Move ProgramImpl definitions into Processor subclass headers.

Move ProgramImpl function definitions into Processor subclass cpp files.

Delete separate h/cpp files.

Modify GrGLSLVaryingHandler::addPassThroughAttribute to break #include
cycle. It now takes a ShaderVar rather than a GP::Attribute, making
it slightly more flexible as the input can be any variable defined
in the vertex shader.

Bug: skia:11358
Change-Id: I94ee8cd44d29e194216592ecae5fd28de785c975
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/438596
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/GrGeometryProcessor.cpp b/src/gpu/GrGeometryProcessor.cpp
index 61f46f3..d87ee46 100644
--- a/src/gpu/GrGeometryProcessor.cpp
+++ b/src/gpu/GrGeometryProcessor.cpp
@@ -7,8 +7,14 @@
 
 #include "src/gpu/GrGeometryProcessor.h"
 
-#include "src/gpu/GrFragmentProcessor.h"
+#include "src/core/SkMatrixPriv.h"
+#include "src/gpu/GrPipeline.h"
+#include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h"
+#include "src/gpu/glsl/GrGLSLProgramBuilder.h"
+#include "src/gpu/glsl/GrGLSLUniformHandler.h"
+#include "src/gpu/glsl/GrGLSLVarying.h"
 
+#include <queue>
 
 GrGeometryProcessor::GrGeometryProcessor(ClassID classID) : GrProcessor(classID) {}
 
@@ -52,3 +58,443 @@
     fSwizzle = swizzle;
     fIsInitialized = true;
 }
+
+//////////////////////////////////////////////////////////////////////////////
+
+using ProgramImpl = GrGeometryProcessor::ProgramImpl;
+
+ProgramImpl::FPCoordsMap ProgramImpl::emitCode(EmitArgs& args, const GrPipeline& pipeline) {
+    GrGPArgs gpArgs;
+    this->onEmitCode(args, &gpArgs);
+
+    GrShaderVar positionVar = gpArgs.fPositionVar;
+    // skia:12198
+    if (args.fGeomProc.willUseGeoShader() || args.fGeomProc.willUseTessellationShaders()) {
+        positionVar = {};
+    }
+    FPCoordsMap transformMap = this->collectTransforms(args.fVertBuilder,
+                                                       args.fVaryingHandler,
+                                                       args.fUniformHandler,
+                                                       gpArgs.fLocalCoordVar,
+                                                       positionVar,
+                                                       pipeline);
+
+    if (args.fGeomProc.willUseTessellationShaders()) {
+        // Tessellation shaders are temporarily responsible for integrating their own code strings
+        // while we work out full support.
+        return transformMap;
+    }
+
+    GrGLSLVertexBuilder* vBuilder = args.fVertBuilder;
+    if (!args.fGeomProc.willUseGeoShader()) {
+        // Emit the vertex position to the hardware in the normalized window coordinates it expects.
+        SkASSERT(kFloat2_GrSLType == gpArgs.fPositionVar.getType() ||
+                 kFloat3_GrSLType == gpArgs.fPositionVar.getType());
+        vBuilder->emitNormalizedSkPosition(gpArgs.fPositionVar.c_str(),
+                                           gpArgs.fPositionVar.getType());
+        if (kFloat2_GrSLType == gpArgs.fPositionVar.getType()) {
+            args.fVaryingHandler->setNoPerspective();
+        }
+    } else {
+        // Since we have a geometry shader, leave the vertex position in Skia device space for now.
+        // The geometry Shader will operate in device space, and then convert the final positions to
+        // normalized hardware window coordinates under the hood, once everything else has finished.
+        // The subclass must call setNoPerspective on the varying handler, if applicable.
