aboutsummaryrefslogtreecommitdiffhomepage
path: root/gm/xfermodes.cpp
blob: 066ad5b695f833faacb88641906e3aeae72c96ce (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300

/*
 * Copyright 2011 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
#include "gm.h"
#include "SkBitmap.h"
#include "SkShader.h"
#include "SkXfermode.h"

namespace skiagm {

static void make_bitmaps(int w, int h, SkBitmap* src, SkBitmap* dst,
                         SkBitmap* transparent) {
    src->allocN32Pixels(w, h);
    src->eraseColor(SK_ColorTRANSPARENT);

    SkPaint p;
    p.setAntiAlias(true);

    SkRect r;
    SkScalar ww = SkIntToScalar(w);
    SkScalar hh = SkIntToScalar(h);

    {
        SkCanvas c(*src);
        p.setColor(0xFFFFCC44);
        r.set(0, 0, ww*3/4, hh*3/4);
        c.drawOval(r, p);
    }

    dst->allocN32Pixels(w, h);
    dst->eraseColor(SK_ColorTRANSPARENT);

    {
        SkCanvas c(*dst);
        p.setColor(0xFF66AAFF);
        r.set(ww/3, hh/3, ww*19/20, hh*19/20);
        c.drawRect(r, p);
    }

    transparent->allocN32Pixels(w, h);
    transparent->eraseColor(SK_ColorTRANSPARENT);
}

static uint16_t gData[] = { 0xFFFF, 0xCCCF, 0xCCCF, 0xFFFF };

class XfermodesGM : public GM {
    enum SrcType {
     //! A WxH image with a rectangle in the lower right.
     kRectangleImage_SrcType               = 0x01,
     //! kRectangleImage_SrcType with an alpha of 34.5%.
     kRectangleImageWithAlpha_SrcType      = 0x02,
     //! kRectnagleImageWithAlpha_SrcType scaled down by half.
     kSmallRectangleImageWithAlpha_SrcType = 0x04,
     //! kRectangleImage_SrcType drawn directly instead in an image.
     kRectangle_SrcType                    = 0x08,
     //! Two rectangles, first on the right half, second on the bottom half.
     kQuarterClear_SrcType                 = 0x10,
     //! kQuarterClear_SrcType in a layer.
     kQuarterClearInLayer_SrcType          = 0x20,
     //! A W/2xH/2 transparent image.
     kSmallTransparentImage_SrcType        = 0x40,
     //! kRectangleImage_SrcType drawn directly with a mask.
     kRectangleWithMask_SrcType            = 0x80,

     kAll_SrcType                          = 0xFF, //!< All the source types.
     kBasic_SrcType                        = 0x03, //!< Just basic source types.
    };

    SkBitmap    fBG;
    SkBitmap    fSrcB, fDstB, fTransparent;

    /* The srcType argument indicates what to draw for the source part. Skia
     * uses the implied shape of the drawing command and these modes
     * demonstrate that.
     */
    void draw_mode(SkCanvas* canvas, SkXfermode* mode, SrcType srcType,
                   SkScalar x, SkScalar y) {
        SkPaint p;
        SkMatrix m;
        bool restoreNeeded = false;
        m.setTranslate(x, y);

        canvas->drawBitmap(fSrcB, x, y, &p);
        p.setXfermode(mode);
        switch (srcType) {
            case kSmallTransparentImage_SrcType: {
                m.postScale(SK_ScalarHalf, SK_ScalarHalf, x, y);

