xref: /aosp_15_r20/external/skia/tests/GrMeshTest.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
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 "include/core/SkBitmap.h"
9 #include "include/core/SkBlendMode.h"
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColorSpace.h"
12 #include "include/core/SkPaint.h"
13 #include "include/core/SkRect.h"
14 #include "include/core/SkRefCnt.h"
15 #include "include/core/SkSurfaceProps.h"
16 #include "include/core/SkTypes.h"
17 #include "include/gpu/ganesh/GrDirectContext.h"
18 #include "include/private/SkColorData.h"
19 #include "include/private/base/SkAlignedStorage.h"
20 #include "include/private/base/SkOnce.h"
21 #include "include/private/base/SkTArray.h"
22 #include "include/private/base/SkTo.h"
23 #include "include/private/gpu/ganesh/GrTypesPriv.h"
24 #include "src/base/SkArenaAlloc.h"
25 #include "src/core/SkSLTypeShared.h"
26 #include "src/gpu/KeyBuilder.h"
27 #include "src/gpu/ResourceKey.h"
28 #include "src/gpu/SkBackingFit.h"
29 #include "src/gpu/ganesh/GrBuffer.h"
30 #include "src/gpu/ganesh/GrCaps.h"
31 #include "src/gpu/ganesh/GrColor.h"
32 #include "src/gpu/ganesh/GrDirectContextPriv.h"
33 #include "src/gpu/ganesh/GrDrawIndirectCommand.h"
34 #include "src/gpu/ganesh/GrGeometryProcessor.h"
35 #include "src/gpu/ganesh/GrMeshDrawTarget.h"
36 #include "src/gpu/ganesh/GrOpFlushState.h"
37 #include "src/gpu/ganesh/GrOpsRenderPass.h"
38 #include "src/gpu/ganesh/GrPipeline.h"
39 #include "src/gpu/ganesh/GrPixmap.h"
40 #include "src/gpu/ganesh/GrProcessorAnalysis.h"
41 #include "src/gpu/ganesh/GrProcessorSet.h"
42 #include "src/gpu/ganesh/GrProgramInfo.h"
43 #include "src/gpu/ganesh/GrResourceProvider.h"
44 #include "src/gpu/ganesh/GrShaderCaps.h"
45 #include "src/gpu/ganesh/GrShaderVar.h"
46 #include "src/gpu/ganesh/GrUserStencilSettings.h"
47 #include "src/gpu/ganesh/SurfaceDrawContext.h"
48 #include "src/gpu/ganesh/glsl/GrGLSLFragmentShaderBuilder.h"
49 #include "src/gpu/ganesh/glsl/GrGLSLVarying.h"
50 #include "src/gpu/ganesh/glsl/GrGLSLVertexGeoBuilder.h"
51 #include "src/gpu/ganesh/ops/GrDrawOp.h"
52 #include "src/gpu/ganesh/ops/GrOp.h"
53 #include "src/gpu/ganesh/ops/GrSimpleMeshDrawOpHelper.h"
54 #include "tests/CtsEnforcement.h"
55 #include "tests/Test.h"
56 
57 #include <algorithm>
58 #include <array>
59 #include <cstddef>
60 #include <cstdint>
61 #include <functional>
62 #include <initializer_list>
63 #include <memory>
64 #include <utility>
65 #include <vector>
66 
67 class GrAppliedClip;
68 class GrDstProxyView;
69 class GrGLSLProgramDataManager;
70 class GrRecordingContext;
71 class GrSurfaceProxyView;
72 enum class GrXferBarrierFlags;
73 struct GrContextOptions;
74 
75 using namespace skia_private;
76 
77 #if 0
78 #include "tools/ToolUtils.h"
79 #define WRITE_PNG_CONTEXT_TYPE kANGLE_D3D11_ES3
80 #endif
81 
82 SKGPU_DECLARE_STATIC_UNIQUE_KEY(gIndexBufferKey);
83 
84 static constexpr int kBoxSize = 2;
85 static constexpr int kBoxCountY = 8;
86 static constexpr int kBoxCountX = 8;
87 static constexpr int kBoxCount = kBoxCountY * kBoxCountX;
88 
89 static constexpr int kImageWidth = kBoxCountY * kBoxSize;
90 static constexpr int kImageHeight = kBoxCountX * kBoxSize;
91 
92 static constexpr int kIndexPatternRepeatCount = 3;
93 constexpr uint16_t kIndexPattern[6] = {0, 1, 2, 1, 2, 3};
94 
95 
96 class DrawMeshHelper {
97 public:
DrawMeshHelper(GrOpFlushState * state)98     DrawMeshHelper(GrOpFlushState* state) : fState(state) {}
99 