+        vBuilder->codeAppendf("sk_Position = float4(%s", gpArgs.fPositionVar.c_str());
+        switch (gpArgs.fPositionVar.getType()) {
+            case kFloat_GrSLType:
+                vBuilder->codeAppend(", 0");
+                [[fallthrough]];
+            case kFloat2_GrSLType:
+                vBuilder->codeAppend(", 0");
+                [[fallthrough]];
+            case kFloat3_GrSLType:
+                vBuilder->codeAppend(", 1");
+                [[fallthrough]];
+            case kFloat4_GrSLType:
+                vBuilder->codeAppend(");");
+                break;
+            default:
+                SK_ABORT("Invalid position var type");
+                break;
+        }
+    }
+    return transformMap;
+}
+
+ProgramImpl::FPCoordsMap ProgramImpl::collectTransforms(GrGLSLVertexBuilder* vb,
+                                                        GrGLSLVaryingHandler* varyingHandler,
+                                                        GrGLSLUniformHandler* uniformHandler,
+                                                        const GrShaderVar& localCoordsVar,
+                                                        const GrShaderVar& positionVar,
+                                                        const GrPipeline& pipeline) {
+    SkASSERT(localCoordsVar.getType() == kFloat2_GrSLType ||
+             localCoordsVar.getType() == kFloat3_GrSLType ||
+             localCoordsVar.getType() == kVoid_GrSLType);
+    SkASSERT(positionVar.getType() == kFloat2_GrSLType ||
+             positionVar.getType() == kFloat3_GrSLType ||
+             positionVar.getType() == kVoid_GrSLType);
+
+    enum class BaseCoord { kNone, kLocal, kPosition };
+
+    auto baseLocalCoordFSVar = [&, baseLocalCoord = GrGLSLVarying()]() mutable {
+        SkASSERT(GrSLTypeIsFloatType(localCoordsVar.getType()));
+        if (baseLocalCoord.type() == kVoid_GrSLType) {
+            // Initialize to the GP provided coordinate
+            baseLocalCoord = GrGLSLVarying(localCoordsVar.getType());
+            varyingHandler->addVarying("LocalCoord", &baseLocalCoord);
+            vb->codeAppendf("%s = %s;\n", baseLocalCoord.vsOut(), localCoordsVar.getName().c_str());
+        }
+        return baseLocalCoord.fsInVar();
+    };
+
+    bool canUsePosition = positionVar.getType() != kVoid_GrSLType;
+
+    FPCoordsMap result;
+    // Performs a pre-order traversal of FP hierarchy rooted at fp and identifies FPs that are
+    // sampled with a series of matrices applied to local coords. For each such FP a varying is
+    // added to the varying handler and added to 'result'.
+    auto liftTransforms = [&, traversalIndex = 0](
+                                  auto& self,
+                                  const GrFragmentProcessor& fp,
+                                  bool hasPerspective,
+                                  const GrFragmentProcessor* lastMatrixFP = nullptr,
+                                  int lastMatrixTraversalIndex = -1,
+                                  BaseCoord baseCoord = BaseCoord::kLocal) mutable -> void {
+        ++traversalIndex;
+        switch (fp.sampleUsage().kind()) {
+            case SkSL::SampleUsage::Kind::kNone:
+                // This should only happen at the root. Otherwise how did this FP get added?
+                SkASSERT(!fp.parent());
+                break;
+            case SkSL::SampleUsage::Kind::kPassThrough:
+                break;
+            case SkSL::SampleUsage::Kind::kUniformMatrix:
+                // Update tracking of last matrix and matrix props.
+                hasPerspective |= fp.sampleUsage().hasPerspective();
+                lastMatrixFP = &fp;
+                lastMatrixTraversalIndex = traversalIndex;
+                break;
+            case SkSL::SampleUsage::Kind::kFragCoord:
+                hasPerspective = positionVar.getType() == kFloat3_GrSLType;
+                lastMatrixFP = nullptr;
+                lastMatrixTraversalIndex = -1;
+                baseCoord = BaseCoord::kPosition;
+                break;
+            case SkSL::SampleUsage::Kind::kExplicit:
+                baseCoord = BaseCoord::kNone;
+                break;
+        }
+
+        auto& [varyingFSVar, hasCoordsParam] = result[&fp];
+        hasCoordsParam = fp.usesSampleCoordsDirectly();
+
+        // We add a varying if we're in a chain of matrices multiplied by local or device coords.
