1 /*
2 * Copyright 2017 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
10 #if SK_SUPPORT_ATLAS_TEXT
11 #include "GrContext.h"
12
13 #include "SkAtlasTextContext.h"
14 #include "SkAtlasTextFont.h"
15 #include "SkAtlasTextTarget.h"
16 #include "SkBitmap.h"
17 #include "SkCanvas.h"
18 #include "SkFont.h"
19 #include "SkTypeface.h"
20 #include "SkUTF.h"
21 #include "gpu/TestContext.h"
22 #include "gpu/atlastext/GLTestAtlasTextRenderer.h"
23 #include "gpu/atlastext/TestAtlasTextRenderer.h"
24 #include "sk_tool_utils.h"
25
26 // GM that draws text using the Atlas Text interface offscreen and then blits that to the canvas.
27
draw_string(SkAtlasTextTarget * target,const SkString & text,SkScalar x,SkScalar y,uint32_t color,sk_sp<SkTypeface> typeface,float size)28 static SkScalar draw_string(SkAtlasTextTarget* target, const SkString& text, SkScalar x, SkScalar y,
29 uint32_t color, sk_sp<SkTypeface> typeface, float size) {
30 if (!text.size()) {
31 return x;
32 }
33 auto atlas_font = SkAtlasTextFont::Make(typeface, size);
34 int cnt = SkUTF::CountUTF8(text.c_str(), text.size());
35 std::unique_ptr<SkGlyphID[]> glyphs(new SkGlyphID[cnt]);
36 typeface->charsToGlyphs(text.c_str(), SkTypeface::Encoding::kUTF8_Encoding, glyphs.get(), cnt);
37
38 // Using a paint to get the positions for each glyph.
39 SkFont font;
40 font.setSize(size);
41 font.setTypeface(std::move(typeface));
42 std::unique_ptr<SkScalar[]> widths(new SkScalar[cnt]);
43 font.getWidths(glyphs.get(), cnt, widths.get());
44
45 std::unique_ptr<SkPoint[]> positions(new SkPoint[cnt]);
46 positions[0] = {x, y};
47 for (int i = 1; i < cnt; ++i) {
48 positions[i] = {positions[i - 1].fX + widths[i - 1], y};
49 }
50
51 target->drawText(glyphs.get(), positions.get(), cnt, color, *atlas_font);
52
53 // Return the width of the of draw.
54 return positions[cnt - 1].fX + widths[cnt - 1] - positions[0].fX;
55 }
56
57 class AtlasTextGM : public skiagm::GM {
58 public:
59 AtlasTextGM() = default;
60
61 protected:
onShortName()62 SkString onShortName() override { return SkString("atlastext"); }
63
onISize()64 SkISize onISize() override { return SkISize::Make(kSize, kSize); }
65
onOnceBeforeDraw()66 void onOnceBeforeDraw() override {
67 fRenderer = sk_gpu_test::MakeGLTestAtlasTextRenderer();
68 if (!fRenderer) {
69 return;
70 }
71 fContext = SkAtlasTextContext::Make(fRenderer);
72 auto targetHandle = fRenderer->makeTargetHandle(kSize, kSize);
73 if (!targetHandle) {
74 return;
75 }
76
77 fTarget = SkAtlasTextTarget::Make(fContext, kSize, kSize, targetHandle);
78
79 fTypefaces[0] = sk_tool_utils::create_portable_typeface("serif", SkFontStyle::Italic());
80 fTypefaces[1] =
81 sk_tool_utils::create_portable_typeface("sans-serif", SkFontStyle::Italic());
82 fTypefaces[2] = sk_tool_utils::create_portable_typeface("serif", SkFontStyle::Normal());
83 fTypefaces[3] =
84 sk_tool_utils::create_portable_typeface("sans-serif", SkFontStyle::Normal());
85 fTypefaces[4] = sk_tool_utils::create_portable_typeface("serif", SkFontStyle::Bold());
86 fTypefaces[5] = sk_tool_utils::create_portable_typeface("sans-serif", SkFontStyle::Bold());
87 }
88
onDraw(SkCanvas * canvas,SkString * errorMsg)89 DrawResult onDraw(SkCanvas* canvas, SkString* errorMsg) override {
90 if (!fRenderer || !fTarget || !fTarget->handle()) {
91 *errorMsg = "No renderer and/or target.";
92 return DrawResult::kFail;
93 }
94 fRenderer->clearTarget(fTarget->handle(), 0xFF808080);
95 auto bmp = this->drawText();
96 SkPaint paint;
97 paint.setBlendMode(SkBlendMode::kSrc);
98 canvas->drawBitmap(bmp, 0, 0);
99 return DrawResult::kOk;
100 }
101
102 private:
drawText()103 SkBitmap drawText() {
104 static const int kSizes[] = {8, 13, 18, 23, 30};
105
106 static const SkString kTexts[] = {SkString("ABCDEFGHIJKLMNOPQRSTUVWXYZ"),
107 SkString("abcdefghijklmnopqrstuvwxyz"),
108 SkString("0123456789"),
109 SkString("!@#$%^&*()<>[]{}")};
110 SkScalar x = 0;
111 SkScalar y = 10;
112
113 SkRandom random;
114 do {
115 for (auto s : kSizes) {
116 auto size = 2 * s;
117 for (const auto& typeface : fTypefaces) {
118 for (const auto& text : kTexts) {
119 // Choose a random color but don't let alpha be too small to see.
120 uint32_t color = random.nextU() | 0x40000000;
121 fTarget->save();
122 // Randomly add a little bit of perspective
123 if (random.nextBool()) {
124 SkMatrix persp;
125 persp.reset();
126 persp.setPerspY(0.0005f);
127 persp.preTranslate(-x, -y + s);
128 persp.postTranslate(x, y - s);
129 fTarget->concat(persp);
130 }
131 // Randomly switch between positioning with a matrix vs x, y passed to draw.
132 SkScalar drawX = x, drawY = y;
133 if (random.nextBool()) {
134 fTarget->translate(x, y);
135 drawX = drawY = 0;
136 }
137 x += size +
138 draw_string(fTarget.get(), text, drawX, drawY, color, typeface, size);
139 x = SkScalarCeilToScalar(x);
140 fTarget->restore();
141 // Flush periodically to test continued drawing after a flush.
142 if ((random.nextU() % 8) == 0) {
143 fTarget->flush();
144 }
145 if (x + 100 > kSize) {
146 x = 0;
147 y += SkScalarCeilToScalar(size + 3);
148 if (y > kSize) {
149 fTarget->flush();
150 return fRenderer->readTargetHandle(fTarget->handle());
151 }
152 }
153 }
154 }
155 }
156 } while (true);
157 }
158
159 static constexpr int kSize = 1280;
160
161 sk_sp<SkTypeface> fTypefaces[6];
162 sk_sp<sk_gpu_test::TestAtlasTextRenderer> fRenderer;
163 std::unique_ptr<SkAtlasTextTarget> fTarget;
164 sk_sp<SkAtlasTextContext> fContext;
165
166 typedef GM INHERITED;
167 };
168
169 constexpr int AtlasTextGM::kSize;
170
171 //////////////////////////////////////////////////////////////////////////////
172
173 DEF_GM(return new AtlasTextGM;)
174
175 #endif
176