                SkAutoCanvasRestore acr(canvas, true);
                canvas->concat(m);
                canvas->drawBitmap(fTransparent, 0, 0, &p);
                break;
            }
            case kQuarterClearInLayer_SrcType: {
                SkRect bounds = SkRect::MakeXYWH(x, y, SkIntToScalar(W),
                                                 SkIntToScalar(H));
                canvas->saveLayer(&bounds, &p);
                restoreNeeded = true;
                p.setXfermodeMode(SkXfermode::kSrcOver_Mode);
                // Fall through.
            }
            case kQuarterClear_SrcType: {
                SkScalar halfW = SkIntToScalar(W) / 2;
                SkScalar halfH = SkIntToScalar(H) / 2;
                p.setColor(0xFF66AAFF);
                SkRect r = SkRect::MakeXYWH(x + halfW, y, halfW,
                                            SkIntToScalar(H));
                canvas->drawRect(r, p);
                p.setColor(0xFFAA66FF);
                r = SkRect::MakeXYWH(x, y + halfH, SkIntToScalar(W), halfH);
                canvas->drawRect(r, p);
                break;
            }
            case kRectangleWithMask_SrcType: {
                canvas->save();
                restoreNeeded = true;
                SkScalar w = SkIntToScalar(W);
                SkScalar h = SkIntToScalar(H);
                SkRect r = SkRect::MakeXYWH(x, y + h / 4, w, h * 23 / 60);
                canvas->clipRect(r);
                // Fall through.
            }
            case kRectangle_SrcType: {
                SkScalar w = SkIntToScalar(W);
                SkScalar h = SkIntToScalar(H);
                SkRect r = SkRect::MakeXYWH(x + w / 3, y + h / 3,
                                            w * 37 / 60, h * 37 / 60);
                p.setColor(0xFF66AAFF);
                canvas->drawRect(r, p);
                break;
            }
            case kSmallRectangleImageWithAlpha_SrcType:
                m.postScale(SK_ScalarHalf, SK_ScalarHalf, x, y);
                // Fall through.
            case kRectangleImageWithAlpha_SrcType:
                p.setAlpha(0x88);
                // Fall through.
            case kRectangleImage_SrcType: {
                SkAutoCanvasRestore acr(canvas, true);
                canvas->concat(m);
                canvas->drawBitmap(fDstB, 0, 0, &p);
                break;
            }
            default:
                break;
        }

        if (restoreNeeded) {
            canvas->restore();
        }
    }

    void onOnceBeforeDraw() override {
        fBG.installPixels(SkImageInfo::Make(2, 2, kARGB_4444_SkColorType,
                                            kOpaque_SkAlphaType),
                          gData, 4);

        make_bitmaps(W, H, &fSrcB, &fDstB, &fTransparent);
    }

public:
    const static int W = 64;
    const static int H = 64;
    XfermodesGM() {}

protected:
    SkString onShortName() override {
        return SkString("xfermodes");
    }

    SkISize onISize() override {
        return SkISize::Make(1990, 640);
    }

    void onDraw(SkCanvas* canvas) override {
        canvas->translate(SkIntToScalar(10), SkIntToScalar(20));

        const struct {
            SkXfermode::Mode  fMode;
            const char*       fLabel;
            int               fSourceTypeMask;  // The source types to use this
                                                // mode with. See draw_mode for
                                                // an explanation of each type.
                                                // PDF has to play some tricks
                                                // to support the base modes,
                                                // test those more extensively.
        } gModes[] = {
            { SkXfermode::kClear_Mode,        "Clear",        kAll_SrcType   },
            { SkXfermode::kSrc_Mode,          "Src",          kAll_SrcType   },
            { SkXfermode::kDst_Mode,          "Dst",          kAll_SrcType   },
            { SkXfermode::kSrcOver_Mode,      "SrcOver",      kAll_SrcType   },
            { SkXfermode::kDstOver_Mode,      "DstOver",      kAll_SrcType   },
            { SkXfermode::kSrcIn_Mode,        "SrcIn",        kAll_SrcType   },
            { SkXfermode::kDstIn_Mode,        "DstIn",        kAll_SrcType   },
            { SkXfermode::kSrcOut_Mode,       "SrcOut",       kAll_SrcType   },
            { SkXfermode::kDstOut_Mode,       "DstOut",       kAll_SrcType   },
            { SkXfermode::kSrcATop_Mode,      "SrcATop",      kAll_SrcType   },
            { SkXfermode::kDstATop_Mode,      "DstATop",      kAll_SrcType   },