100     sk_sp<const GrBuffer> getIndexBuffer();
101 
102     sk_sp<const GrBuffer> makeIndexBuffer(const uint16_t[], int count);
103 
makeVertexBuffer(const TArray<T> & data)104     template<typename T> sk_sp<const GrBuffer> makeVertexBuffer(const TArray<T>& data) {
105         return this->makeVertexBuffer(data.begin(), data.size());
106     }
makeVertexBuffer(const std::vector<T> & data)107     template<typename T> sk_sp<const GrBuffer> makeVertexBuffer(const std::vector<T>& data) {
108         return this->makeVertexBuffer(data.data(), data.size());
109     }
110     template<typename T> sk_sp<const GrBuffer> makeVertexBuffer(const T* data, int count);
111 
target()112     GrMeshDrawTarget* target() { return fState; }
113 
114     sk_sp<const GrBuffer> fIndexBuffer;
115     sk_sp<const GrBuffer> fIndexBuffer2;
116     sk_sp<const GrBuffer> fInstBuffer;
117     sk_sp<const GrBuffer> fVertBuffer;
118     sk_sp<const GrBuffer> fVertBuffer2;
119     sk_sp<const GrBuffer> fDrawIndirectBuffer;
120     size_t fDrawIndirectBufferOffset;
121 
122     GrOpsRenderPass* bindPipeline(GrPrimitiveType, bool isInstanced, bool hasVertexBuffer);
123 
124 private:
125     GrOpFlushState* fState;
126 };
127 
128 struct Box {
129     float fX, fY;
130     GrColor fColor;
131 };
132 
133 ////////////////////////////////////////////////////////////////////////////////////////////////////
134 
135 /**
136  * This is a GPU-backend specific test. It tries to test all possible usecases of
137  * GrOpsRenderPass::draw*. The test works by drawing checkerboards of colored boxes, reading back
138  * the pixels, and comparing with expected results. The boxes are drawn on integer boundaries and
139  * the (opaque) colors are chosen from the set (r,g,b) = (0,255)^3, so the GPU renderings ought to
140  * produce exact matches.
141  */
142 
143 static void run_test(GrDirectContext*,
144                      const char* testName,
145                      skiatest::Reporter*,
146                      const std::unique_ptr<skgpu::ganesh::SurfaceDrawContext>&,
147                      const SkBitmap& gold,
148                      std::function<void(DrawMeshHelper*)> prepareFn,
149                      std::function<void(DrawMeshHelper*)> executeFn);
150 
151 #ifdef WRITE_PNG_CONTEXT_TYPE
IsContextTypeForOutputPNGs(skgpu::ContextType type)152 static bool IsContextTypeForOutputPNGs(skgpu::ContextType type) {
153     return type == skgpu::ContextType::WRITE_PNG_CONTEXT_TYPE;
154 }
DEF_GANESH_TEST_FOR_CONTEXTS(GrMeshTest,IsContextTypeForOutputPNGs,reporter,ctxInfo,nullptr)155 DEF_GANESH_TEST_FOR_CONTEXTS(GrMeshTest, IsContextTypeForOutputPNGs, reporter, ctxInfo, nullptr) {
156 #else
157 DEF_GANESH_TEST_FOR_RENDERING_CONTEXTS(GrMeshTest, reporter, ctxInfo, CtsEnforcement::kApiLevel_T) {
158 #endif
159     auto dContext = ctxInfo.directContext();
160 
161     auto sdc = skgpu::ganesh::SurfaceDrawContext::Make(dContext,
162                                                        GrColorType::kRGBA_8888,
163                                                        nullptr,
164                                                        SkBackingFit::kExact,
165                                                        {kImageWidth, kImageHeight},
166                                                        SkSurfaceProps(),
167                                                        /*label=*/{});
168     if (!sdc) {
169         ERRORF(reporter, "could not create render target context.");
