1 /* 2 * Copyright 2015 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.h" 9 #include "SkCanvas.h" 10 #include "SkRSXform.h" 11 #include "SkSurface.h" 12 13 class DrawAtlasGM : public skiagm::GM { MakeAtlas(SkCanvas * caller,const SkRect & target)14 static SkImage* MakeAtlas(SkCanvas* caller, const SkRect& target) { 15 SkImageInfo info = SkImageInfo::MakeN32Premul(100, 100); 16 SkAutoTUnref<SkSurface> surface(caller->newSurface(info)); 17 if (nullptr == surface) { 18 surface.reset(SkSurface::NewRaster(info)); 19 } 20 SkCanvas* canvas = surface->getCanvas(); 21 // draw red everywhere, but we don't expect to see it in the draw, testing the notion 22 // that drawAtlas draws a subset-region of the atlas. 23 canvas->clear(SK_ColorRED); 24 25 SkPaint paint; 26 paint.setXfermodeMode(SkXfermode::kClear_Mode); 27 SkRect r(target); 28 r.inset(-1, -1); 29 // zero out a place (with a 1-pixel border) to land our drawing. 30 canvas->drawRect(r, paint); 31 paint.setXfermode(nullptr); 32 paint.setColor(SK_ColorBLUE); 33 paint.setAntiAlias(true); 34 canvas->drawOval(target, paint); 35 return surface->newImageSnapshot(); 36 } 37 38 SkAutoTUnref<SkImage> fAtlas; 39 40 public: DrawAtlasGM()41 DrawAtlasGM() {} 42 43 protected: 44 onShortName()45 SkString onShortName() override { 46 return SkString("draw-atlas"); 47 } 48 onISize()49 SkISize onISize() override { 50 return SkISize::Make(640, 480); 51 } 52 onDraw(SkCanvas * canvas)53 void onDraw(SkCanvas* canvas) override { 54 const SkRect target = { 50, 50, 80, 90 }; 55 if (nullptr == fAtlas) { 56 fAtlas.reset(MakeAtlas(canvas, target)); 57 } 58 59 const struct { 60 SkScalar fScale; 61 SkScalar fDegrees; 62 SkScalar fTx; 63 SkScalar fTy; 64 65 void apply(SkRSXform* xform) const { 66 const SkScalar rad = SkDegreesToRadians(fDegrees); 67 xform->fSCos = fScale * SkScalarCos(rad); 68 xform->fSSin = fScale * SkScalarSin(rad); 69 xform->fTx = fTx; 70 xform->fTy = fTy; 71 } 72 } rec[] = { 73 { 1, 0, 10, 10 }, // just translate 74 { 2, 0, 110, 10 }, // scale + translate 75 { 1, 30, 210, 10 }, // rotate + translate 76 { 2, -30, 310, 30 }, // scale + rotate + translate 77 }; 78 79 const int N = SK_ARRAY_COUNT(rec); 80 SkRSXform xform[N]; 81 SkRect tex[N]; 82 SkColor colors[N]; 83 84 for (int i = 0; i < N; ++i) { 85 rec[i].apply(&xform[i]); 86 tex[i] = target; 87 colors[i] = 0x80FF0000 + (i * 40 * 256); 88 } 89 90 SkPaint paint; 91 paint.setFilterQuality(kLow_SkFilterQuality); 92 paint.setAntiAlias(true); 93 94 canvas->drawAtlas(fAtlas, xform, tex, N, nullptr, &paint); 95 canvas->translate(0, 100); 96 canvas->drawAtlas(fAtlas, xform, tex, colors, N, SkXfermode::kSrcIn_Mode, nullptr, &paint); 97 } 98 99 private: 100 typedef GM INHERITED; 101 }; 102 DEF_GM( return new DrawAtlasGM; ) 103 104