1/*
2 * Copyright 2014 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 "sk_tool_utils.h"
10
11#include "SkCanvas.h"
12#include "SkGradientShader.h"
13#include "SkPoint.h"
14#include "SkShader.h"
15#include "SkTextBlob.h"
16#include "SkTDArray.h"
17#include "SkTypeface.h"
18
19// This GM exercises drawTextBlob offset vs. shader space behavior.
20class TextBlobShaderGM : public skiagm::GM {
21public:
22    TextBlobShaderGM(const char* txt) {
23        SkPaint p;
24        sk_tool_utils::set_portable_typeface(&p);
25        size_t txtLen = strlen(txt);
26        fGlyphs.append(p.textToGlyphs(txt, txtLen, nullptr));
27        p.textToGlyphs(txt, txtLen, fGlyphs.begin());
28    }
29
30protected:
31
32    void onOnceBeforeDraw() override {
33        SkPaint p;
34        p.setAntiAlias(true);
35        p.setSubpixelText(true);
36        p.setTextSize(30);
37        p.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
38        sk_tool_utils::set_portable_typeface(&p);
39
40        SkTextBlobBuilder builder;
41        int glyphCount = fGlyphs.count();
42        const SkTextBlobBuilder::RunBuffer* run;
43
44        run = &builder.allocRun(p, glyphCount, 10, 10, nullptr);
45        memcpy(run->glyphs, fGlyphs.begin(), glyphCount * sizeof(uint16_t));
46
47        run = &builder.allocRunPosH(p, glyphCount,  80, nullptr);
48        memcpy(run->glyphs, fGlyphs.begin(), glyphCount * sizeof(uint16_t));
49        for (int i = 0; i < glyphCount; ++i) {
50            run->pos[i] = p.getTextSize() * i * .75f;
51        }
52
53        run = &builder.allocRunPos(p, glyphCount, nullptr);
54        memcpy(run->glyphs, fGlyphs.begin(), glyphCount * sizeof(uint16_t));
55        for (int i = 0; i < glyphCount; ++i) {
56            run->pos[i * 2] = p.getTextSize() * i * .75f;
57            run->pos[i * 2 + 1] = 150 + 5 * sinf((float)i * 8 / glyphCount);
58        }
59
60        fBlob = builder.make();
61
62        SkColor  colors[2];
63        colors[0] = SK_ColorRED;
64        colors[1] = SK_ColorGREEN;
65
66        SkScalar pos[SK_ARRAY_COUNT(colors)];
67        for (unsigned i = 0; i < SK_ARRAY_COUNT(pos); ++i) {
68            pos[i] = (float)i / (SK_ARRAY_COUNT(pos) - 1);
69        }
70
71        SkISize sz = this->onISize();
72        fShader = SkGradientShader::MakeRadial(SkPoint::Make(SkIntToScalar(sz.width() / 2),
73                                               SkIntToScalar(sz.height() / 2)),
74                                               sz.width() * .66f, colors, pos,
75                                               SK_ARRAY_COUNT(colors),
76                                               SkShader::kRepeat_TileMode);
77    }
78
79    SkString onShortName() override {
80        return SkString("textblobshader");
81    }
82
83    SkISize onISize() override {
84        return SkISize::Make(640, 480);
85    }
86
87    void onDraw(SkCanvas* canvas) override {
88        SkPaint p;
89        p.setStyle(SkPaint::kFill_Style);
90        p.setShader(fShader);
91
92        SkISize sz = this->onISize();
93        constexpr int kXCount = 4;
94        constexpr int kYCount = 3;
95        for (int i = 0; i < kXCount; ++i) {
96            for (int j = 0; j < kYCount; ++j) {
97                canvas->drawTextBlob(fBlob,
98                                     SkIntToScalar(i * sz.width() / kXCount),
99                                     SkIntToScalar(j * sz.height() / kYCount),
100                                     p);
101            }
102        }
103    }
104
105private:
106    SkTDArray<uint16_t> fGlyphs;
107    sk_sp<SkTextBlob>   fBlob;
108    sk_sp<SkShader>     fShader;
109
110    typedef skiagm::GM INHERITED;
111};
112
113DEF_GM(return new TextBlobShaderGM("Blobber");)
114