170         return;
171     }
172 
173     TArray<Box> boxes;
174     TArray<std::array<Box, 4>> vertexData;
175     SkBitmap gold;
176 
177     // ---- setup ----------
178 
179     SkPaint paint;
180     paint.setBlendMode(SkBlendMode::kSrc);
181     gold.allocN32Pixels(kImageWidth, kImageHeight);
182 
183     SkCanvas goldCanvas(gold);
184 
185     for (int y = 0; y < kBoxCountY; ++y) {
186         for (int x = 0; x < kBoxCountX; ++x) {
187             int c = y + x;
188             int rgb[3] = {-(c & 1) & 0xff, -((c >> 1) & 1) & 0xff, -((c >> 2) & 1) & 0xff};
189 
190             const Box box = boxes.push_back() = {
191                     float(x * kBoxSize),
192                     float(y * kBoxSize),
193                     GrColorPackRGBA(rgb[0], rgb[1], rgb[2], 255)
194             };
195 
196             std::array<Box, 4>& boxVertices = vertexData.push_back();
197             for (int i = 0; i < 4; ++i) {
198                 boxVertices[i] = {
199                         box.fX + (i / 2) * kBoxSize,
200                         box.fY + (i % 2) * kBoxSize,
201                         box.fColor
202                 };
203             }
204 
205             paint.setARGB(255, rgb[0], rgb[1], rgb[2]);
206             goldCanvas.drawRect(SkRect::MakeXYWH(box.fX, box.fY, kBoxSize, kBoxSize), paint);
207         }
208     }
209 
210     // ---- tests ----------
211 
212 #define VALIDATE(buff)                           \
213     do {                                         \
214         if (!buff) {                             \
215             ERRORF(reporter, #buff " is null."); \
216             return;                              \
217         }                                        \
218     } while (0)
219 
220     run_test(dContext, "draw", reporter, sdc, gold,
221              [&](DrawMeshHelper* helper) {
222                  TArray<Box> expandedVertexData;
223                  for (int i = 0; i < kBoxCount; ++i) {
224                      for (int j = 0; j < 6; ++j) {
225                          expandedVertexData.push_back(vertexData[i][kIndexPattern[j]]);
226                      }
227                  }
228 
229                  // Draw boxes one line at a time to exercise base vertex.
230                  helper->fVertBuffer = helper->makeVertexBuffer(expandedVertexData);
231                  VALIDATE(helper->fVertBuffer);
232              },
233              [&](DrawMeshHelper* helper) {
234                  for (int y = 0; y < kBoxCountY; ++y) {
235                      auto pass = helper->bindPipeline(GrPrimitiveType::kTriangles, false, true);
236                      pass->bindBuffers(nullptr, nullptr, helper->fVertBuffer);
237                      pass->draw(kBoxCountX * 6, y * kBoxCountX * 6);
238                  }
239              });
240 
241     run_test(dContext, "drawIndexed", reporter, sdc, gold,
242              [&](DrawMeshHelper* helper) {
243                 helper->fIndexBuffer = helper->getIndexBuffer();
244                 VALIDATE(helper->fIndexBuffer);
245                 helper->fVertBuffer = helper->makeVertexBuffer(vertexData);
246                 VALIDATE(helper->fVertBuffer);
247              },
248              [&](DrawMeshHelper* helper) {
249                 int baseRepetition = 0;
250                 int i = 0;
251                 // Start at various repetitions within the patterned index buffer to exercise base
252                 // index.
