1 /* 2 * Copyright 2016 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 9 #ifndef GrStencilSettings_DEFINED 10 #define GrStencilSettings_DEFINED 11 12 #include "include/core/SkRegion.h" 13 #include "src/gpu/GrUserStencilSettings.h" 14 15 namespace skgpu { 16 class KeyBuilder; 17 } 18 19 enum class GrStencilTest : uint16_t { 20 kAlways, 21 kNever, 22 kGreater, 23 kGEqual, 24 kLess, 25 kLEqual, 26 kEqual, 27 kNotEqual 28 }; 29 static constexpr int kGrStencilTestCount = 1 + (int)GrStencilTest::kNotEqual; 30 31 enum class GrStencilOp : uint8_t { 32 kKeep, 33 kZero, 34 kReplace, // Replace stencil value with fRef (only the bits enabled in fWriteMask). 35 kInvert, 36 kIncWrap, 37 kDecWrap, 38 // NOTE: clamping occurs before the write mask. So if the MSB is zero and masked out, stencil 39 // values will still wrap when using clamping ops. 40 kIncClamp, 41 kDecClamp 42 }; 43 static constexpr int kGrStencilOpCount = 1 + (int)GrStencilOp::kDecClamp; 44 45 /** 46 * This class defines concrete stencil settings that map directly to the underlying hardware. It 47 * is deduced from user stencil settings, stencil clip status, and the number of bits in the 48 * target stencil buffer. 49 */ 50 class GrStencilSettings { 51 public: GrStencilSettings()52 GrStencilSettings() { this->setDisabled(); } GrStencilSettings(const GrUserStencilSettings & user,bool hasStencilClip,int numStencilBits)53 GrStencilSettings(const GrUserStencilSettings& user, bool hasStencilClip, int numStencilBits) { 54 this->reset(user, hasStencilClip, numStencilBits); 55 } GrStencilSettings(const GrStencilSettings & that)56 GrStencilSettings(const GrStencilSettings& that) { this->reset(that); } 57 GrStencilSettings& operator=(const GrStencilSettings& that) { this->reset(that); return *this; } 58 invalidate()59 void invalidate() { fFlags |= kInvalid_PrivateFlag; } setDisabled()60 void setDisabled() { fFlags = kAll_StencilFlags; } 61 void reset(const GrUserStencilSettings&, bool hasStencilClip, int numStencilBits); 62 void reset(const GrStencilSettings&); 63 isValid()64 bool isValid() const { return !(fFlags & kInvalid_PrivateFlag); } isDisabled()65 bool isDisabled() const { SkASSERT(this->isValid()); return fFlags & kDisabled_StencilFlag; } doesWrite()66 bool doesWrite() const { SkASSERT(this->isValid()); 67 return !(fFlags & kNoModifyStencil_StencilFlag); } isTwoSided()68 bool isTwoSided() const { SkASSERT(this->isValid()); 69 return !(fFlags & kSingleSided_StencilFlag); } usesWrapOp()70 bool usesWrapOp() const { SkASSERT(this->isValid()); 71 return !(fFlags & kNoWrapOps_StencilFlag); } 72 73 void genKey(skgpu::KeyBuilder* b, bool includeRefsAndMasks) const; 74 75 bool operator!=(const GrStencilSettings& that) const { return !(*this == that); } 76 bool operator==(const GrStencilSettings&) const; 77 78 struct Face : public GrTStencilFaceSettings<GrStencilTest, GrStencilOp> { 79 void reset(const GrUserStencilSettings::Face&, bool useStencilClip, int numStencilBits); 80 void setDisabled(); 81 }; 82 singleSidedFace()83 const Face& singleSidedFace() const { 84 SkASSERT(!this->isDisabled()); 85 SkASSERT(!this->isTwoSided()); 86 return fCWFace; 87 } 88 // Returns the stencil settings for triangles that wind clockwise in "post-origin" space. 89 // (i.e., the space that results after a potential y-axis flip on device space for bottom-left 90 // origins.) postOriginCWFace(GrSurfaceOrigin origin)91 const Face& postOriginCWFace(GrSurfaceOrigin origin) const { 92 SkASSERT(this->isTwoSided()); 93 return (kTopLeft_GrSurfaceOrigin == origin) ? fCWFace : fCCWFace; 94 } 95 // Returns the stencil settings for triangles that wind counter-clockwise in "post-origin" 96 // space. (i.e., the space that results after a potential y-axis flip on device space for 97 // bottom-left origins.) postOriginCCWFace(GrSurfaceOrigin origin)98 const Face& postOriginCCWFace(GrSurfaceOrigin origin) const { 99 SkASSERT(this->isTwoSided()); 100 return (kTopLeft_GrSurfaceOrigin == origin) ? fCCWFace : fCWFace; 101 } 102 103 /** Gets the user stencil settings to directly set the clip bit. */ 104 static const GrUserStencilSettings* SetClipBitSettings(bool setToInside); 105 106 private: 107 // Internal flag for backends to optionally mark their tracked stencil state as invalid. 108 // NOTE: This value is outside the declared range of GrStencilFlags, but since that type is 109 // explicitly backed by 'int', it can still represent this constant. clang 11 complains about 110 // mixing enum types in bit operations, so this works around that. 111 inline static constexpr GrStencilFlags kInvalid_PrivateFlag = 112 static_cast<GrStencilFlags>(kLast_StencilFlag << 1); 113 114 uint32_t fFlags; 115 Face fCWFace; 116 Face fCCWFace; 117 }; 118 119 #endif 120