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
_mesa_ClearDepth(GLclampd depth)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 }
58 
59 
60 void GLAPIENTRY
_mesa_ClearDepthf(GLclampf depth)61 _mesa_ClearDepthf( GLclampf depth )
62 {
63    _mesa_ClearDepth(depth);
64 }
65 
66 
67 void GLAPIENTRY
_mesa_DepthFunc(GLenum func)68 _mesa_DepthFunc( GLenum func )
69 {
70    GET_CURRENT_CONTEXT(ctx);
71    ASSERT_OUTSIDE_BEGIN_END(ctx);
72 
73    if (MESA_VERBOSE & VERBOSE_API)
74       _mesa_debug(ctx, "glDepthFunc %s\n", _mesa_lookup_enum_by_nr(func));
75 
76    switch (func) {
77    case GL_LESS:    /* (default) pass if incoming z < stored z */
78    case GL_GEQUAL:
79    case GL_LEQUAL:
80    case GL_GREATER:
81    case GL_NOTEQUAL:
82    case GL_EQUAL:
83    case GL_ALWAYS:
84    case GL_NEVER:
85       break;
86    default:
87       _mesa_error( ctx, GL_INVALID_ENUM, "glDepth.Func" );
88       return;
89    }
90 
91    if (ctx->Depth.Func == func)
92       return;
93 
94    FLUSH_VERTICES(ctx, _NEW_DEPTH);
95    ctx->Depth.Func = func;
96 
97    if (ctx->Driver.DepthFunc)
98       ctx->Driver.DepthFunc( ctx, func );
99 }
100 
101 
102 
103 void GLAPIENTRY
_mesa_DepthMask(GLboolean flag)104 _mesa_DepthMask( GLboolean flag )
105 {
106    GET_CURRENT_CONTEXT(ctx);
107    ASSERT_OUTSIDE_BEGIN_END(ctx);
108 
109    if (MESA_VERBOSE & VERBOSE_API)
110       _mesa_debug(ctx, "glDepthMask %d\n", flag);
111 
112    /*
113     * GL_TRUE indicates depth buffer writing is enabled (default)
114     * GL_FALSE indicates depth buffer writing is disabled
115     */
116    if (ctx->Depth.Mask == flag)
117       return;
118 
119    FLUSH_VERTICES(ctx, _NEW_DEPTH);
120    ctx->Depth.Mask = flag;
121 
122    if (ctx->Driver.DepthMask)
123       ctx->Driver.DepthMask( ctx, flag );
124 }
125 
126 
127 
128 /**
129  * Specified by the GL_EXT_depth_bounds_test extension.
130  */
131 void GLAPIENTRY
_mesa_DepthBoundsEXT(GLclampd zmin,GLclampd zmax)132 _mesa_DepthBoundsEXT( GLclampd zmin, GLclampd zmax )
133 {
134    GET_CURRENT_CONTEXT(ctx);
135    ASSERT_OUTSIDE_BEGIN_END(ctx);
136 
137    if (MESA_VERBOSE & VERBOSE_API)
138       _mesa_debug(ctx, "glDepthBounds(%f, %f)\n", zmin, zmax);
139 
140    if (zmin > zmax) {
141       _mesa_error(ctx, GL_INVALID_VALUE, "glDepthBoundsEXT(zmin > zmax)");
142       return;
143    }
144 
145    zmin = CLAMP(zmin, 0.0, 1.0);
146    zmax = CLAMP(zmax, 0.0, 1.0);
147 
148    if (ctx->Depth.BoundsMin == zmin && ctx->Depth.BoundsMax == zmax)
149       return;
150 
151    FLUSH_VERTICES(ctx, _NEW_DEPTH);
152    ctx->Depth.BoundsMin = (GLfloat) zmin;
153    ctx->Depth.BoundsMax = (GLfloat) zmax;
154 }
155 
156 
157 /**********************************************************************/
158 /*****                      Initialization                        *****/
159 /**********************************************************************/
160 
161 
162 /**
163  * Initialize the depth buffer attribute group in the given context.
164  */
165 void
_mesa_init_depth(struct gl_context * ctx)166 _mesa_init_depth(struct gl_context *ctx)
167 {
168    ctx->Depth.Test = GL_FALSE;
169    ctx->Depth.Clear = 1.0;
170    ctx->Depth.Func = GL_LESS;
171    ctx->Depth.Mask = GL_TRUE;
172 }
173