253                 while (i < kBoxCount) {
254                     static_assert(kIndexPatternRepeatCount >= 3);
255                     int repetitionCount = std::min(3 - baseRepetition, kBoxCount - i);
256 
257                     auto pass = helper->bindPipeline(GrPrimitiveType::kTriangles, false, true);
258                     pass->bindBuffers(helper->fIndexBuffer, nullptr, helper->fVertBuffer);
259                     pass->drawIndexed(repetitionCount * 6, baseRepetition * 6, baseRepetition * 4,
260                                       (baseRepetition + repetitionCount) * 4 - 1,
261                                       (i - baseRepetition) * 4);
262 
263                     baseRepetition = (baseRepetition + 1) % 3;
264                     i += repetitionCount;
265                 }
266             });
267 
268     run_test(dContext, "drawIndexPattern", reporter, sdc, gold,
269              [&](DrawMeshHelper* helper) {
270                  helper->fIndexBuffer = helper->getIndexBuffer();
271                  VALIDATE(helper->fIndexBuffer);
272                  helper->fVertBuffer = helper->makeVertexBuffer(vertexData);
273                  VALIDATE(helper->fVertBuffer);
274              },
275              [&](DrawMeshHelper* helper) {
276                 // Draw boxes one line at a time to exercise base vertex. drawIndexPattern does
277                 // not support a base index.
278                 for (int y = 0; y < kBoxCountY; ++y) {
279                     auto pass = helper->bindPipeline(GrPrimitiveType::kTriangles, false, true);
280                     pass->bindBuffers(helper->fIndexBuffer, nullptr, helper->fVertBuffer);
281                     pass->drawIndexPattern(6, kBoxCountX, kIndexPatternRepeatCount, 4,
282                                            y * kBoxCountX * 4);
283 
284                 }
285              });
286 
287     for (bool indexed : {false, true}) {
288         if (!dContext->priv().caps()->drawInstancedSupport()) {
289             break;
290         }
291 
292         run_test(dContext, indexed ? "drawIndexedInstanced" : "drawInstanced",
293                  reporter, sdc, gold,
294                  [&](DrawMeshHelper* helper) {
295                      helper->fIndexBuffer = indexed ? helper->getIndexBuffer() : nullptr;
296                      TArray<uint16_t> baseIndexData;
297                      baseIndexData.push_back(kBoxCountX/2 * 6); // for testing base index.
298                      for (int i = 0; i < 6; ++i) {
299                          baseIndexData.push_back(kIndexPattern[i]);
300                      }
301                      helper->fIndexBuffer2 = helper->makeIndexBuffer(baseIndexData.begin(),
302                                                                      baseIndexData.size());
303                      helper->fInstBuffer = helper->makeVertexBuffer(boxes);
304                      VALIDATE(helper->fInstBuffer);
305                      helper->fVertBuffer =
306                              helper->makeVertexBuffer(std::vector<float>{0,0, 0,1, 1,0, 1,1});
307                      VALIDATE(helper->fVertBuffer);
308                      helper->fVertBuffer2 = helper->makeVertexBuffer( // for testing base vertex.
309                          std::vector<float>{-1,-1, -1,-1, 0,0, 0,1, 1,0, 1,1});
310                      VALIDATE(helper->fVertBuffer2);
311                  },
312                  [&](DrawMeshHelper* helper) {
313                      // Draw boxes one line at a time to exercise base instance, base vertex, and
314                      // null vertex buffer.
315                      for (int y = 0; y < kBoxCountY; ++y) {
316                          sk_sp<const GrBuffer> vertexBuffer;
317                          int baseVertex = 0;
318                          switch (y % 3) {
319                              case 0:
320                                  if (dContext->priv().caps()->shaderCaps()->fVertexIDSupport) {
321                                      break;
322                                  }
323                                  [[fallthrough]];
324                              case 1:
325                                  vertexBuffer = helper->fVertBuffer;
326                                  break;
327                              case 2:
328                                  vertexBuffer = helper->fVertBuffer2;
329                                  baseVertex = 2;
330                                  break;
331                          }
332 
333                          GrPrimitiveType primitiveType = indexed ? GrPrimitiveType::kTriangles
334                                                                  : GrPrimitiveType::kTriangleStrip;
335                          auto pass = helper->bindPipeline(primitiveType, true,
336                                                           SkToBool(vertexBuffer));
337                          if (indexed) {
338                              sk_sp<const GrBuffer> indexBuffer = (y % 2) ?
