reactos/dll/opengl/mesa/main/depth.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.1
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 #include "glheader.h"
  27 #include "imports.h"
  28 #include "context.h"
  29 #include "depth.h"
  30 #include "enums.h"
  31 #include "macros.h"
  32 #include "mtypes.h"
  33
  34
  35 /**********************************************************************/
  36 /*****                          API Functions                     *****/
  37 /**********************************************************************/
  38
  39
  40
  41 void GLAPIENTRY
  42 _mesa_ClearDepth( GLclampd depth )
  43 {
  44    GET_CURRENT_CONTEXT(ctx);
  45    ASSERT_OUTSIDE_BEGIN_END(ctx);
  46
  47    if (MESA_VERBOSE & VERBOSE_API)
  48       _mesa_debug(ctx, "glClearDepth(%f)\n", depth);
  49
  50    depth = CLAMP( depth, 0.0, 1.0 );
  51
  52    if (ctx->Depth.Clear == depth)
  53       return;
  54
  55    FLUSH_VERTICES(ctx, _NEW_DEPTH);
  56    ctx->Depth.Clear = depth;
  57    if (ctx->Driver.ClearDepth)
  58       (*ctx->Driver.ClearDepth)( ctx, ctx->Depth.Clear );
  59 }
  60
  61
  62 void GLAPIENTRY
  63 _mesa_DepthFunc( GLenum func )
  64 {
  65    GET_CURRENT_CONTEXT(ctx);
  66    ASSERT_OUTSIDE_BEGIN_END(ctx);
  67
  68    if (MESA_VERBOSE & VERBOSE_API)
  69       _mesa_debug(ctx, "glDepthFunc %s\n", _mesa_lookup_enum_by_nr(func));
  70
  71    switch (func) {
  72    case GL_LESS:    /* (default) pass if incoming z < stored z */
  73    case GL_GEQUAL:
  74    case GL_LEQUAL:
  75    case GL_GREATER:
  76    case GL_NOTEQUAL:
  77    case GL_EQUAL:
  78    case GL_ALWAYS:
  79    case GL_NEVER:
  80       break;
  81    default:
  82       _mesa_error( ctx, GL_INVALID_ENUM, "glDepth.Func" );
  83       return;
  84    }
  85
  86    if (ctx->Depth.Func == func)
  87       return;
  88
  89    FLUSH_VERTICES(ctx, _NEW_DEPTH);
  90    ctx->Depth.Func = func;
  91
  92    if (ctx->Driver.DepthFunc)
  93       ctx->Driver.DepthFunc( ctx, func );
  94 }
  95
  96
  97
  98 void GLAPIENTRY
  99 _mesa_DepthMask( GLboolean flag )
 100 {
 101    GET_CURRENT_CONTEXT(ctx);
 102    ASSERT_OUTSIDE_BEGIN_END(ctx);
 103
 104    if (MESA_VERBOSE & VERBOSE_API)
 105       _mesa_debug(ctx, "glDepthMask %d\n", flag);
 106
 107    /*
 108     * GL_TRUE indicates depth buffer writing is enabled (default)
 109     * GL_FALSE indicates depth buffer writing is disabled
 110     */
 111    if (ctx->Depth.Mask == flag)
 112       return;
 113
 114    FLUSH_VERTICES(ctx, _NEW_DEPTH);
 115    ctx->Depth.Mask = flag;
 116
 117    if (ctx->Driver.DepthMask)
 118       ctx->Driver.DepthMask( ctx, flag );
 119 }
 120
 121
 122
 123 /**
 124  * Specified by the GL_EXT_depth_bounds_test extension.
 125  */
 126 void GLAPIENTRY
 127 _mesa_DepthBoundsEXT( GLclampd zmin, GLclampd zmax )
 128 {
 129    GET_CURRENT_CONTEXT(ctx);
 130    ASSERT_OUTSIDE_BEGIN_END(ctx);
 131
 132    if (MESA_VERBOSE & VERBOSE_API)
 133       _mesa_debug(ctx, "glDepthBounds(%f, %f)\n", zmin, zmax);
 134
 135    if (zmin > zmax) {
 136       _mesa_error(ctx, GL_INVALID_VALUE, "glDepthBoundsEXT(zmin > zmax)");
 137       return;
 138    }
 139
 140    zmin = CLAMP(zmin, 0.0, 1.0);
 141    zmax = CLAMP(zmax, 0.0, 1.0);
 142
 143    if (ctx->Depth.BoundsMin == zmin && ctx->Depth.BoundsMax == zmax)
 144       return;
 145
 146    FLUSH_VERTICES(ctx, _NEW_DEPTH);
 147    ctx->Depth.BoundsMin = (GLfloat) zmin;
 148    ctx->Depth.BoundsMax = (GLfloat) zmax;
 149 }
 150
 151
 152 /**********************************************************************/
 153 /*****                      Initialization                        *****/
 154 /**********************************************************************/
 155
 156
 157 /**
 158  * Initialize the depth buffer attribute group in the given context.
 159  */
 160 void
 161 _mesa_init_depth(struct gl_context *ctx)
 162 {
 163    ctx->Depth.Test = GL_FALSE;
 164    ctx->Depth.Clear = 1.0;
 165    ctx->Depth.Func = GL_LESS;
 166    ctx->Depth.Mask = GL_TRUE;
 167 }