            { SkXfermode::kXor_Mode,          "Xor",          kBasic_SrcType },
            { SkXfermode::kPlus_Mode,         "Plus",         kBasic_SrcType },
            { SkXfermode::kModulate_Mode,     "Modulate",     kAll_SrcType   },
            { SkXfermode::kScreen_Mode,       "Screen",       kBasic_SrcType },
            { SkXfermode::kOverlay_Mode,      "Overlay",      kBasic_SrcType },
            { SkXfermode::kDarken_Mode,       "Darken",       kBasic_SrcType },
            { SkXfermode::kLighten_Mode,      "Lighten",      kBasic_SrcType },
            { SkXfermode::kColorDodge_Mode,   "ColorDodge",   kBasic_SrcType },
            { SkXfermode::kColorBurn_Mode,    "ColorBurn",    kBasic_SrcType },
            { SkXfermode::kHardLight_Mode,    "HardLight",    kBasic_SrcType },
            { SkXfermode::kSoftLight_Mode,    "SoftLight",    kBasic_SrcType },
            { SkXfermode::kDifference_Mode,   "Difference",   kBasic_SrcType },
            { SkXfermode::kExclusion_Mode,    "Exclusion",    kBasic_SrcType },
            { SkXfermode::kMultiply_Mode,     "Multiply",     kAll_SrcType   },
            { SkXfermode::kHue_Mode,          "Hue",          kBasic_SrcType },
            { SkXfermode::kSaturation_Mode,   "Saturation",   kBasic_SrcType },
            { SkXfermode::kColor_Mode,        "Color",        kBasic_SrcType },
            { SkXfermode::kLuminosity_Mode,   "Luminosity",   kBasic_SrcType },
        };

        const SkScalar w = SkIntToScalar(W);
        const SkScalar h = SkIntToScalar(H);
        SkMatrix m;
        m.setScale(SkIntToScalar(6), SkIntToScalar(6));
        SkShader* s = SkShader::CreateBitmapShader(fBG,
                                                   SkShader::kRepeat_TileMode,
                                                   SkShader::kRepeat_TileMode,
                                                   &m);

        SkPaint labelP;
        labelP.setAntiAlias(true);
        sk_tool_utils::set_portable_typeface(&labelP);
        labelP.setTextAlign(SkPaint::kCenter_Align);

        const int W = 5;

        SkScalar x0 = 0;
        SkScalar y0 = 0;
        for (int sourceType = 1; sourceType & kAll_SrcType; sourceType <<= 1) {
            SkScalar x = x0, y = y0;
            for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); i++) {
                if ((gModes[i].fSourceTypeMask & sourceType) == 0) {
                    continue;
                }
                SkXfermode* mode = SkXfermode::Create(gModes[i].fMode);
                SkAutoUnref aur(mode);
                SkRect r;
                r.set(x, y, x+w, y+h);

                SkPaint p;
                p.setStyle(SkPaint::kFill_Style);
                p.setShader(s);
                canvas->drawRect(r, p);

                canvas->saveLayer(&r, NULL);
                draw_mode(canvas, mode, static_cast<SrcType>(sourceType),
                          r.fLeft, r.fTop);
                canvas->restore();

                r.inset(-SK_ScalarHalf, -SK_ScalarHalf);
                p.setStyle(SkPaint::kStroke_Style);
                p.setShader(NULL);
                canvas->drawRect(r, p);

#if 1
                canvas->drawText(gModes[i].fLabel, strlen(gModes[i].fLabel),
                                 x + w/2, y - labelP.getTextSize()/2, labelP);
#endif
                x += w + SkIntToScalar(10);
                if ((i % W) == W - 1) {
                    x = x0;
                    y += h + SkIntToScalar(30);
                }
            }
            if (y < 320) {
                if (x > x0) {
                    y += h + SkIntToScalar(30);
                }
                y0 = y;
            } else {
                x0 += SkIntToScalar(400);
                y0 = 0;
            }
        }
        s->unref();
    }

private:
    typedef GM INHERITED;
};

//////////////////////////////////////////////////////////////////////////////

static GM* MyFactory(void*) { return new XfermodesGM; }
static GMRegistry reg(MyFactory);

}