1 // Copyright 2016 The SwiftShader Authors. All Rights Reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef sw_Clipper_hpp 16 #define sw_Clipper_hpp 17 18 #include "Plane.hpp" 19 #include "Common/Types.hpp" 20 21 namespace sw 22 { 23 struct Polygon; 24 struct DrawCall; 25 struct DrawData; 26 27 class Clipper 28 { 29 public: 30 enum ClipFlags 31 { 32 // Indicates the vertex is outside the respective frustum plane 33 CLIP_RIGHT = 1 << 0, 34 CLIP_TOP = 1 << 1, 35 CLIP_FAR = 1 << 2, 36 CLIP_LEFT = 1 << 3, 37 CLIP_BOTTOM = 1 << 4, 38 CLIP_NEAR = 1 << 5, 39 40 CLIP_FRUSTUM = 0x003F, 41 42 CLIP_FINITE = 1 << 7, // All position coordinates are finite 43 44 // User-defined clipping planes 45 CLIP_PLANE0 = 1 << 8, 46 CLIP_PLANE1 = 1 << 9, 47 CLIP_PLANE2 = 1 << 10, 48 CLIP_PLANE3 = 1 << 11, 49 CLIP_PLANE4 = 1 << 12, 50 CLIP_PLANE5 = 1 << 13, 51 52 CLIP_USER = 0x3F00 53 }; 54 55 Clipper(bool symmetricNormalizedDepth); 56 57 ~Clipper(); 58 59 unsigned int computeClipFlags(const float4 &v); 60 bool clip(Polygon &polygon, int clipFlagsOr, const DrawCall &draw); 61 62 private: 63 void clipNear(Polygon &polygon); 64 void clipFar(Polygon &polygon); 65 void clipLeft(Polygon &polygon); 66 void clipRight(Polygon &polygon); 67 void clipTop(Polygon &polygon); 68 void clipBottom(Polygon &polygon); 69 void clipPlane(Polygon &polygon, const Plane &plane); 70 71 void clipEdge(float4 &Vo, const float4 &Vi, const float4 &Vj, float di, float dj) const; 72 73 float n; // Near clip plane distance 74 }; 75 } 76 77 #endif // sw_Clipper_hpp 78