+        // If the coord is the untransformed local coord we add a varying. We don't if it is
+        // untransformed device coords since it doesn't save us anything over "sk_FragCoord.xy". Of
+        // course, if the FP doesn't directly use its coords then we don't add a varying.
+        if (fp.usesSampleCoordsDirectly() &&
+            (baseCoord == BaseCoord::kLocal ||
+             (baseCoord == BaseCoord::kPosition && lastMatrixFP && canUsePosition))) {
+            // Associate the varying with the highest possible node in the FP tree that shares the
+            // same coordinates so that multiple FPs in a subtree can share. If there are no matrix
+            // sample nodes on the way up the tree then directly use the local coord.
+            if (!lastMatrixFP) {
+                varyingFSVar = baseLocalCoordFSVar();
+            } else {
+                // If there is an already a varying that incorporates all matrices from the root to
+                // lastMatrixFP just use it. Otherwise, we add it.
+                auto& [varying, inputCoords, varyingIdx] = fTransformVaryingsMap[lastMatrixFP];
+                if (varying.type() == kVoid_GrSLType) {
+                    varying = GrGLSLVarying(hasPerspective ? kFloat3_GrSLType : kFloat2_GrSLType);
+                    SkString strVaryingName = SkStringPrintf("TransformedCoords_%d",
+                                                             lastMatrixTraversalIndex);
+                    varyingHandler->addVarying(strVaryingName.c_str(), &varying);
+                    inputCoords = baseCoord == BaseCoord::kLocal ? localCoordsVar : positionVar;
+                    varyingIdx = lastMatrixTraversalIndex;
+                }
+                SkASSERT(varyingIdx == lastMatrixTraversalIndex);
+                // The FP will use the varying in the fragment shader as its coords.
+                varyingFSVar = varying.fsInVar();
+            }
+            hasCoordsParam = false;
+        }
+
+        for (int c = 0; c < fp.numChildProcessors(); ++c) {
+            if (auto* child = fp.childProcessor(c)) {
+                self(self,
+                     *child,
+                     hasPerspective,
+                     lastMatrixFP,
+                     lastMatrixTraversalIndex,
+                     baseCoord);
+                // If we have a varying then we never need a param. Otherwise, if one of our
+                // children takes a non-explicit coord then we'll need our coord.
+                hasCoordsParam |= varyingFSVar.getType() == kVoid_GrSLType &&
+                                  !child->sampleUsage().isExplicit()       &&
+                                  !child->sampleUsage().isFragCoord()      &&
+                                  result[child].hasCoordsParam;
+            }
+        }
+    };
+
+    bool hasPerspective = GrSLTypeVecLength(localCoordsVar.getType()) == 3;
+    for (int i = 0; i < pipeline.numFragmentProcessors(); ++i) {
+        liftTransforms(liftTransforms, pipeline.getFragmentProcessor(i), hasPerspective);
+    }
+    return result;
+}
+
+void ProgramImpl::emitTransformCode(GrGLSLVertexBuilder* vb, GrGLSLUniformHandler* uniformHandler) {
+    // Because descendant varyings may be computed using the varyings of ancestor FPs we make
+    // sure to visit the varyings according to FP pre-order traversal by dumping them into a
+    // priority queue.
