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.h"
9 #include "SkBitmap.h"
10 #include "SkShader.h"
11 #include "SkXfermode.h"
12 #include "SkPM4f.h"
13 
14 #include "SkArithmeticMode.h"
15 #include "SkPixelXorXfermode.h"
16 #include "SkAvoidXfermode.h"
17 
18 #define kCustomShift    16
19 #define kCustomMask     (~0xFFFF)
20 
21 enum CustomModes {
22     kArithmetic_CustomMode  = 1 << kCustomShift,
23     kPixelXor_CustomMode    = 2 << kCustomShift,
24     kAvoid_CustomMode       = 3 << kCustomShift,
25 };
26 
make_custom(int customMode)27 static SkXfermode* make_custom(int customMode) {
28     switch (customMode) {
29         case kArithmetic_CustomMode: {
30             const SkScalar k1 = 0.25;
31             const SkScalar k2 = 0.75;
32             const SkScalar k3 = 0.75;
33             const SkScalar k4 = -0.25;
34             return SkArithmeticMode::Create(k1, k2, k3, k4);
35         }
36         case kPixelXor_CustomMode:
37             return SkPixelXorXfermode::Create(0xFF88CC44);
38         case kAvoid_CustomMode:
39             return SkAvoidXfermode::Create(0xFFFF0000, 0x44, SkAvoidXfermode::kAvoidColor_Mode);
40         default:
41             break;
42     }
43     SkASSERT(false);
44     return nullptr;
45 }
46 
47 enum SrcType {
48     //! A WxH image with a rectangle in the lower right.
49     kRectangleImage_SrcType               = 0x01,
50     //! kRectangleImage_SrcType with an alpha of 34.5%.
51     kRectangleImageWithAlpha_SrcType      = 0x02,
52     //! kRectnagleImageWithAlpha_SrcType scaled down by half.
53     kSmallRectangleImageWithAlpha_SrcType = 0x04,
54     //! kRectangleImage_SrcType drawn directly instead in an image.
55     kRectangle_SrcType                    = 0x08,
56     //! Two rectangles, first on the right half, second on the bottom half.
57     kQuarterClear_SrcType                 = 0x10,
58     //! kQuarterClear_SrcType in a layer.
59     kQuarterClearInLayer_SrcType          = 0x20,
60     //! A W/2xH/2 transparent image.
61     kSmallTransparentImage_SrcType        = 0x40,
62     //! kRectangleImage_SrcType drawn directly with a mask.
63     kRectangleWithMask_SrcType            = 0x80,
64 
65     kAll_SrcType                          = 0xFF, //!< All the source types.
66     kBasic_SrcType                        = 0x03, //!< Just basic source types.
67 };
68 
69 const struct {
70     SkXfermode::Mode  fMode;
71     const char*       fLabel;
72     int               fSourceTypeMask;  // The source types to use this
73     // mode with. See draw_mode for
74     // an explanation of each type.
75     // PDF has to play some tricks
76     // to support the base modes,
77     // test those more extensively.
78 } gModes[] = {
79     { SkXfermode::kClear_Mode,        "Clear",        kAll_SrcType   },
80     { SkXfermode::kSrc_Mode,          "Src",          kAll_SrcType   },
81     { SkXfermode::kDst_Mode,          "Dst",          kAll_SrcType   },
82     { SkXfermode::kSrcOver_Mode,      "SrcOver",      kAll_SrcType   },
83     { SkXfermode::kDstOver_Mode,      "DstOver",      kAll_SrcType   },
84     { SkXfermode::kSrcIn_Mode,        "SrcIn",        kAll_SrcType   },
85     { SkXfermode::kDstIn_Mode,        "DstIn",        kAll_SrcType   },
86     { SkXfermode::kSrcOut_Mode,       "SrcOut",       kAll_SrcType   },
87     { SkXfermode::kDstOut_Mode,       "DstOut",       kAll_SrcType   },
88     { SkXfermode::kSrcATop_Mode,      "SrcATop",      kAll_SrcType   },
89     { SkXfermode::kDstATop_Mode,      "DstATop",      kAll_SrcType   },
90 
91     { SkXfermode::kXor_Mode,          "Xor",          kBasic_SrcType },
92     { SkXfermode::kPlus_Mode,         "Plus",         kBasic_SrcType },
93     { SkXfermode::kModulate_Mode,     "Modulate",     kAll_SrcType   },
94     { SkXfermode::kScreen_Mode,       "Screen",       kBasic_SrcType },
95     { SkXfermode::kOverlay_Mode,      "Overlay",      kBasic_SrcType },
96     { SkXfermode::kDarken_Mode,       "Darken",       kBasic_SrcType },
97     { SkXfermode::kLighten_Mode,      "Lighten",      kBasic_SrcType },
98     { SkXfermode::kColorDodge_Mode,   "ColorDodge",   kBasic_SrcType },
99     { SkXfermode::kColorBurn_Mode,    "ColorBurn",    kBasic_SrcType },
100     { SkXfermode::kHardLight_Mode,    "HardLight",    kBasic_SrcType },
101     { SkXfermode::kSoftLight_Mode,    "SoftLight",    kBasic_SrcType },
102     { SkXfermode::kDifference_Mode,   "Difference",   kBasic_SrcType },
