1), paint);
  70             }
  71         }
  72         return bm.asImage();
  73     }
  74
  75     // creates a bitmap with shades of transparent gray.
  76     static sk_sp<SkImage> CreateTransparentBitmap(int width, int height) {
  77         SkBitmap bm;
  78         bm.allocN32Pixels(width, height);
  79         SkCanvas canvas(bm);
  80         canvas.clear(0x0);
  81
  82         SkPoint pts[] = {{0, 0}, {SkIntToScalar(width), SkIntToScalar(height)}};
  83         SkColor colors[] = {0x00000000, 0xFFFFFFFF};
  84         SkPaint paint;
  85         paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, 2,
  86                                                      SkTileMode::kClamp));
  87         canvas.drawRect(SkRect::MakeWH(SkIntToScalar(width), SkIntToScalar(height)), paint);
  88         return bm.asImage();
  89     }
  90
  91     void onDraw(SkCanvas* canvas) override {
  92         SkPaint paint;
  93         SkColorMatrix matrix;
  94
  95         paint.setBlendMode(SkBlendMode::kSrc);
  96         const SkImage* bmps[] = { fSolidImg.get(), fTransparentImg.get() };
  97
  98         for (size_t i = 0; i < SK_ARRAY_COUNT(bmps); ++i) {
  99             matrix.setIdentity();
 100             set_color_matrix(&paint, matrix);
 101             canvas->drawImage(bmps[i], 0, 0, SkSamplingOptions(), &paint);
 102
 103             ///////////////////////////////////////////////
 104
 105             matrix.setSaturation(0.0f);
 106             set_color_matrix(&paint, matrix);
 107             canvas->drawImage(bmps[i], 80, 0, SkSamplingOptions(), &paint);
 108
 109             matrix.setSaturation(0.5f);
 110             set_color_matrix(&paint, matrix);
 111             canvas->drawImage(bmps[i], 160, 0, SkSamplingOptions(), &paint);
 112
 113             matrix.setSaturation(1.0f);
 114             set_color_matrix(&paint, matrix);
 115             canvas->drawImage(bmps[i], 240, 0, SkSamplingOptions(), &paint);
 116
 117             matrix.setSaturation(2.0f);
 118             set_color_matrix(&paint, matrix);
 119             canvas->drawImage(bmps[i], 320, 0, SkSamplingOptions(), &paint);
 120
 121             ///////////////////////////////////////////////
 122
 123             // Move red into alpha, set color to white
 124             float data[20] = {
 125                 0,  0, 0, 0, 1,
 126                 0,  0, 0, 0, 1,
 127                 0,  0, 0, 0, 1,
 128                 1, 0, 0, 0, 0,
 129             };
 130
 131             set_array(&paint, data);
 132             canvas->drawImage(bmps[i], 400, 0, SkSamplingOptions(), &paint);
 133             ///////////////////////////////////////////////
 134             canvas->translate(0, 80);
 135         }
 136     }
 137
 138 private:
 139     sk_sp<SkImage>   fSolidImg;
 140     sk_sp<SkImage>   fTransparentImg;
 141
 142     using INHERITED = skiagm::GM;
 143 };
 144 DEF_GM( return new ColorMatrixGM; )