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
  28 #include "context.h"
  29 #include "depth.h"
  30 #include "enums.h"
  31 #include "macros.h"
  32 #include "mtypes.h"
  33 #include "state.h"
  34
  35
  36 /**********************************************************************/
  37 /*****                          API Functions                     *****/
  38 /**********************************************************************/
  39
  40
  41
  42 void GLAPIENTRY
  43 _mesa_ClearDepth( GLclampd depth )
  44 {
  45    GET_CURRENT_CONTEXT(ctx);
  46
  47    if (MESA_VERBOSE & VERBOSE_API)
  48       _mesa_debug(ctx, "glClearDepth(%f)\n", depth);
  49
  50    ctx->Depth.Clear = CLAMP( depth, 0.0, 1.0 );
  51 }
  52
  53
  54 void GLAPIENTRY
  55 _mesa_ClearDepthf( GLclampf depth )
  56 {
  57    _mesa_ClearDepth(depth);
  58 }
  59
  60
  61 static ALWAYS_INLINE void
  62 depth_func(struct gl_context *ctx, GLenum func, bool no_error)
  63 {
  64    if (ctx->Depth.Func == func)
  65       return;
  66
  67    if (!no_error) {
  68       switch (func) {
  69       case GL_LESS:    /* (default) pass if incoming z < stored z */
  70       case GL_GEQUAL:
  71       case GL_LEQUAL:
  72       case GL_GREATER:
  73       case GL_NOTEQUAL:
  74       case GL_EQUAL:
  75       case GL_ALWAYS:
  76       case GL_NEVER:
  77          break;
  78       default:
  79          _mesa_error(ctx, GL_INVALID_ENUM, "glDepth.Func");
  80          return;
  81       }
  82    }
  83
  84    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewDepth ? 0 : _NEW_DEPTH);
  85    ctx->NewDriverState |= ctx->DriverFlags.NewDepth;
  86    ctx->Depth.Func = func;
  87    _mesa_update_allow_draw_out_of_order(ctx);
  88
  89    if (ctx->Driver.DepthFunc)
  90       ctx->Driver.DepthFunc(ctx, func);
  91 }
  92
  93
  94 void GLAPIENTRY
  95 _mesa_DepthFunc_no_error(GLenum func)
  96 {
  97    GET_CURRENT_CONTEXT(ctx);
  98    depth_func(ctx, func, true);
  99 }
 100
 101
 102 void GLAPIENTRY
 103 _mesa_DepthFunc(GLenum func)
 104 {
 105    GET_CURRENT_CONTEXT(ctx);
 106
 107    if (MESA_VERBOSE & VERBOSE_API)
 108       _mesa_debug(ctx, "glDepthFunc %s\n", _mesa_enum_to_string(func));
 109
 110    depth_func(ctx, func, false);
 111 }
 112
 113
 114
 115 void GLAPIENTRY
 116 _mesa_DepthMask( GLboolean flag )
 117 {
 118    GET_CURRENT_CONTEXT(ctx);
 119
 120    if (MESA_VERBOSE & VERBOSE_API)
 121       _mesa_debug(ctx, "glDepthMask %d\n", flag);
 122
 123    /*
 124     * GL_TRUE indicates depth buffer writing is enabled (default)
 125     * GL_FALSE indicates depth buffer writing is disabled
 126     */
 127    if (ctx->Depth.Mask == flag)
 128       return;
 129
 130    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewDepth ? 0 : _NEW_DEPTH);
 131    ctx->NewDriverState |= ctx->DriverFlags.NewDepth;
 132    ctx->Depth.Mask = flag;
 133    _mesa_update_allow_draw_out_of_order(ctx);
 134
 135    if (ctx->Driver.DepthMask)
 136       ctx->Driver.DepthMask( ctx, flag );
 137 }
 138
 139
 140
 141 /**
 142  * Specified by the GL_EXT_depth_bounds_test extension.
 143  */
 144 void GLAPIENTRY
 145 _mesa_DepthBoundsEXT( GLclampd zmin, GLclampd zmax )
 146 {
 147    GET_CURRENT_CONTEXT(ctx);
 148
 149    if (MESA_VERBOSE & VERBOSE_API)
 150       _mesa_debug(ctx, "glDepthBounds(%f, %f)\n", zmin, zmax);
 151
 152    if (zmin > zmax) {
 153       _mesa_error(ctx, GL_INVALID_VALUE, "glDepthBoundsEXT(zmin > zmax)");
 154       return;
 155    }
 156
 157    zmin = CLAMP(zmin, 0.0, 1.0);
 158    zmax = CLAMP(zmax, 0.0, 1.0);
 159
 160    if (ctx->Depth.BoundsMin == zmin && ctx->Depth.BoundsMax == zmax)
 161       return;
 162
 163    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewDepth ? 0 : _NEW_DEPTH);
 164    ctx->NewDriverState |= ctx->DriverFlags.NewDepth;
 165    ctx->Depth.BoundsMin = (GLfloat) zmin;
 166    ctx->Depth.BoundsMax = (GLfloat) zmax;
 167 }
 168
 169
 170 /**********************************************************************/
 171 /*****                      Initialization                        *****/
 172 /**********************************************************************/
 173
 174
 175 /**
 176  * Initialize the depth buffer attribute group in the given context.
 177  */
 178 void
 179 _mesa_init_depth(struct gl_context *ctx)
 180 {
 181    ctx->Depth.Test = GL_FALSE;
 182    ctx->Depth.Clear = 1.0;
 183    ctx->Depth.Func = GL_LESS;
 184    ctx->Depth.Mask = GL_TRUE;
 185 }