103     { SkXfermode::kExclusion_Mode,    "Exclusion",    kBasic_SrcType },
104     { SkXfermode::kMultiply_Mode,     "Multiply",     kAll_SrcType   },
105     { SkXfermode::kHue_Mode,          "Hue",          kBasic_SrcType },
106     { SkXfermode::kSaturation_Mode,   "Saturation",   kBasic_SrcType },
107     { SkXfermode::kColor_Mode,        "Color",        kBasic_SrcType },
108     { SkXfermode::kLuminosity_Mode,   "Luminosity",   kBasic_SrcType },
109 
110     { SkXfermode::Mode(0xFFFF),       "Arithmetic",   kBasic_SrcType + kArithmetic_CustomMode   },
111     { SkXfermode::Mode(0xFFFF),       "PixelXor",     kBasic_SrcType + kPixelXor_CustomMode     },
112     { SkXfermode::Mode(0xFFFF),       "Avoid",        kBasic_SrcType + kAvoid_CustomMode        },
113 };
114 
make_bitmaps(int w,int h,SkBitmap * src,SkBitmap * dst,SkBitmap * transparent)115 static void make_bitmaps(int w, int h, SkBitmap* src, SkBitmap* dst,
116                          SkBitmap* transparent) {
117     src->allocN32Pixels(w, h);
118     src->eraseColor(SK_ColorTRANSPARENT);
119 
120     SkPaint p;
121     p.setAntiAlias(true);
122 
123     SkRect r;
124     SkScalar ww = SkIntToScalar(w);
125     SkScalar hh = SkIntToScalar(h);
126 
127     {
128         SkCanvas c(*src);
129         p.setColor(sk_tool_utils::color_to_565(0xFFFFCC44));
130         r.set(0, 0, ww*3/4, hh*3/4);
131         c.drawOval(r, p);
132     }
133 
134     dst->allocN32Pixels(w, h);
135     dst->eraseColor(SK_ColorTRANSPARENT);
136 
137     {
138         SkCanvas c(*dst);
139         p.setColor(sk_tool_utils::color_to_565(0xFF66AAFF));
140         r.set(ww/3, hh/3, ww*19/20, hh*19/20);
141         c.drawRect(r, p);
142     }
143 
144     transparent->allocN32Pixels(w, h);
145     transparent->eraseColor(SK_ColorTRANSPARENT);
146 }
147 
148 static uint16_t gData[] = { 0xFFFF, 0xCCCF, 0xCCCF, 0xFFFF };
149 
150 class XfermodesGM : public skiagm::GM {
151     SkBitmap    fBG;
152     SkBitmap    fSrcB, fDstB, fTransparent;
153 
154     /* The srcType argument indicates what to draw for the source part. Skia
155      * uses the implied shape of the drawing command and these modes
156      * demonstrate that.
157      */
draw_mode(SkCanvas * canvas,SkXfermode * mode,SrcType srcType,SkScalar x,SkScalar y)158     void draw_mode(SkCanvas* canvas, SkXfermode* mode, SrcType srcType,
159                    SkScalar x, SkScalar y) {
160         SkPaint p;
161         SkMatrix m;
162         bool restoreNeeded = false;
163         m.setTranslate(x, y);
164 
165         canvas->drawBitmap(fSrcB, x, y, &p);
166         p.setXfermode(mode);
167         switch (srcType) {
168             case kSmallTransparentImage_SrcType: {
169                 m.postScale(SK_ScalarHalf, SK_ScalarHalf, x, y);
170 
171                 SkAutoCanvasRestore acr(canvas, true);
172                 canvas->concat(m);
173                 canvas->drawBitmap(fTransparent, 0, 0, &p);
174                 break;
175             }
176             case kQuarterClearInLayer_SrcType: {
177                 SkRect bounds = SkRect::MakeXYWH(x, y, SkIntToScalar(W),
178                                                  SkIntToScalar(H));
179                 canvas->saveLayer(&bounds, &p);
180                 restoreNeeded = true;
181                 p.setXfermodeMode(SkXfermode::kSrcOver_Mode);
182                 // Fall through.
183             }
184             case kQuarterClear_SrcType: {
185                 SkScalar halfW = SkIntToScalar(W) / 2;
186                 SkScalar halfH = SkIntToScalar(H) / 2;
187                 p.setColor(sk_tool_utils::color_to_565(0xFF66AAFF));
188                 SkRect r = SkRect::MakeXYWH(x + halfW, y, halfW,
189                                             SkIntToScalar(H));
190                 canvas->drawRect(r, p);
191                 p.setColor(sk_tool_utils::color_to_565(0xFFAA66FF));
192                 r = SkRect::MakeXYWH(x, y + halfH, SkIntToScalar(W), halfH);
193                 canvas->drawRect(r, p);
194                 break;
195             }
196             case kRectangleWithMask_SrcType: {
197                 canvas->save();
198                 restoreNeeded = true;
199                 SkScalar w = SkIntToScalar(W);
200                 SkScalar h = SkIntToScalar(H);
201                 SkRect r = SkRect::MakeXYWH(x, y + h / 4, w, h * 23 / 60);
202                 canvas->clipRect(r);
203                 // Fall through.
