Michael Ludwig | 460eb5e | 2018-10-29 11:09:29 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2018 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 | #ifndef GrQuadPerEdgeAA_DEFINED |
| 9 | #define GrQuadPerEdgeAA_DEFINED |
| 10 | |
| 11 | #include "GrColor.h" |
Michael Ludwig | 20e909e | 2018-10-30 10:43:57 -0400 | [diff] [blame^] | 12 | #include "GrPrimitiveProcessor.h" |
Michael Ludwig | 460eb5e | 2018-10-29 11:09:29 -0400 | [diff] [blame] | 13 | #include "GrSamplerState.h" |
| 14 | #include "GrTypesPriv.h" |
Michael Ludwig | 20e909e | 2018-10-30 10:43:57 -0400 | [diff] [blame^] | 15 | #include "glsl/GrGLSLPrimitiveProcessor.h" |
Michael Ludwig | 460eb5e | 2018-10-29 11:09:29 -0400 | [diff] [blame] | 16 | #include "SkPoint.h" |
| 17 | #include "SkPoint3.h" |
| 18 | |
Michael Ludwig | 20e909e | 2018-10-30 10:43:57 -0400 | [diff] [blame^] | 19 | class GrGLSLColorSpaceXformHelper; |
Michael Ludwig | 460eb5e | 2018-10-29 11:09:29 -0400 | [diff] [blame] | 20 | class GrPerspQuad; |
| 21 | |
| 22 | class GrQuadPerEdgeAA { |
| 23 | public: |
| 24 | enum class Domain : bool { kNo = false, kYes = true }; |
| 25 | |
| 26 | // The vertex template provides a clean way of specifying the layout and components of a vertex |
| 27 | // for a per-edge aa quad. However, because there are so many permutations possible, the struct |
| 28 | // is defined this way to take away all layout control from the compiler and make |
| 29 | // sure that it matches what we need to send to the GPU. |
| 30 | // |
| 31 | // It is expected that most code using these vertices will only need to call the templated |
| 32 | // Tessellate() function with an appropriately sized vertex buffer and not need to modify or |
| 33 | // read the fields of a particular vertex. |
| 34 | template <int PosDim, typename C, int LocalPosDim, Domain D, GrAA AA> |
| 35 | struct Vertex { |
| 36 | using Color = C; |
| 37 | static constexpr GrAA kAA = AA; |
| 38 | static constexpr Domain kDomain = D; |
| 39 | static constexpr size_t kPositionDim = PosDim; |
| 40 | static constexpr size_t kLocalPositionDim = LocalPosDim; |
| 41 | |
| 42 | static constexpr size_t kPositionOffset = 0; |
| 43 | static constexpr size_t kPositionSize = PosDim * sizeof(float); |
| 44 | |
| 45 | static constexpr size_t kColorOffset = kPositionOffset + kPositionSize; |
| 46 | static constexpr size_t kColorSize = sizeof(Color); |
| 47 | |
| 48 | static constexpr size_t kLocalPositionOffset = kColorOffset + kColorSize; |
| 49 | static constexpr size_t kLocalPositionSize = LocalPosDim * sizeof(float); |
| 50 | |
| 51 | static constexpr size_t kDomainOffset = kLocalPositionOffset + kLocalPositionSize; |
| 52 | static constexpr size_t kDomainSize = D == Domain::kYes ? sizeof(SkRect) : 0; |
| 53 | |
| 54 | static constexpr size_t kAAOffset = kDomainOffset + kDomainSize; |
| 55 | static constexpr size_t kAASize = AA == GrAA::kYes ? 4 * sizeof(SkPoint3) : 0; |
| 56 | |
| 57 | static constexpr size_t kVertexSize = kAAOffset + kAASize; |
| 58 | |
| 59 | // Make sure sizeof(Vertex<...>) == kVertexSize |
| 60 | char fData[kVertexSize]; |
| 61 | }; |
| 62 | |
Michael Ludwig | 20e909e | 2018-10-30 10:43:57 -0400 | [diff] [blame^] | 63 | // Utility class that manages the attribute state necessary to render a particular batch of |
| 64 | // quads. It is similar to a geometry processor but is meant to be included in a has-a |
| 65 | // relationship by specialized GP's that provide further functionality on top of the per-edge AA |
| 66 | // coverage. |
| 67 | // |
| 68 | // For performance reasons, this uses fixed names for the attribute variables; since it defines |
| 69 | // the majority of attributes a GP will likely need, this shouldn't be too limiting. |
| 70 | // |
| 71 | // In terms of responsibilities, the actual geometry processor must still call emitTransforms(), |
| 72 | // using the localCoords() attribute as the 4th argument; it must set the transform data helper |
| 73 | // to use the identity matrix; it must manage the color space transform for the quad's paint |
| 74 | // color; it should include getKey() in the geometry processor's key builder; and it should |
| 75 | // return these managed attributes from its onVertexAttribute() function. |
| 76 | class GPAttributes { |
| 77 | public: |
| 78 | using Attribute = GrPrimitiveProcessor::Attribute; |
| 79 | |
| 80 | GPAttributes(int posDim, int localDim, bool hasColor, GrAAType aa, Domain domain); |
| 81 | |
| 82 | const Attribute& positions() const { return fPositions; } |
| 83 | const Attribute& colors() const { return fColors; } |
| 84 | const Attribute& localCoords() const { return fLocalCoords; } |
| 85 | const Attribute& domain() const { return fDomain; } |
| 86 | const Attribute& edges(int i) const { return fAAEdges[i]; } |
| 87 | |
| 88 | bool hasVertexColors() const { return fColors.isInitialized(); } |
| 89 | |
| 90 | bool usesCoverageAA() const { return fAAEdges[0].isInitialized(); } |
| 91 | |
