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
21namespace 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