1 /*
2 * Copyright 2022 Google LLC
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 "src/gpu/graphite/render/BitmapTextRenderStep.h"
9
10 #include "include/core/SkM44.h"
11 #include "include/core/SkRefCnt.h"
12 #include "include/core/SkSamplingOptions.h"
13 #include "include/core/SkSize.h"
14 #include "include/core/SkTileMode.h"
15 #include "include/gpu/graphite/Recorder.h"
16 #include "include/private/base/SkAssert.h"
17 #include "include/private/base/SkDebug.h"
18 #include "src/core/SkSLTypeShared.h"
19 #include "src/gpu/AtlasTypes.h"
20 #include "src/gpu/graphite/AtlasProvider.h"
21 #include "src/gpu/graphite/Attribute.h"
22 #include "src/gpu/graphite/ContextUtils.h"
23 #include "src/gpu/graphite/DrawOrder.h"
24 #include "src/gpu/graphite/DrawParams.h"
25 #include "src/gpu/graphite/DrawTypes.h"
26 #include "src/gpu/graphite/PipelineData.h"
27 #include "src/gpu/graphite/RecorderPriv.h"
28 #include "src/gpu/graphite/TextureProxy.h"
29 #include "src/gpu/graphite/geom/Geometry.h"
30 #include "src/gpu/graphite/geom/SubRunData.h"
31 #include "src/gpu/graphite/geom/Transform_graphite.h"
32 #include "src/gpu/graphite/render/CommonDepthStencilSettings.h"
33 #include "src/gpu/graphite/text/TextAtlasManager.h"
34 #include "src/sksl/SkSLString.h"
35 #include "src/text/gpu/SubRunContainer.h"
36 #include "src/text/gpu/VertexFiller.h"
37
38 #include <string_view>
39
40 using AtlasSubRun = sktext::gpu::AtlasSubRun;
41
42 namespace skgpu::graphite {
43
44 namespace {
45
46 // We are expecting to sample from up to 4 textures
47 constexpr int kNumTextAtlasTextures = 4;
48
variant_name(skgpu::MaskFormat variant)49 std::string variant_name(skgpu::MaskFormat variant) {
50 switch (variant) {
51 case skgpu::MaskFormat::kA8:
52 return "mask";
53 case skgpu::MaskFormat::kA565:
54 return "LCD";
55 case skgpu::MaskFormat::kARGB:
56 return "color";
57 default:
58 SkUNREACHABLE;
59 }
60 }
61
62 } // namespace
63
BitmapTextRenderStep(skgpu::MaskFormat variant)64 BitmapTextRenderStep::BitmapTextRenderStep(skgpu::MaskFormat variant)
65 : RenderStep("BitmapTextRenderStep",
66 variant_name(variant),
67 Flags(variant),
68 /*uniforms=*/{{"subRunDeviceMatrix", SkSLType::kFloat4x4},
69 {"deviceToLocal" , SkSLType::kFloat4x4},
70 {"atlasSizeInv" , SkSLType::kFloat2}},
71 PrimitiveType::kTriangleStrip,
72 kDirectDepthGEqualPass,
73 /*vertexAttrs=*/ {},
74 /*instanceAttrs=*/
75 {{"size", VertexAttribType::kUShort2, SkSLType::kUShort2},
76 {"uvPos", VertexAttribType::kUShort2, SkSLType::kUShort2},
77 {"xyPos", VertexAttribType::kFloat2, SkSLType::kFloat2},
78 {"indexAndFlags", VertexAttribType::kUShort2, SkSLType::kUShort2},
79 {"strikeToSourceScale", VertexAttribType::kFloat, SkSLType::kFloat},
80 {"depth", VertexAttribType::kFloat, SkSLType::kFloat},
81 {"ssboIndices", VertexAttribType::kUInt2, SkSLType::kUInt2}},
82 /*varyings=*/
83 {{"textureCoords", SkSLType::kFloat2},
84 {"texIndex", SkSLType::kHalf},
85 {"maskFormat", SkSLType::kHalf}}) {}
86
~BitmapTextRenderStep()87 BitmapTextRenderStep::~BitmapTextRenderStep() {}
88
Flags(skgpu::MaskFormat variant)89 SkEnumBitMask<RenderStep::Flags> BitmapTextRenderStep::Flags(skgpu::MaskFormat variant) {
90 switch (variant) {
91 case skgpu::MaskFormat::kA8:
92 return Flags::kPerformsShading | Flags::kHasTextures | Flags::kEmitsCoverage;
93 case skgpu::MaskFormat::kA565:
94 return Flags::kPerformsShading | Flags::kHasTextures | Flags::kEmitsCoverage |
95 Flags::kLCDCoverage;
96 case skgpu::MaskFormat::kARGB:
97 return Flags::kPerformsShading | Flags::kHasTextures | Flags::kEmitsPrimitiveColor;
98 default:
99 SkUNREACHABLE;
100 }
101 }
102
vertexSkSL() const103 std::string BitmapTextRenderStep::vertexSkSL() const {
104 // Returns the body of a vertex function, which must define a float4 devPosition variable and
105 // must write to an already-defined float2 stepLocalCoords variable.
