1 2/* 3 * Copyright 2014 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 9#include "gm.h" 10#include "SkGradientShader.h" 11#include "SkPatchUtils.h" 12 13static SkShader* make_shader() { 14 const SkColor colors[] = { 15 SK_ColorRED, SK_ColorCYAN, SK_ColorGREEN, SK_ColorWHITE, SK_ColorMAGENTA, SK_ColorBLUE, 16 SK_ColorYELLOW, 17 }; 18 const SkPoint pts[] = { { 100.f / 4.f, 0.f }, { 3.f * 100.f / 4.f, 100.f } }; 19 20 return SkGradientShader::CreateLinear(pts, colors, NULL, SK_ARRAY_COUNT(colors), 21 SkShader::kMirror_TileMode); 22} 23 24static void draw_control_points(SkCanvas* canvas, const SkPoint cubics[12]) { 25 //draw control points 26 SkPaint paint; 27 SkPoint bottom[SkPatchUtils::kNumPtsCubic]; 28 SkPatchUtils::getBottomCubic(cubics, bottom); 29 SkPoint top[SkPatchUtils::kNumPtsCubic]; 30 SkPatchUtils::getTopCubic(cubics, top); 31 SkPoint left[SkPatchUtils::kNumPtsCubic]; 32 SkPatchUtils::getLeftCubic(cubics, left); 33 SkPoint right[SkPatchUtils::kNumPtsCubic]; 34 SkPatchUtils::getRightCubic(cubics, right); 35 36 paint.setColor(SK_ColorBLACK); 37 paint.setStrokeWidth(0.5f); 38 SkPoint corners[4] = { bottom[0], bottom[3], top[0], top[3] }; 39 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, bottom, paint); 40 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, bottom + 1, paint); 41 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, top, paint); 42 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, left, paint); 43 canvas->drawPoints(SkCanvas::kLines_PointMode, 4, right, paint); 44 45 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, top + 1, paint); 46 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, left + 1, paint); 47 canvas->drawPoints(SkCanvas::kLines_PointMode, 2, right + 1, paint); 48 49 paint.setStrokeWidth(2); 50 51 paint.setColor(SK_ColorRED); 52 canvas->drawPoints(SkCanvas::kPoints_PointMode, 4, corners, paint); 53 54 paint.setColor(SK_ColorBLUE); 55 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, bottom + 1, paint); 56 57 paint.setColor(SK_ColorCYAN); 58 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, top + 1, paint); 59 60 paint.setColor(SK_ColorYELLOW); 61 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, left + 1, paint); 62 63 paint.setColor(SK_ColorGREEN); 64 canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, right + 1, paint); 65} 66 67namespace skiagm { 68/** 69 * This GM draws a cubics coons patch using the specialized call SkCanvas::drawPatch. 70 */ 71class SkPatchGM : public GM { 72 73public: 74 SkPatchGM() { 75 this->setBGColor(0xFFFFFFFF); 76 } 77 78protected: 79 virtual SkString onShortName() SK_OVERRIDE { 80 return SkString("patch_primitive"); 81 } 82 83 virtual SkISize onISize() SK_OVERRIDE { 84 return SkISize::Make(800, 800); 85 } 86 87 virtual uint32_t onGetFlags() const SK_OVERRIDE { 88 return kSkipTiled_Flag; 89 } 90 91 virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE { 92 93 SkPaint paint; 94 95 // The order of the colors and points is clockwise starting at upper-left corner. 96 const SkPoint cubics[SkPatchUtils::kNumCtrlPts] = { 97 //top points 98 {100,100},{150,50},{250,150}, {300,100}, 99 //right points 100 {250, 150},{350,250}, 101 //bottom points 102 {300,300},{250,250},{150,350},{100,300}, 103 //left points 104 {50,250},{150,150} 105 }; 106 107 const SkColor colors[SkPatchUtils::kNumCorners] = { 108 SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorCYAN 109 }; 110 const SkPoint texCoords[SkPatchUtils::kNumCorners] = { 111 {0.0f, 0.0f}, {100.0f, 0.0f}, {100.0f,100.0f}, {0.0f, 100.0f}} 112 ; 113 114 const SkXfermode::Mode modes[] = { 115 SkXfermode::kSrc_Mode, 116 SkXfermode::kDst_Mode, 117 SkXfermode::kModulate_Mode, 118 }; 119 120 SkAutoTUnref<SkShader> shader(make_shader()); 121 122 canvas->save(); 123 for (int y = 0; y < 3; y++) { 124 SkAutoTUnref<SkXfermode> xfer(SkXfermode::Create(modes[y])); 125 126 for (int x = 0; x < 4; x++) { 127 canvas->save(); 128 canvas->translate(x * 350.0f, y * 350.0f); 129 switch (x) { 130 case 0: 131 canvas->drawPatch(cubics, NULL, NULL, xfer, paint); 132 break; 133 case 1: 134 canvas->drawPatch(cubics, colors, NULL, xfer, paint); 135 break; 136 case 2: 137 paint.setShader(shader); 138 canvas->drawPatch(cubics, NULL, texCoords, xfer, paint); 139 paint.setShader(NULL); 140 break; 141 case 3: 142 paint.setShader(shader); 143 canvas->drawPatch(cubics, colors, texCoords, xfer, paint); 144 paint.setShader(NULL); 145 break; 146 default: 147 break; 148 } 149 150 draw_control_points(canvas, cubics); 151 canvas->restore(); 152 } 153 } 154 canvas->restore(); 155 } 156 157private: 158 typedef GM INHERITED; 159}; 160 161DEF_GM(return SkNEW(SkPatchGM); ) 162 163} 164