src/mesa/main/depth.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * 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
  46    if (MESA_VERBOSE & VERBOSE_API)
  47       _mesa_debug(ctx, "glClearDepth(%f)\n", depth);
  48
  49    ctx->Depth.Clear = CLAMP( depth, 0.0, 1.0 );
  50 }
  51
  52
  53 void GLAPIENTRY
  54 _mesa_ClearDepthf( GLclampf depth )
  55 {
  56    _mesa_ClearDepth(depth);
  57 }
  58
  59
  60 static ALWAYS_INLINE void
  61 depth_func(struct gl_context *ctx, GLenum func, bool no_error)
  62 {
  63    if (ctx->Depth.Func == func)
  64       return;
  65
  66    if (!no_error) {
  67       switch (func) {
  68       case GL_LESS:    /* (default) pass if incoming z < stored z */
  69       case GL_GEQUAL:
  70       case GL_LEQUAL:
  71       case GL_GREATER:
  72       case GL_NOTEQUAL:
  73       case GL_EQUAL:
  74       case GL_ALWAYS:
  75       case GL_NEVER:
  76          break;
  77       default:
  78          _mesa_error(ctx, GL_INVALID_ENUM, "glDepth.Func");
  79          return;
  80       }
  81    }
  82
  83    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewDepth ? 0 : _NEW_DEPTH);
  84    ctx->NewDriverState |= ctx->DriverFlags.NewDepth;
  85    ctx->Depth.Func = func;
  86
  87    if (ctx->Driver.DepthFunc)
  88       ctx->Driver.DepthFunc(ctx, func);
  89 }
  90
  91
  92 void GLAPIENTRY
  93 _mesa_DepthFunc_no_error(GLenum func)
  94 {
  95    GET_CURRENT_CONTEXT(ctx);
  96    depth_func(ctx, func, true);
  97 }
  98
  99
 100 void GLAPIENTRY
 101 _mesa_DepthFunc(GLenum func)
 102 {
 103    GET_CURRENT_CONTEXT(ctx);
 104
 105    if (MESA_VERBOSE & VERBOSE_API)
 106       _mesa_debug(ctx, "glDepthFunc %s\n", _mesa_enum_to_string(func));
 107
 108    depth_func(ctx, func, false);
 109 }
 110
 111
 112
 113 void GLAPIENTRY
 114 _mesa_DepthMask( GLboolean flag )
 115 {
 116    GET_CURRENT_CONTEXT(ctx);
 117
 118    if (MESA_VERBOSE & VERBOSE_API)
 119       _mesa_debug(ctx, "glDepthMask %d\n", flag);
 120
 121    /*
 122     * GL_TRUE indicates depth buffer writing is enabled (default)
 123     * GL_FALSE indicates depth buffer writing is disabled
 124     */
 125    if (ctx->Depth.Mask == flag)
 126       return;
 127
 128    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewDepth ? 0 : _NEW_DEPTH);
 129    ctx->NewDriverState |= ctx->DriverFlags.NewDepth;
 130    ctx->Depth.Mask = flag;
 131
 132    if (ctx->Driver.DepthMask)
 133       ctx->Driver.DepthMask( ctx, flag );
 134 }
 135
 136
 137
 138 /**
 139  * Specified by the GL_EXT_depth_bounds_test extension.
 140  */
 141 void GLAPIENTRY
 142 _mesa_DepthBoundsEXT( GLclampd zmin, GLclampd zmax )
 143 {
 144    GET_CURRENT_CONTEXT(ctx);
 145
 146    if (MESA_VERBOSE & VERBOSE_API)
 147       _mesa_debug(ctx, "glDepthBounds(%f, %f)\n", zmin, zmax);
 148
 149    if (zmin > zmax) {
 150       _mesa_error(ctx, GL_INVALID_VALUE, "glDepthBoundsEXT(zmin > zmax)");
 151       return;
 152    }
 153
 154    zmin = CLAMP(zmin, 0.0, 1.0);
 155    zmax = CLAMP(zmax, 0.0, 1.0);
 156
 157    if (ctx->Depth.BoundsMin == zmin && ctx->Depth.BoundsMax == zmax)
 158       return;
 159
 160    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewDepth ? 0 : _NEW_DEPTH);
 161    ctx->NewDriverState |= ctx->DriverFlags.NewDepth;
 162    ctx->Depth.BoundsMin = (GLfloat) zmin;
 163    ctx->Depth.BoundsMax = (GLfloat) zmax;
 164 }
 165
 166
 167 /**********************************************************************/
 168 /*****                      Initialization                        *****/
 169 /**********************************************************************/
 170
 171
 172 /**
 173  * Initialize the depth buffer attribute group in the given context.
 174  */
 175 void
 176 _mesa_init_depth(struct gl_context *ctx)
 177 {
 178    ctx->Depth.Test = GL_FALSE;
 179    ctx->Depth.Clear = 1.0;
 180    ctx->Depth.Func = GL_LESS;
 181    ctx->Depth.Mask = GL_TRUE;
 182 }