+    using FPAndInfo = std::tuple<const GrFragmentProcessor*, TransformInfo>;
+    auto compare = [](const FPAndInfo& a, const FPAndInfo& b) {
+        return std::get<1>(a).traversalOrder > std::get<1>(b).traversalOrder;
+    };
+    std::priority_queue<FPAndInfo, std::vector<FPAndInfo>, decltype(compare)> pq(compare);
+    std::for_each(fTransformVaryingsMap.begin(), fTransformVaryingsMap.end(), [&pq](auto entry) {
+        pq.push(entry);
+    });
+    for (; !pq.empty(); pq.pop()) {
+        const auto& [fp, info] = pq.top();
+        // If we recorded a transform info, its sample matrix must be uniform
+        SkASSERT(fp->sampleUsage().isUniformMatrix());
+        GrShaderVar uniform = uniformHandler->liftUniformToVertexShader(
+                *fp->parent(), SkString(SkSL::SampleUsage::MatrixUniformName()));
+        // Start with this matrix and accumulate additional matrices as we walk up the FP tree
+        // to either the base coords or an ancestor FP that has an associated varying.
+        SkString transformExpression = uniform.getName();
+
+        // If we hit an ancestor with a varying on our walk up then save off the varying as the
+        // input to our accumulated transformExpression. Start off assuming we'll reach the root.
+        GrShaderVar inputCoords = info.inputCoords;
+
+        for (const auto* base = fp->parent(); base; base = base->parent()) {
+            if (auto iter = fTransformVaryingsMap.find(base); iter != fTransformVaryingsMap.end()) {
+                // Can stop here, as this varying already holds all transforms from higher FPs
+                // We'll apply the residual transformExpression we've accumulated up from our
+                // starting FP to this varying.
+                inputCoords = iter->second.varying.vsOutVar();
+                break;
+            } else if (base->sampleUsage().isUniformMatrix()) {
+                // Accumulate any matrices along the path to either the original local/device coords
+                // or a parent varying. Getting here means this FP was sampled with a uniform matrix
+                // but all uses of coords below here in the FP hierarchy are beneath additional
+                // matrix samples and thus this node wasn't assigned a varying.
+                GrShaderVar parentUniform = uniformHandler->liftUniformToVertexShader(
+                        *base->parent(), SkString(SkSL::SampleUsage::MatrixUniformName()));
+                transformExpression.appendf(" * %s", parentUniform.getName().c_str());
+            } else if (base->sampleUsage().isFragCoord()) {
+                // Our chain of matrices starts here and is based on the device space position.
+                break;
+            } else {
+                // This intermediate FP is just a pass through and doesn't need to be built
+                // in to the expression, but we must visit its parents in case they add transforms.
+                SkASSERT(base->sampleUsage().isPassThrough() || !base->sampleUsage().isSampled());
+            }
+        }
+
+        SkString inputStr;
+        if (inputCoords.getType() == kFloat2_GrSLType) {
+            inputStr = SkStringPrintf("%s.xy1", inputCoords.getName().c_str());
+        } else {
+            SkASSERT(inputCoords.getType() == kFloat3_GrSLType);
+            inputStr = inputCoords.getName();
+        }
+
+        vb->codeAppend("{\n");
+        if (info.varying.type() == kFloat2_GrSLType) {
+            if (vb->getProgramBuilder()->shaderCaps()->nonsquareMatrixSupport()) {
+                vb->codeAppendf("%s = float3x2(%s) * %s",
+                                info.varying.vsOut(),
+                                transformExpression.c_str(),
+                                inputStr.c_str());
+            } else {
+                vb->codeAppendf("%s = (%s * %s).xy",
+                                info.varying.vsOut(),
+                                transformExpression.c_str(),
+                                inputStr.c_str());
+            }
+        } else {
+            SkASSERT(info.varying.type() == kFloat3_GrSLType);
+            vb->codeAppendf("%s = %s * %s",
+                            info.varying.vsOut(),
+                            transformExpression.c_str(),
+                            inputStr.c_str());
+        }
+        vb->codeAppend(";\n");
+        vb->codeAppend("}\n");
+    }
+    // We don't need this map anymore.
