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 10 namespace skiagm { 11 12 /** Create a bitmap image suitable for testing SkBitmap::scrollRect(). 13 * 14 * @param quarterWidth bitmap will be 4x this many pixels wide 15 * @param quarterHeight bitmap will be 4x this many pixels tall 16 * @param bitmap the bitmap data is written into this object 17 */ 18 static void make_bitmap(int quarterWidth, int quarterHeight, SkBitmap *bitmap) { 19 SkPaint pRed, pWhite, pGreen, pBlue, pLine, pAlphaGray; 20 pRed.setColor(0xFFFF9999); 21 pWhite.setColor(0xFFFFFFFF); 22 pGreen.setColor(0xFF99FF99); 23 pBlue.setColor(0xFF9999FF); 24 pLine.setColor(0xFF000000); 25 pLine.setStyle(SkPaint::kStroke_Style); 26 pAlphaGray.setColor(0x66888888); 27 28 // Prepare bitmap, and a canvas that draws into it. 29 bitmap->reset(); 30 bitmap->setConfig(SkBitmap::kARGB_8888_Config, 31 quarterWidth*4, quarterHeight*4); 32 bitmap->allocPixels(); 33 SkCanvas canvas(*bitmap); 34 35 SkScalar w = SkIntToScalar(quarterWidth); 36 SkScalar h = SkIntToScalar(quarterHeight); 37 canvas.drawRectCoords( 0, 0, w*2, h*2, pRed); 38 canvas.drawRectCoords(w*2, 0, w*4, h*2, pGreen); 39 canvas.drawRectCoords( 0, h*2, w*2, h*4, pBlue); 40 canvas.drawRectCoords(w*2, h*2, w*4, h*4, pWhite); 41 canvas.drawRectCoords(w, h, w*3, h*3, pAlphaGray); 42 canvas.drawLine(w*2, 0, w*2, h*4, pLine); 43 canvas.drawLine( 0, h*2, w*4, h*2, pLine); 44 canvas.drawRectCoords(w, h, w*3, h*3, pLine); 45 } 46 47 class BitmapScrollGM : public GM { 48 bool fInited; 49 void init() { 50 if (fInited) { 51 return; 52 } 53 fInited = true; 54 // Create the original bitmap. 55 make_bitmap(quarterWidth, quarterHeight, &origBitmap); 56 } 57 58 public: 59 BitmapScrollGM() { 60 fInited = false; 61 this->setBGColor(0xFFDDDDDD); 62 } 63 64 protected: 65 virtual SkString onShortName() { 66 return SkString("bitmapscroll"); 67 } 68 69 virtual SkISize onISize() { 70 return make_isize(800, 600); 71 } 72 73 virtual void onDraw(SkCanvas* canvas) { 74 this->init(); 75 SkIRect scrollCenterRegion = SkIRect::MakeXYWH( 76 quarterWidth, quarterHeight, quarterWidth*2+1, quarterHeight*2+1); 77 int x = quarterWidth; 78 int y = quarterHeight; 79 int xSpacing = quarterWidth * 20; 80 int ySpacing = quarterHeight * 16; 81 82 // Draw left-hand text labels. 83 drawLabel(canvas, "scroll entire bitmap", 84 x, y, x, y + ySpacing); 85 drawLabel(canvas, "scroll part of bitmap", 86 x, y + ySpacing, x, y + ySpacing*2); 87 x += 30; 88 89 // Draw various permutations of scrolled bitmaps, scrolling a bit 90 // further each time. 91 draw9(canvas, x, y, NULL, quarterWidth*1/2, quarterHeight*1/2); 92 draw9(canvas, x, y+ySpacing, &scrollCenterRegion, 93 quarterWidth*1/2, quarterHeight*1/2); 94 x += xSpacing; 95 draw9(canvas, x, y, NULL, quarterWidth*3/2, quarterHeight*3/2); 96 draw9(canvas, x, y+ySpacing, &scrollCenterRegion, 97 quarterWidth*3/2, quarterHeight*3/2); 98 x += xSpacing; 99 draw9(canvas, x, y, NULL, quarterWidth*5/2, quarterHeight*5/2); 100 draw9(canvas, x, y+ySpacing, &scrollCenterRegion, 101 quarterWidth*5/2, quarterHeight*5/2); 102 x += xSpacing; 103 draw9(canvas, x, y, NULL, quarterWidth*9/2, quarterHeight*9/2); 104 draw9(canvas, x, y+ySpacing, &scrollCenterRegion, 105 quarterWidth*9/2, quarterHeight*9/2); 106 } 107 108 void drawLabel(SkCanvas* canvas, const char *text, int startX, int startY, 109 int endX, int endY) { 110 SkPaint paint; 111 paint.setColor(0xFF000000); 112 SkPath path; 113 path.moveTo(SkIntToScalar(startX), SkIntToScalar(startY)); 114 path.lineTo(SkIntToScalar(endX), SkIntToScalar(endY)); 115 canvas->drawTextOnPath(text, strlen(text), path, NULL, paint); 116 } 117 118 /** Stamp out 9 copies of origBitmap, scrolled in each direction (and 119 * not scrolled at all). 120 */ 121 void draw9(SkCanvas* canvas, int x, int y, SkIRect* subset, 122 int scrollX, int scrollY) { 123 for (int yMult=-1; yMult<=1; yMult++) { 124 for (int xMult=-1; xMult<=1; xMult++) { 125 // Figure out the (x,y) to draw this copy at 126 SkScalar bitmapX = SkIntToScalar( 127 x + quarterWidth * 5 * (xMult+1)); 128 SkScalar bitmapY = SkIntToScalar( 129 y + quarterHeight * 5 * (yMult+1)); 130 131 // Scroll a new copy of the bitmap, and then draw it. 132 // scrollRect() should always return true, even if it's a no-op 133 SkBitmap scrolledBitmap; 134 SkDEBUGCODE(bool copyToReturnValue = )origBitmap.copyTo( 135 &scrolledBitmap, origBitmap.config()); 136 SkASSERT(copyToReturnValue); 137 SkDEBUGCODE(bool scrollRectReturnValue = )scrolledBitmap.scrollRect( 138 subset, scrollX * xMult, scrollY * yMult); 139 SkASSERT(scrollRectReturnValue); 140 canvas->drawBitmap(scrolledBitmap, bitmapX, bitmapY); 141 } 142 } 143 } 144 145 private: 146 typedef GM INHERITED; 147 static const int quarterWidth = 10; 148 static const int quarterHeight = 14; 149 SkBitmap origBitmap; 150 }; 151 152 ////////////////////////////////////////////////////////////////////////////// 153 154 static GM* MyFactory(void*) { return new BitmapScrollGM; } 155 static GMRegistry reg(MyFactory); 156 157 } 158
