src/mesa/main/stencil.h

   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
  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
 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
 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
 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