339                                      helper->fIndexBuffer2 : helper->fIndexBuffer;
340                              VALIDATE(indexBuffer);
341                              int baseIndex = (y % 2);
342                              pass->bindBuffers(std::move(indexBuffer), helper->fInstBuffer,
343                                                std::move(vertexBuffer));
344                              pass->drawIndexedInstanced(6, baseIndex, kBoxCountX, y * kBoxCountX,
345                                                         baseVertex);
346                          } else {
347                              pass->bindBuffers(nullptr, helper->fInstBuffer,
348                                                std::move(vertexBuffer));
349                              pass->drawInstanced(kBoxCountX, y * kBoxCountY, 4, baseVertex);
350                          }
351                      }
352                  });
353     }
354 
355     for (bool indexed : {false, true}) {
356         if (!dContext->priv().caps()->drawInstancedSupport()) {
357             break;
358         }
359 
360         run_test(dContext, (indexed) ? "drawIndexedIndirect" : "drawIndirect",
361                  reporter, sdc, gold,
362                  [&](DrawMeshHelper* helper) {
363                      TArray<uint16_t> baseIndexData;
364                      baseIndexData.push_back(kBoxCountX/2 * 6); // for testing base index.
365                      for (int j = 0; j < kBoxCountY; ++j) {
366                          for (int i = 0; i < 6; ++i) {
367                              baseIndexData.push_back(kIndexPattern[i]);
368                          }
369                      }
370                      helper->fIndexBuffer2 = helper->makeIndexBuffer(baseIndexData.begin(),
371                                                                      baseIndexData.size());
372                      VALIDATE(helper->fIndexBuffer2);
373                      helper->fInstBuffer = helper->makeVertexBuffer(boxes);
374                      VALIDATE(helper->fInstBuffer);
375                      helper->fVertBuffer = helper->makeVertexBuffer(std::vector<float>{
376                              -1,-1, 0,0, 0,1, 1,0, 1,1, -1,-1, 0,0, 1,0, 0,1, 1,1});
377                      VALIDATE(helper->fVertBuffer);
378 
379                      GrDrawIndirectWriter indirectWriter;
380                      GrDrawIndexedIndirectWriter indexedIndirectWriter;
381                      if (indexed) {
382                          // Make helper->fDrawIndirectBufferOffset nonzero.
383                          sk_sp<const GrBuffer> ignoredBuff;
384                          size_t ignoredOffset;
385                          // Make a superfluous call to makeDrawIndirectSpace in order to test
386                          // "offsetInBytes!=0" for the actual call to makeDrawIndexedIndirectSpace.
387                          helper->target()->makeDrawIndirectSpace(29, &ignoredBuff, &ignoredOffset);
388                          indexedIndirectWriter = helper->target()->makeDrawIndexedIndirectSpace(
389                                  kBoxCountY, &helper->fDrawIndirectBuffer,
390                                  &helper->fDrawIndirectBufferOffset);
391                      } else {
392                          // Make helper->fDrawIndirectBufferOffset nonzero.
393                          sk_sp<const GrBuffer> ignoredBuff;
394                          size_t ignoredOffset;
395                          // Make a superfluous call to makeDrawIndexedIndirectSpace in order to test
396                          // "offsetInBytes!=0" for the actual call to makeDrawIndirectSpace.
397                          helper->target()->makeDrawIndexedIndirectSpace(7, &ignoredBuff,
398                                                                         &ignoredOffset);
399                          indirectWriter = helper->target()->makeDrawIndirectSpace(
400                                  kBoxCountY, &helper->fDrawIndirectBuffer,
401                                  &helper->fDrawIndirectBufferOffset);
402                      }
403 
404                      // Draw boxes one line at a time to exercise multiple draws.
