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_Primitive_hpp
16#define sw_Primitive_hpp
17
18#include "Vertex.hpp"
19#include "Main/Config.hpp"
20
21namespace sw
22{
23	struct Triangle
24	{
25		Vertex v0;
26		Vertex v1;
27		Vertex v2;
28	};
29
30	struct PlaneEquation   // z = A * x + B * y + C
31	{
32		float4 A;
33		float4 B;
34		float4 C;
35	};
36
37	struct Primitive
38	{
39		int yMin;
40		int yMax;
41
42		float4 xQuad;
43		float4 yQuad;
44
45		PlaneEquation z;
46		PlaneEquation w;
47
48		union
49		{
50			struct
51			{
52				PlaneEquation C[2][4];
53				PlaneEquation T[8][4];
54				PlaneEquation f;
55			};
56
57			PlaneEquation V[MAX_FRAGMENT_INPUTS][4];
58		};
59
60		float area;
61
62		// Masks for two-sided stencil
63		int64_t clockwiseMask;
64		int64_t invClockwiseMask;
65
66		struct Span
67		{
68			unsigned short left;
69			unsigned short right;
70		};
71
72		// The rasterizer adds a zero length span to the top and bottom of the polygon to allow
73		// for 2x2 pixel processing. We need an even number of spans to keep accesses aligned.
74		Span outlineUnderflow[2];
75		Span outline[OUTLINE_RESOLUTION];
76		Span outlineOverflow[2];
77	};
78}
79
80#endif   // sw_Primitive_hpp
81