1 /**
2 * \file stencil.h
3 * Stencil operations.
4 */
5
6 /*
7 * Mesa 3-D graphics library
8 *
9 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
10 *
11 * Permission is hereby granted, free of charge, to any person obtaining a
12 * copy of this software and associated documentation files (the "Software"),
13 * to deal in the Software without restriction, including without limitation
14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15 * and/or sell copies of the Software, and to permit persons to whom the
16 * Software is furnished to do so, subject to the following conditions:
17 *
18 * The above copyright notice and this permission notice shall be included
19 * in all copies or substantial portions of the Software.
20 *
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
22 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
24 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
25 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
26 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
27 * OTHER DEALINGS IN THE SOFTWARE.
28 */
29
30
31 #ifndef STENCIL_H
32 #define STENCIL_H
33
34
35 #include "glheader.h"
36 #include "macros.h"
37
38 struct gl_context;
39
40 extern void GLAPIENTRY
41 _mesa_ClearStencil( GLint s );
42
43
44 void GLAPIENTRY
45 _mesa_StencilFunc_no_error(GLenum func, GLint ref, GLuint mask);
46
47 extern void GLAPIENTRY
48 _mesa_StencilFunc(GLenum func, GLint ref, GLuint mask);
49
50
51 extern void GLAPIENTRY
52 _mesa_StencilMask( GLuint mask );
53
54 void GLAPIENTRY
55 _mesa_StencilOp_no_error(GLenum fail, GLenum zfail, GLenum zpass);
56
57 extern void GLAPIENTRY
58 _mesa_StencilOp(GLenum fail, GLenum zfail, GLenum zpass);
59
60
61 extern void GLAPIENTRY
62 _mesa_ActiveStencilFaceEXT(GLenum face);
63
64 void GLAPIENTRY
65 _mesa_StencilOpSeparate_no_error(GLenum face, GLenum fail, GLenum zfail,
66 GLenum zpass);
67
68 extern void GLAPIENTRY
69 _mesa_StencilOpSeparate(GLenum face, GLenum fail, GLenum zfail, GLenum zpass);
70
71
72 void GLAPIENTRY
73 _mesa_StencilFuncSeparate_no_error(GLenum face, GLenum func, GLint ref,
74 GLuint mask);
75
76 extern void GLAPIENTRY
77 _mesa_StencilFuncSeparate(GLenum face, GLenum func, GLint ref, GLuint mask);
78
79
80 extern void GLAPIENTRY
81 _mesa_StencilFuncSeparateATI(GLenum frontfunc, GLenum backfunc, GLint ref, GLuint mask);
82
83 void GLAPIENTRY
84 _mesa_StencilMaskSeparate_no_error(GLenum face, GLuint mask);
85
86 extern void GLAPIENTRY
87 _mesa_StencilMaskSeparate(GLenum face, GLuint mask);
88
89 extern void
90 _mesa_init_stencil( struct gl_context * ctx );
91
92 /* From the GL 4.3 spec, 17.3.5:
93 * "Stencil comparison operations and queries of <ref> clamp its value
94 * to the range [0, 2^s-1], where <s> is the number of bits in the
95 * stencil buffer attached to the draw framebuffer."
96 */
97
98 static inline GLint
_mesa_get_stencil_ref(struct gl_context const * ctx,int face)99 _mesa_get_stencil_ref(struct gl_context const *ctx, int face)
100 {
101 GLint stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
102 GLint ref = ctx->Stencil.Ref[face];
103 return CLAMP(ref, 0, stencilMax);
104 }
105
106 static inline bool
_mesa_stencil_is_enabled(const struct gl_context * ctx)107 _mesa_stencil_is_enabled(const struct gl_context *ctx)
108 {
109 return ctx->Stencil.Enabled &&
110 ctx->DrawBuffer->Visual.stencilBits > 0;
111 }
112
113 static inline bool
_mesa_stencil_is_two_sided(const struct gl_context * ctx)114 _mesa_stencil_is_two_sided(const struct gl_context *ctx)
115 {
116 const int face = ctx->Stencil._BackFace;
117
118 return _mesa_stencil_is_enabled(ctx) &&
119 (ctx->Stencil.Function[0] != ctx->Stencil.Function[face] ||
120 ctx->Stencil.FailFunc[0] != ctx->Stencil.FailFunc[face] ||
121 ctx->Stencil.ZPassFunc[0] != ctx->Stencil.ZPassFunc[face] ||
122 ctx->Stencil.ZFailFunc[0] != ctx->Stencil.ZFailFunc[face] ||
123 ctx->Stencil.Ref[0] != ctx->Stencil.Ref[face] ||
124 ctx->Stencil.ValueMask[0] != ctx->Stencil.ValueMask[face] ||
125 ctx->Stencil.WriteMask[0] != ctx->Stencil.WriteMask[face]);
126 }
127
128 static inline bool
_mesa_stencil_is_write_enabled(const struct gl_context * ctx,bool is_two_sided)129 _mesa_stencil_is_write_enabled(const struct gl_context *ctx, bool is_two_sided)
130 {
131 return _mesa_stencil_is_enabled(ctx) &&
132 (ctx->Stencil.WriteMask[0] != 0 ||
133 (is_two_sided &&
134 ctx->Stencil.WriteMask[ctx->Stencil._BackFace] != 0));
135 }
136
137 #endif
138