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 void GLAPIENTRY 61 _mesa_DepthFunc( GLenum func ) 62 { 63 GET_CURRENT_CONTEXT(ctx); 64 65 if (MESA_VERBOSE & VERBOSE_API) 66 _mesa_debug(ctx, "glDepthFunc %s\n", _mesa_enum_to_string(func)); 67 68 if (ctx->Depth.Func == func) 69 return; 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 FLUSH_VERTICES(ctx, _NEW_DEPTH); 87 ctx->Depth.Func = func; 88 89 if (ctx->Driver.DepthFunc) 90 ctx->Driver.DepthFunc( ctx, func ); 91 } 92 93 94 95 void GLAPIENTRY 96 _mesa_DepthMask( GLboolean flag ) 97 { 98 GET_CURRENT_CONTEXT(ctx); 99 100 if (MESA_VERBOSE & VERBOSE_API) 101 _mesa_debug(ctx, "glDepthMask %d\n", flag); 102 103 /* 104 * GL_TRUE indicates depth buffer writing is enabled (default) 105 * GL_FALSE indicates depth buffer writing is disabled 106 */ 107 if (ctx->Depth.Mask == flag) 108 return; 109 110 FLUSH_VERTICES(ctx, _NEW_DEPTH); 111 ctx->Depth.Mask = flag; 112 113 if (ctx->Driver.DepthMask) 114 ctx->Driver.DepthMask( ctx, flag ); 115 } 116 117 118 119 /** 120 * Specified by the GL_EXT_depth_bounds_test extension. 121 */ 122 void GLAPIENTRY 123 _mesa_DepthBoundsEXT( GLclampd zmin, GLclampd zmax ) 124 { 125 GET_CURRENT_CONTEXT(ctx); 126 127 if (MESA_VERBOSE & VERBOSE_API) 128 _mesa_debug(ctx, "glDepthBounds(%f, %f)\n", zmin, zmax); 129 130 if (zmin > zmax) { 131 _mesa_error(ctx, GL_INVALID_VALUE, "glDepthBoundsEXT(zmin > zmax)"); 132 return; 133 } 134 135 zmin = CLAMP(zmin, 0.0, 1.0); 136 zmax = CLAMP(zmax, 0.0, 1.0); 137 138 if (ctx->Depth.BoundsMin == zmin && ctx->Depth.BoundsMax == zmax) 139 return; 140 141 FLUSH_VERTICES(ctx, _NEW_DEPTH); 142 ctx->Depth.BoundsMin = (GLfloat) zmin; 143 ctx->Depth.BoundsMax = (GLfloat) zmax; 144 } 145 146 147 /**********************************************************************/ 148 /***** Initialization *****/ 149 /**********************************************************************/ 150 151 152 /** 153 * Initialize the depth buffer attribute group in the given context. 154 */ 155 void 156 _mesa_init_depth(struct gl_context *ctx) 157 { 158 ctx->Depth.Test = GL_FALSE; 159 ctx->Depth.Clear = 1.0; 160 ctx->Depth.Func = GL_LESS; 161 ctx->Depth.Mask = GL_TRUE; 162 } 163