+    fTransformVaryingsMap.clear();
+}
+
+void ProgramImpl::setupUniformColor(GrGLSLFPFragmentBuilder* fragBuilder,
+                                    GrGLSLUniformHandler* uniformHandler,
+                                    const char* outputName,
+                                    UniformHandle* colorUniform) {
+    SkASSERT(colorUniform);
+    const char* stagedLocalVarName;
+    *colorUniform = uniformHandler->addUniform(nullptr,
+                                               kFragment_GrShaderFlag,
+                                               kHalf4_GrSLType,
+                                               "Color",
+                                               &stagedLocalVarName);
+    fragBuilder->codeAppendf("%s = %s;", outputName, stagedLocalVarName);
+    if (fragBuilder->getProgramBuilder()->shaderCaps()->mustObfuscateUniformColor()) {
+        fragBuilder->codeAppendf("%s = max(%s, half4(0));", outputName, outputName);
+    }
+}
+
+void ProgramImpl::SetTransform(const GrGLSLProgramDataManager& pdman,
+                               const GrShaderCaps& shaderCaps,
+                               const UniformHandle& uniform,
+                               const SkMatrix& matrix,
+                               SkMatrix* state) {
+    if (!uniform.isValid() || (state && SkMatrixPriv::CheapEqual(*state, matrix))) {
+        // No update needed
+        return;
+    }
+    if (state) {
+        *state = matrix;
+    }
+    if (matrix.isScaleTranslate() && !shaderCaps.reducedShaderMode()) {
+        // ComputeMatrixKey and writeX() assume the uniform is a float4 (can't assert since nothing
+        // is exposed on a handle, but should be caught lower down).
+        float values[4] = {matrix.getScaleX(), matrix.getTranslateX(),
+                           matrix.getScaleY(), matrix.getTranslateY()};
+        pdman.set4fv(uniform, 1, values);
+    } else {
+        pdman.setSkMatrix(uniform, matrix);
+    }
+}
+
+static void write_passthrough_vertex_position(GrGLSLVertexBuilder* vertBuilder,
+                                              const GrShaderVar& inPos,
+                                              GrShaderVar* outPos) {
+    SkASSERT(inPos.getType() == kFloat3_GrSLType || inPos.getType() == kFloat2_GrSLType);
+    SkString outName = vertBuilder->newTmpVarName(inPos.getName().c_str());
+    outPos->set(inPos.getType(), outName.c_str());
+    vertBuilder->codeAppendf("float%d %s = %s;",
+                             GrSLTypeVecLength(inPos.getType()),
+                             outName.c_str(),
+                             inPos.getName().c_str());
+}
+
+static void write_vertex_position(GrGLSLVertexBuilder* vertBuilder,
+                                  GrGLSLUniformHandler* uniformHandler,
+                                  const GrShaderCaps& shaderCaps,
+                                  const GrShaderVar& inPos,
+                                  const SkMatrix& matrix,
+                                  const char* matrixName,
+                                  GrShaderVar* outPos,
+                                  ProgramImpl::UniformHandle* matrixUniform) {
+    SkASSERT(inPos.getType() == kFloat3_GrSLType || inPos.getType() == kFloat2_GrSLType);
+    SkString outName = vertBuilder->newTmpVarName(inPos.getName().c_str());
+
+    if (matrix.isIdentity() && !shaderCaps.reducedShaderMode()) {
+        write_passthrough_vertex_position(vertBuilder, inPos, outPos);
+        return;
+    }
+    SkASSERT(matrixUniform);
+
+    bool useCompactTransform = matrix.isScaleTranslate() && !shaderCaps.reducedShaderMode();
+    const char* mangledMatrixName;
+    *matrixUniform = uniformHandler->addUniform(nullptr,
+                                                kVertex_GrShaderFlag,
+                                                useCompactTransform ? kFloat4_GrSLType
+                                                                    : kFloat3x3_GrSLType,
+                                                matrixName,
+                                                &mangledMatrixName);
+
+    if (inPos.getType() == kFloat3_GrSLType) {
+        // A float3 stays a float3 whether or not the matrix adds perspective