| 92 | bool hasLocalCoords() const { return fLocalCoords.isInitialized(); } |
| 93 | |
| 94 | bool hasDomain() const { return fDomain.isInitialized(); } |
| 95 | |
| 96 | bool needsPerspectiveInterpolation() const; |
| 97 | |
| 98 | int vertexAttributeCount() const; |
| 99 | |
| 100 | uint32_t getKey() const; |
| 101 | |
| 102 | // Functions to be called at appropriate times in a processor's onEmitCode() block. These |
| 103 | // are separated into discrete pieces so that they can be interleaved with the rest of the |
| 104 | // processor's shader code as needed. The functions take char* arguments for the names of |
| 105 | // variables the emitted code must declare, so that the calling GP can ensure there's no |
| 106 | // naming conflicts with their own code. |
| 107 | |
| 108 | void emitColor(GrGLSLPrimitiveProcessor::EmitArgs& args, |
| 109 | GrGLSLColorSpaceXformHelper* colorSpaceXformHelper, |
| 110 | const char* colorVarName) const; |
| 111 | |
| 112 | // localCoordName will be declared as a float2, with any domain applied after any |
| 113 | // perspective division is performed. |
| 114 | // |
| 115 | // Note: this should only be used if the local coordinates need to be passed separately |
| 116 | // from the standard coord transform process that is used by FPs. |
| 117 | // FIXME: This can go in two directions from here, if GrTextureOp stops needing per-quad |
| 118 | // domains it can be removed and GrTextureOp rewritten to use coord transforms. Or |
| 119 | // emitTransform() in the primitive builder can be updated to have a notion of domain for |
| 120 | // local coords, and all domain-needing code (blurs, filters, etc.) can switch to that magic |
| 121 | void emitExplicitLocalCoords(GrGLSLPrimitiveProcessor::EmitArgs& args, |
| 122 | const char* localCoordName, const char* domainVarName) const; |
| 123 | |
| 124 | void emitCoverage(GrGLSLPrimitiveProcessor::EmitArgs& args, const char* edgeDistName) const; |
| 125 | private: |
| 126 | Attribute fPositions; // named "position" in SkSL |
| 127 | Attribute fColors; // named "color" in SkSL |
| 128 | Attribute fLocalCoords; // named "localCoord" in SkSL |
| 129 | Attribute fDomain; // named "domain" in SkSL |
| 130 | Attribute fAAEdges[4]; // named "aaEdgeX" for X = 0,1,2,3 |
| 131 | }; |
| 132 | |
Michael Ludwig | 460eb5e | 2018-10-29 11:09:29 -0400 | [diff] [blame] | 133 | // Tessellate the given quad specification into the vertices buffer. If the specific vertex |
| 134 | // type does not use color, local positions, domain, etc. then the passed in values used for |
| 135 | // that field will be ignored. |
| 136 | template<typename V> |
| 137 | static void Tessellate(V* vertices, const GrPerspQuad& deviceQuad, typename V::Color color, |
| 138 | const GrPerspQuad& srcQuad, const SkRect& domain, GrQuadAAFlags aa) { |
| 139 | static_assert(sizeof(V) == V::kVertexSize, "Incorrect vertex size"); |
| 140 | static constexpr bool useCoverageAA = V::kAA == GrAA::kYes; |
| 141 | float localStorage[4 * (V::kPositionDim + V::kLocalPositionDim + (useCoverageAA ? 3 : 0))]; |
| 142 | TessellateImpl(vertices, V::kVertexSize, localStorage, |
| 143 | deviceQuad, V::kPositionDim, V::kPositionOffset, V::kPositionSize, |
| 144 | &color, V::kColorOffset, V::kColorSize, |
| 145 | srcQuad, V::kLocalPositionDim, V::kLocalPositionOffset, V::kLocalPositionSize, |
| 146 | &domain, V::kDomainOffset, V::kDomainSize, |
| 147 | aa, V::kAAOffset, V::kAASize); |
| 148 | } |
| 149 | |
| 150 | private: |
| 151 | // Don't let the "namespace" class be instantiated |
| 152 | GrQuadPerEdgeAA(); |
| 153 | |
| 154 | // Internal implementation that can handle all vertex template variations without being |
| 155 | // replicated by the template in order to keep code size down. |
| 156 | // |
| 157 | // This uses the field sizes to determine if particular data needs to be computed. The arguments |
| 158 | // are arranged so that the data and field specification match the field declaration order of |
| 159 | // the vertex type (pos, color, localPos, domain, aa). |
| 160 | // |
| 161 | // localStorage must be have a length > 4 * (devDimCt + srcDimCt + (aa ? 3 : 0)) and is assumed |
| 162 | // to be a pointer to a local variable in the wrapping template's stack. This is done instead of |
| 163 | // always allocating 36 floats in this function (36 is maximum needed). The minimum needed for a |
| 164 | // non-AA 2D quad with no local coordinates is just 8. |
| 165 | static void TessellateImpl(void* vertices, size_t vertexSize, float* localStorage, |
| 166 | const GrPerspQuad& deviceQuad, int posDim, size_t posOffset, size_t posSize, |
| 167 | const void* color, size_t colorOffset, size_t colorSize, |
| 168 | const GrPerspQuad& srcQuad, int srcDim, size_t srcOffset, size_t srcSize, |
| 169 | const void* domain, size_t domainOffset, size_t domainSize, |
| 170 | GrQuadAAFlags aaFlags, size_t aaOffset, size_t aaSize); |
| 171 | }; |
| 172 | |
| 173 | #endif // GrQuadPerEdgeAA_DEFINED |