405                      for (int y = 0; y < kBoxCountY; ++y) {
406                          int baseVertex = (y % 2) ? 1 : 6;
407                          if (indexed) {
408                              int baseIndex = 1 + y * 6;
409                              indexedIndirectWriter.writeIndexed(6, baseIndex, kBoxCountX,
410                                                                 y * kBoxCountX, baseVertex);
411                          } else {
412                              indirectWriter.write(kBoxCountX, y * kBoxCountX, 4, baseVertex);
413                          }
414                      }
415                  },
416                  [&](DrawMeshHelper* helper) {
417                      GrOpsRenderPass* pass;
418                      if (indexed) {
419                          pass = helper->bindPipeline(GrPrimitiveType::kTriangles, true, true);
420                          pass->bindBuffers(helper->fIndexBuffer2, helper->fInstBuffer,
421                                            helper->fVertBuffer);
422                          for (int i = 0; i < 3; ++i) {
423                              int start = kBoxCountY * i / 3;
424                              int end = kBoxCountY * (i + 1) / 3;
425                              size_t offset = helper->fDrawIndirectBufferOffset + start *
426                                              sizeof(GrDrawIndexedIndirectCommand);
427                              pass->drawIndexedIndirect(helper->fDrawIndirectBuffer.get(), offset,
428                                                        end - start);
429                          }
430                      } else {
431                          pass = helper->bindPipeline(GrPrimitiveType::kTriangleStrip, true, true);
432                          pass->bindBuffers(nullptr, helper->fInstBuffer, helper->fVertBuffer);
433                          for (int i = 0; i < 2; ++i) {
434                              int start = kBoxCountY * i / 2;
435                              int end = kBoxCountY * (i + 1) / 2;
436                              size_t offset = helper->fDrawIndirectBufferOffset + start *
437                                              sizeof(GrDrawIndirectCommand);
438                              pass->drawIndirect(helper->fDrawIndirectBuffer.get(), offset,
439                                                 end - start);
440                          }
441                      }
442                  });
443     }
444 }
445 
446 ////////////////////////////////////////////////////////////////////////////////////////////////////
447 
448 namespace {
449 class MeshTestOp : public GrDrawOp {
450 public:
451     DEFINE_OP_CLASS_ID
452 
453     static GrOp::Owner Make(GrRecordingContext* rContext,
454                             std::function<void(DrawMeshHelper*)> prepareFn,
455                             std::function<void(DrawMeshHelper*)> executeFn) {
456         return GrOp::Make<MeshTestOp>(rContext, prepareFn, executeFn);
457     }
458 
459 private:
460     friend class GrOp;  // for ctor
461 
462     MeshTestOp(std::function<void(DrawMeshHelper*)> prepareFn,
463                std::function<void(DrawMeshHelper*)> executeFn)
464             : INHERITED(ClassID()), fPrepareFn(prepareFn), fExecuteFn(executeFn) {
465         this->setBounds(
466                 SkRect::MakeIWH(kImageWidth, kImageHeight), HasAABloat::kNo, IsHairline::kNo);
467     }
468 
469     const char* name() const override { return "GrMeshTestOp"; }
470     FixedFunctionFlags fixedFunctionFlags() const override { return FixedFunctionFlags::kNone; }
471     GrProcessorSet::Analysis finalize(const GrCaps&, const GrAppliedClip*, GrClampType) override {
472         return GrProcessorSet::EmptySetAnalysis();
473     }
474 
475     void onPrePrepare(GrRecordingContext*,
476                       const GrSurfaceProxyView& writeView,
477                       GrAppliedClip*,
478                       const GrDstProxyView&,
479                       GrXferBarrierFlags renderPassXferBarriers,
480                       GrLoadOp colorLoadOp) override {}
481     void onPrepare(GrOpFlushState* state) override {
482         fHelper = std::make_unique<DrawMeshHelper>(state);
483         fPrepareFn(fHelper.get());
484     }
485     void onExecute(GrOpFlushState* state, const SkRect& chainBounds) override {
486         fExecuteFn(fHelper.get());
487     }
488 
489     std::unique_ptr<DrawMeshHelper> fHelper;
490     std::function<void(DrawMeshHelper*)> fPrepareFn;