106 return "texIndex = half(indexAndFlags.x);"
107 "maskFormat = half(indexAndFlags.y);"
108 "float2 unormTexCoords;"
109 "float4 devPosition = text_vertex_fn(float2(sk_VertexID >> 1, sk_VertexID & 1), "
110 "subRunDeviceMatrix, "
111 "deviceToLocal, "
112 "atlasSizeInv, "
113 "float2(size), "
114 "float2(uvPos), "
115 "xyPos, "
116 "strikeToSourceScale, "
117 "depth, "
118 "textureCoords, "
119 "unormTexCoords, "
120 "stepLocalCoords);";
121 }
122
texturesAndSamplersSkSL(const ResourceBindingRequirements & bindingReqs,int * nextBindingIndex) const123 std::string BitmapTextRenderStep::texturesAndSamplersSkSL(
124 const ResourceBindingRequirements& bindingReqs, int* nextBindingIndex) const {
125 std::string result;
126
127 for (unsigned int i = 0; i < kNumTextAtlasTextures; ++i) {
128 result += EmitSamplerLayout(bindingReqs, nextBindingIndex);
129 SkSL::String::appendf(&result, " sampler2D text_atlas_%u;\n", i);
130 }
131
132 return result;
133 }
134
135
fragmentColorSkSL() const136 const char* BitmapTextRenderStep::fragmentColorSkSL() const {
137 // The returned SkSL must write its color into a 'half4 primitiveColor' variable
138 // (defined in the calling code).
139 static_assert(kNumTextAtlasTextures == 4);
140 return "primitiveColor = sample_indexed_atlas(textureCoords, "
141 "int(texIndex), "
142 "text_atlas_0, "
143 "text_atlas_1, "
144 "text_atlas_2, "
145 "text_atlas_3);";
146 }
147
fragmentCoverageSkSL() const148 const char* BitmapTextRenderStep::fragmentCoverageSkSL() const {
149 // The returned SkSL must write its coverage into a 'half4 outputCoverage' variable (defined in
150 // the calling code) with the actual coverage splatted out into all four channels.
151 static_assert(kNumTextAtlasTextures == 4);
152 return "outputCoverage = bitmap_text_coverage_fn(sample_indexed_atlas(textureCoords, "
153 "int(texIndex), "
154 "text_atlas_0, "
155 "text_atlas_1, "
156 "text_atlas_2, "
157 "text_atlas_3), "
158 "int(maskFormat));";
159 }
160
writeVertices(DrawWriter * dw,const DrawParams & params,skvx::uint2 ssboIndices) const161 void BitmapTextRenderStep::writeVertices(DrawWriter* dw,
162 const DrawParams& params,
163 skvx::uint2 ssboIndices) const {
164 const SubRunData& subRunData = params.geometry().subRunData();
165
166 subRunData.subRun()->vertexFiller().fillInstanceData(dw,
167 subRunData.startGlyphIndex(),
168 subRunData.glyphCount(),
169 subRunData.subRun()->instanceFlags(),
170 ssboIndices,
171 subRunData.subRun()->glyphs(),
172 params.order().depthAsFloat());
173 }
174
writeUniformsAndTextures(const DrawParams & params,PipelineDataGatherer * gatherer) const175 void BitmapTextRenderStep::writeUniformsAndTextures(const DrawParams& params,
176 PipelineDataGatherer* gatherer) const {
177 SkDEBUGCODE(UniformExpectationsValidator uev(gatherer, this->uniforms());)
178
179 const SubRunData& subRunData = params.geometry().subRunData();
180 unsigned int numProxies;
181 Recorder* recorder = subRunData.recorder();
182 const sk_sp<TextureProxy>* proxies =
183 recorder->priv().atlasProvider()->textAtlasManager()->getProxies(
184 subRunData.subRun()->maskFormat(), &numProxies);
185 SkASSERT(proxies && numProxies > 0);
186
187 // write uniforms
188 gatherer->write(params.transform().matrix()); // subRunDeviceMatrix
189 gatherer->write(subRunData.deviceToLocal());
190 SkV2 atlasDimensionsInverse = {1.f/proxies[0]->dimensions().width(),
191 1.f/proxies[0]->dimensions().height()};
192 gatherer->write(atlasDimensionsInverse);
193
194 // write textures and samplers
195 for (unsigned int i = 0; i < numProxies; ++i) {
196 gatherer->add(proxies[i], {SkFilterMode::kNearest, SkTileMode::kClamp});
197 }
198 // If the atlas has less than 4 active proxies we still need to set up samplers for the shader.
199 for (unsigned int i = numProxies; i < kNumTextAtlasTextures; ++i) {
200 gatherer->add(proxies[0], {SkFilterMode::kNearest, SkTileMode::kClamp});
201 }
202 }
203
204 } // namespace skgpu::graphite
205