204             }
205             case kRectangle_SrcType: {
206                 SkScalar w = SkIntToScalar(W);
207                 SkScalar h = SkIntToScalar(H);
208                 SkRect r = SkRect::MakeXYWH(x + w / 3, y + h / 3,
209                                             w * 37 / 60, h * 37 / 60);
210                 p.setColor(sk_tool_utils::color_to_565(0xFF66AAFF));
211                 canvas->drawRect(r, p);
212                 break;
213             }
214             case kSmallRectangleImageWithAlpha_SrcType:
215                 m.postScale(SK_ScalarHalf, SK_ScalarHalf, x, y);
216                 // Fall through.
217             case kRectangleImageWithAlpha_SrcType:
218                 p.setAlpha(0x88);
219                 // Fall through.
220             case kRectangleImage_SrcType: {
221                 SkAutoCanvasRestore acr(canvas, true);
222                 canvas->concat(m);
223                 canvas->drawBitmap(fDstB, 0, 0, &p);
224                 break;
225             }
226             default:
227                 break;
228         }
229 
230         if (restoreNeeded) {
231             canvas->restore();
232         }
233     }
234 
onOnceBeforeDraw()235     void onOnceBeforeDraw() override {
236         fBG.installPixels(SkImageInfo::Make(2, 2, kARGB_4444_SkColorType,
237                                             kOpaque_SkAlphaType),
238                           gData, 4);
239 
240         make_bitmaps(W, H, &fSrcB, &fDstB, &fTransparent);
241     }
242 
243 public:
244     const static int W = 64;
245     const static int H = 64;
XfermodesGM()246     XfermodesGM() {}
247 
248 protected:
onShortName()249     SkString onShortName() override {
250         return SkString("xfermodes");
251     }
252 
onISize()253     SkISize onISize() override {
254         return SkISize::Make(1990, 660);
255     }
256 
onDraw(SkCanvas * canvas)257     void onDraw(SkCanvas* canvas) override {
258         canvas->translate(SkIntToScalar(10), SkIntToScalar(20));
259 
260         const SkScalar w = SkIntToScalar(W);
261         const SkScalar h = SkIntToScalar(H);
262         SkMatrix m;
263         m.setScale(SkIntToScalar(6), SkIntToScalar(6));
264         SkShader* s = SkShader::CreateBitmapShader(fBG,
265                                                    SkShader::kRepeat_TileMode,
266                                                    SkShader::kRepeat_TileMode,
267                                                    &m);
268 
269         SkPaint labelP;
270         labelP.setAntiAlias(true);
271         sk_tool_utils::set_portable_typeface(&labelP);
272         labelP.setTextAlign(SkPaint::kCenter_Align);
273 
274         const int W = 5;
275 
276         SkScalar x0 = 0;
277         SkScalar y0 = 0;
278         for (int sourceType = 1; sourceType & kAll_SrcType; sourceType <<= 1) {
279             SkScalar x = x0, y = y0;
280             for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); i++) {
281                 if ((gModes[i].fSourceTypeMask & sourceType) == 0) {
282                     continue;
283                 }
284                 SkAutoTUnref<SkXfermode> mode;
285                 if (gModes[i].fSourceTypeMask & kCustomMask) {
286                     mode.reset(make_custom(gModes[i].fSourceTypeMask & kCustomMask));
287                 } else {
288                     mode.reset(SkXfermode::Create(gModes[i].fMode));
289                 }
290                 SkRect r;
291                 r.set(x, y, x+w, y+h);
292 
293                 SkPaint p;
294                 p.setStyle(SkPaint::kFill_Style);
295                 p.setShader(s);
296                 canvas->drawRect(r, p);
297 
298                 canvas->saveLayer(&r, nullptr);
299                 draw_mode(canvas, mode, static_cast<SrcType>(sourceType),
300                           r.fLeft, r.fTop);
301                 canvas->restore();
302 
303                 r.inset(-SK_ScalarHalf, -SK_ScalarHalf);
304                 p.setStyle(SkPaint::kStroke_Style);
305                 p.setShader(nullptr);
306                 canvas->drawRect(r, p);
307 
308 #if 1
309                 canvas->drawText(gModes[i].fLabel, strlen(gModes[i].fLabel),
310                                  x + w/2, y - labelP.getTextSize()/2, labelP);
311 #endif
312                 x += w + SkIntToScalar(10);
313                 if ((i % W) == W - 1) {
314                     x = x0;
315                     y += h + SkIntToScalar(30);
316                 }
317             }
318             if (y < 320) {
319                 if (x > x0) {
320                     y += h + SkIntToScalar(30);
321                 }
322                 y0 = y;
323             } else {
324                 x0 += SkIntToScalar(400);
325                 y0 = 0;
326             }
327         }
328         s->unref();
329     }
330 
331 private:
332     typedef GM INHERITED;
333 };
334 DEF_GM( return new XfermodesGM; )
335