491     std::function<void(DrawMeshHelper*)> fExecuteFn;
492 
493     using INHERITED = GrDrawOp;
494 };
495 
496 class MeshTestProcessor : public GrGeometryProcessor {
497 public:
498     static GrGeometryProcessor* Make(SkArenaAlloc* arena, bool instanced, bool hasVertexBuffer) {
499         return arena->make([&](void* ptr) {
500             return new (ptr) MeshTestProcessor(instanced, hasVertexBuffer);
501         });
502     }
503 
504     const char* name() const override { return "GrMeshTestProcessor"; }
505 
506     void addToKey(const GrShaderCaps&, skgpu::KeyBuilder* b) const final {
507         b->add32(fInstanceLocation.isInitialized());
508         b->add32(fVertexPosition.isInitialized());
509     }
510 
511     std::unique_ptr<ProgramImpl> makeProgramImpl(const GrShaderCaps&) const final;
512 
513 private:
514     class Impl;
515 
516     const Attribute& inColor() const {
517         return fVertexColor.isInitialized() ? fVertexColor : fInstanceColor;
518     }
519 
520     MeshTestProcessor(bool instanced, bool hasVertexBuffer)
521             : INHERITED(kGrMeshTestProcessor_ClassID) {
522         if (instanced) {
523             fInstanceLocation = {"location", kFloat2_GrVertexAttribType, SkSLType::kHalf2};
524             fInstanceColor = {"color", kUByte4_norm_GrVertexAttribType, SkSLType::kHalf4};
525             this->setInstanceAttributesWithImplicitOffsets(&fInstanceLocation, 2);
526             if (hasVertexBuffer) {
527                 fVertexPosition = {"vertex", kFloat2_GrVertexAttribType, SkSLType::kHalf2};
528                 this->setVertexAttributesWithImplicitOffsets(&fVertexPosition, 1);
529             }
530         } else {
531             fVertexPosition = {"vertex", kFloat2_GrVertexAttribType, SkSLType::kHalf2};
532             fVertexColor = {"color", kUByte4_norm_GrVertexAttribType, SkSLType::kHalf4};
533             this->setVertexAttributesWithImplicitOffsets(&fVertexPosition, 2);
534         }
535     }
536 
537     Attribute fVertexPosition;
538     Attribute fVertexColor;
539 
540     Attribute fInstanceLocation;
541     Attribute fInstanceColor;
542 
543     using INHERITED = GrGeometryProcessor;
544 };
545 }  // anonymous namespace
546 
547 std::unique_ptr<GrGeometryProcessor::ProgramImpl> MeshTestProcessor::makeProgramImpl(
548         const GrShaderCaps&) const {
549     class Impl : public ProgramImpl {
550     public:
551         void setData(const GrGLSLProgramDataManager&,
552                      const GrShaderCaps&,
553                      const GrGeometryProcessor&) final {}
554 
555     private:
556         void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) final {
557             const MeshTestProcessor& mp = args.fGeomProc.cast<MeshTestProcessor>();
558             GrGLSLVertexBuilder* v = args.fVertBuilder;
559             GrGLSLFPFragmentBuilder* f = args.fFragBuilder;
560 
561             GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
562             varyingHandler->emitAttributes(mp);
563             f->codeAppendf("half4 %s;", args.fOutputColor);
564             varyingHandler->addPassThroughAttribute(mp.inColor().asShaderVar(), args.fOutputColor);
565 
566             if (!mp.fInstanceLocation.isInitialized()) {
567                 v->codeAppendf("float2 vertex = %s;", mp.fVertexPosition.name());
568             } else {
569                 if (mp.fVertexPosition.isInitialized()) {
570                     v->codeAppendf("float2 offset = %s;", mp.fVertexPosition.name());
571                 } else {
572                     v->codeAppend("float2 offset = float2(sk_VertexID / 2, sk_VertexID % 2);");
573                 }
574                 v->codeAppendf("float2 vertex = %s + offset * %i;", mp.fInstanceLocation.name(),
575                                kBoxSize);
576             }
577             gpArgs->fPositionVar.set(SkSLType::kFloat2, "vertex");
578 
579             f->codeAppendf("const half4 %s = half4(1);", args.fOutputCoverage);
580         }
581     };
582 
583     return std::make_unique<Impl>();
584 }
585 
586 ////////////////////////////////////////////////////////////////////////////////////////////////////
587 
588 sk_sp<const GrBuffer> DrawMeshHelper::makeIndexBuffer(const uint16_t indices[], int count) {
589     return fState->resourceProvider()->createBuffer(indices,
590                                                     count*sizeof(uint16_t),
591                                                     GrGpuBufferType::kIndex,
