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 */
make_bitmap(int quarterWidth,int quarterHeight,SkBitmap * bitmap)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->allocN32Pixels(quarterWidth*4, quarterHeight*4);
30 SkCanvas canvas(*bitmap);
31
32 SkScalar w = SkIntToScalar(quarterWidth);
33 SkScalar h = SkIntToScalar(quarterHeight);
34 canvas.drawRectCoords( 0, 0, w*2, h*2, pRed);
35 canvas.drawRectCoords(w*2, 0, w*4, h*2, pGreen);
36 canvas.drawRectCoords( 0, h*2, w*2, h*4, pBlue);
37 canvas.drawRectCoords(w*2, h*2, w*4, h*4, pWhite);
38 canvas.drawRectCoords(w, h, w*3, h*3, pAlphaGray);
39 canvas.drawLine(w*2, 0, w*2, h*4, pLine);
40 canvas.drawLine( 0, h*2, w*4, h*2, pLine);
41 canvas.drawRectCoords(w, h, w*3, h*3, pLine);
42 }
43
44 class BitmapScrollGM : public GM {
45 bool fInited;
init()46 void init() {
47 if (fInited) {
48 return;
49 }
50 fInited = true;
51 // Create the original bitmap.
52 make_bitmap(quarterWidth, quarterHeight, &origBitmap);
53 }
54
55 public:
BitmapScrollGM()56 BitmapScrollGM() {
57 fInited = false;
58 this->setBGColor(0xFFDDDDDD);
59 }
60
61 protected:
onGetFlags() const62 virtual uint32_t onGetFlags() const SK_OVERRIDE {
63 return kSkipTiled_Flag;
64 }
65
onShortName()66 virtual SkString onShortName() {
67 return SkString("bitmapscroll");
68 }
69
onISize()70 virtual SkISize onISize() {
71 return SkISize::Make(800, 600);
72 }
73
onDraw(SkCanvas * canvas)74 virtual void onDraw(SkCanvas* canvas) {
75 this->init();
76 SkIRect scrollCenterRegion = SkIRect::MakeXYWH(
77 quarterWidth, quarterHeight, quarterWidth*2+1, quarterHeight*2+1);
78 int x = quarterWidth;
79 int y = quarterHeight;
80 int xSpacing = quarterWidth * 20;
81 int ySpacing = quarterHeight * 16;
82
83 // Draw left-hand text labels.
84 drawLabel(canvas, "scroll entire bitmap",
85 x, y, x, y + ySpacing);
86 drawLabel(canvas, "scroll part of bitmap",
87 x, y + ySpacing, x, y + ySpacing*2);
88 x += 30;
89
90 // Draw various permutations of scrolled bitmaps, scrolling a bit
91 // further each time.
92 draw9(canvas, x, y, NULL, quarterWidth*1/2, quarterHeight*1/2);
93 draw9(canvas, x, y+ySpacing, &scrollCenterRegion,
94 quarterWidth*1/2, quarterHeight*1/2);
95 x += xSpacing;
96 draw9(canvas, x, y, NULL, quarterWidth*3/2, quarterHeight*3/2);
97 draw9(canvas, x, y+ySpacing, &scrollCenterRegion,
98 quarterWidth*3/2, quarterHeight*3/2);
99 x += xSpacing;
100 draw9(canvas, x, y, NULL, quarterWidth*5/2, quarterHeight*5/2);
101 draw9(canvas, x, y+ySpacing, &scrollCenterRegion,
102 quarterWidth*5/2, quarterHeight*5/2);
103 x += xSpacing;
104 draw9(canvas, x, y, NULL, quarterWidth*9/2, quarterHeight*9/2);
105 draw9(canvas, x, y+ySpacing, &scrollCenterRegion,
106 quarterWidth*9/2, quarterHeight*9/2);
107 }
108
drawLabel(SkCanvas * canvas,const char * text,int startX,int startY,int endX,int endY)109 void drawLabel(SkCanvas* canvas, const char *text, int startX, int startY,
110 int endX, int endY) {
111 SkPaint paint;
112 paint.setColor(0xFF000000);
113 SkPath path;
114 path.moveTo(SkIntToScalar(startX), SkIntToScalar(startY));
115 path.lineTo(SkIntToScalar(endX), SkIntToScalar(endY));
116 canvas->drawTextOnPath(text, strlen(text), path, NULL, paint);
117 }
118
119 /** Stamp out 9 copies of origBitmap, scrolled in each direction (and
120 * not scrolled at all).
121 */
draw9(SkCanvas * canvas,int x,int y,SkIRect * subset,int scrollX,int scrollY)122 void draw9(SkCanvas* canvas, int x, int y, SkIRect* subset,
123 int scrollX, int scrollY) {
124 for (int yMult=-1; yMult<=1; yMult++) {
125 for (int xMult=-1; xMult<=1; xMult++) {
126 // Figure out the (x,y) to draw this copy at
127 SkScalar bitmapX = SkIntToScalar(
128 x + quarterWidth * 5 * (xMult+1));
129 SkScalar bitmapY = SkIntToScalar(
130 y + quarterHeight * 5 * (yMult+1));
131
132 // Scroll a new copy of the bitmap, and then draw it.
133 // scrollRect() should always return true, even if it's a no-op
134 SkBitmap scrolledBitmap;
135 SkDEBUGCODE(bool copyToReturnValue = )origBitmap.copyTo(
136 &scrolledBitmap, origBitmap.colorType());
137 SkASSERT(copyToReturnValue);
138 SkDEBUGCODE(bool scrollRectReturnValue = )scrolledBitmap.scrollRect(
139 subset, scrollX * xMult, scrollY * yMult);
140 SkASSERT(scrollRectReturnValue);
141 canvas->drawBitmap(scrolledBitmap, bitmapX, bitmapY);
142 }
143 }
144 }
145
146 private:
147 typedef GM INHERITED;
148 static const int quarterWidth = 10;
149 static const int quarterHeight = 14;
150 SkBitmap origBitmap;
151 };
152
153 //////////////////////////////////////////////////////////////////////////////
154
MyFactory(void *)155 static GM* MyFactory(void*) { return new BitmapScrollGM; }
156 static GMRegistry reg(MyFactory);
157
158 }
159