+        if (useCompactTransform) {
+            vertBuilder->codeAppendf("float3 %s = %s.xz1 * %s + %s.yw0;\n",
+                                     outName.c_str(),
+                                     mangledMatrixName,
+                                     inPos.getName().c_str(),
+                                     mangledMatrixName);
+        } else {
+            vertBuilder->codeAppendf("float3 %s = %s * %s;\n",
+                                     outName.c_str(),
+                                     mangledMatrixName,
+                                     inPos.getName().c_str());
+        }
+        outPos->set(kFloat3_GrSLType, outName.c_str());
+        return;
+    }
+    if (matrix.hasPerspective()) {
+        // A float2 is promoted to a float3 if we add perspective via the matrix
+        SkASSERT(!useCompactTransform);
+        vertBuilder->codeAppendf("float3 %s = (%s * %s.xy1);",
+                                 outName.c_str(),
+                                 mangledMatrixName,
+                                 inPos.getName().c_str());
+        outPos->set(kFloat3_GrSLType, outName.c_str());
+        return;
+    }
+    if (useCompactTransform) {
+        vertBuilder->codeAppendf("float2 %s = %s.xz * %s + %s.yw;\n",
+                                 outName.c_str(),
+                                 mangledMatrixName,
+                                 inPos.getName().c_str(),
+                                 mangledMatrixName);
+    } else if (shaderCaps.nonsquareMatrixSupport()) {
+        vertBuilder->codeAppendf("float2 %s = float3x2(%s) * %s.xy1;\n",
+                                 outName.c_str(),
+                                 mangledMatrixName,
+                                 inPos.getName().c_str());
+    } else {
+        vertBuilder->codeAppendf("float2 %s = (%s * %s.xy1).xy;\n",
+                                 outName.c_str(),
+                                 mangledMatrixName,
+                                 inPos.getName().c_str());
+    }
+    outPos->set(kFloat2_GrSLType, outName.c_str());
+}
+
+void ProgramImpl::WriteOutputPosition(GrGLSLVertexBuilder* vertBuilder,
+                                      GrGPArgs* gpArgs,
+                                      const char* posName) {
+    // writeOutputPosition assumes the incoming pos name points to a float2 variable
+    GrShaderVar inPos(posName, kFloat2_GrSLType);
+    write_passthrough_vertex_position(vertBuilder, inPos, &gpArgs->fPositionVar);
+}
+
+void ProgramImpl::WriteOutputPosition(GrGLSLVertexBuilder* vertBuilder,
+                                      GrGLSLUniformHandler* uniformHandler,
+                                      const GrShaderCaps& shaderCaps,
+                                      GrGPArgs* gpArgs,
+                                      const char* posName,
+                                      const SkMatrix& mat,
+                                      UniformHandle* viewMatrixUniform) {
+    GrShaderVar inPos(posName, kFloat2_GrSLType);
+    write_vertex_position(vertBuilder,
+                          uniformHandler,
+                          shaderCaps,
+                          inPos,
+                          mat,
+                          "viewMatrix",
+                          &gpArgs->fPositionVar,
+                          viewMatrixUniform);
+}
+
+void ProgramImpl::WriteLocalCoord(GrGLSLVertexBuilder* vertBuilder,
+                                  GrGLSLUniformHandler* uniformHandler,
+                                  const GrShaderCaps& shaderCaps,
+                                  GrGPArgs* gpArgs,
+                                  GrShaderVar localVar,
+                                  const SkMatrix& localMatrix,
+                                  UniformHandle* localMatrixUniform) {
+    write_vertex_position(vertBuilder,
+                          uniformHandler,
+                          shaderCaps,
+                          localVar,
+                          localMatrix,
+                          "localMatrix",
+                          &gpArgs->fLocalCoordVar,
+                          localMatrixUniform);
+}