592                                                     kDynamic_GrAccessPattern);
593 }
594 
595 template<typename T>
596 sk_sp<const GrBuffer> DrawMeshHelper::makeVertexBuffer(const T* data, int count) {
597     return fState->resourceProvider()->createBuffer(data,
598                                                     count*sizeof(T),
599                                                     GrGpuBufferType::kVertex,
600                                                     kDynamic_GrAccessPattern);
601 }
602 
603 sk_sp<const GrBuffer> DrawMeshHelper::getIndexBuffer() {
604     SKGPU_DEFINE_STATIC_UNIQUE_KEY(gIndexBufferKey);
605     return fState->resourceProvider()->findOrCreatePatternedIndexBuffer(
606             kIndexPattern, 6, kIndexPatternRepeatCount, 4, gIndexBufferKey);
607 }
608 
609 GrOpsRenderPass* DrawMeshHelper::bindPipeline(GrPrimitiveType primitiveType, bool isInstanced,
610                                               bool hasVertexBuffer) {
611     GrProcessorSet processorSet(SkBlendMode::kSrc);
612 
613     // TODO: add a GrProcessorSet testing helper to make this easier
614     SkPMColor4f overrideColor;
615     processorSet.finalize(GrProcessorAnalysisColor(),
616                           GrProcessorAnalysisCoverage::kNone,
617                           fState->appliedClip(),
618                           nullptr,
619                           fState->caps(),
620                           GrClampType::kAuto,
621                           &overrideColor);
622 
623     auto pipeline = GrSimpleMeshDrawOpHelper::CreatePipeline(fState,
624                                                              std::move(processorSet),
625                                                              GrPipeline::InputFlags::kNone);
626 
627     GrGeometryProcessor* mtp = MeshTestProcessor::Make(fState->allocator(), isInstanced,
628                                                        hasVertexBuffer);
629 
630     GrProgramInfo programInfo(fState->caps(), fState->writeView(), fState->usesMSAASurface(),
631                               pipeline, &GrUserStencilSettings::kUnused, mtp, primitiveType,
632                               fState->renderPassBarriers(), fState->colorLoadOp());
633 
634     fState->opsRenderPass()->bindPipeline(programInfo, SkRect::MakeIWH(kImageWidth, kImageHeight));
635     return fState->opsRenderPass();
636 }
637 
638 static void run_test(GrDirectContext* dContext,
639                      const char* testName,
640                      skiatest::Reporter* reporter,
641                      const std::unique_ptr<skgpu::ganesh::SurfaceDrawContext>& sdc,
642                      const SkBitmap& gold,
643                      std::function<void(DrawMeshHelper*)> prepareFn,
644                      std::function<void(DrawMeshHelper*)> executeFn) {
645     const int w = gold.width(), h = gold.height();
646     const uint32_t* goldPx = reinterpret_cast<const uint32_t*>(gold.getPixels());
647     if (h != sdc->height() || w != sdc->width()) {
648         ERRORF(reporter, "[%s] expectation and rtc not compatible (?).", testName);
649         return;
650     }
651     if (sizeof(uint32_t) * kImageWidth != gold.rowBytes()) {
652         ERRORF(reporter, "[%s] unexpected row bytes in gold image", testName);
653         return;
654     }
655 
656     GrPixmap resultPM = GrPixmap::Allocate(gold.info());
657     sdc->clear(SkPMColor4f::FromBytes_RGBA(0xbaaaaaad));
658     sdc->addDrawOp(MeshTestOp::Make(dContext, prepareFn, executeFn));
659 
660     sdc->readPixels(dContext, resultPM, {0, 0});
661 
662 #ifdef WRITE_PNG_CONTEXT_TYPE
663 #define STRINGIFY(X) #X
664 #define TOSTRING(X) STRINGIFY(X)
665     SkString filename;
666     filename.printf("GrMeshTest_%s_%s.png", TOSTRING(WRITE_PNG_CONTEXT_TYPE), testName);
667     SkDebugf("writing %s...\n", filename.c_str());
668     ToolUtils::EncodeImageToPngFile(filename.c_str(), resultPM);
669 #endif
670 
671     for (int y = 0; y < h; ++y) {
672         for (int x = 0; x < w; ++x) {
673             uint32_t expected = goldPx[y * kImageWidth + x];
674             uint32_t actual = static_cast<uint32_t*>(resultPM.addr())[y * kImageWidth + x];
675             if (expected != actual) {
676                 ERRORF(reporter, "[%s] pixel (%i,%i): got 0x%x expected 0x%x",
677                        testName, x, y, actual, expected);
678                 return;
679             }
680         }
681     }
682 }
683