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

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 2010  VMware, Inc.  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 BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  20  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 #include <precomp.h>
  25
  26 #include "git_sha1.h"
  27
  28 /**
  29  * Override the context's GL version if the environment variable
  30  * MESA_GL_VERSION_OVERRIDE is set. Valid values of MESA_GL_VERSION_OVERRIDE
  31  * are point-separated version numbers, such as "3.0".
  32  */
  33 static void
  34 override_version(struct gl_context *ctx, GLuint *major, GLuint *minor)
  35 {
  36    const char *env_var = "MESA_GL_VERSION_OVERRIDE";
  37    const char *version;
  38    int n;
  39
  40    version = getenv(env_var);
  41    if (!version) {
  42       return;
  43    }
  44
  45    n = sscanf(version, "%u.%u", major, minor);
  46    if (n != 2) {
  47       fprintf(stderr, "error: invalid value for %s: %s\n", env_var, version);
  48       return;
  49    }
  50 }
  51
  52 /**
  53  * Examine enabled GL extensions to determine GL version.
  54  * Return major and minor version numbers.
  55  */
  56 static void
  57 compute_version(struct gl_context *ctx)
  58 {
  59    GLuint major, minor;
  60    static const int max = 100;
  61
  62    const GLboolean ver_1_3 = (ctx->Extensions.ARB_texture_cube_map &&
  63                               ctx->Extensions.ARB_texture_env_combine &&
  64                               ctx->Extensions.ARB_texture_env_dot3);
  65    const GLboolean ver_1_4 = (ver_1_3 &&
  66                               ctx->Extensions.ARB_texture_env_crossbar &&
  67                               ctx->Extensions.ARB_window_pos &&
  68                               ctx->Extensions.EXT_blend_color &&
  69                               ctx->Extensions.EXT_blend_func_separate &&
  70                               ctx->Extensions.EXT_blend_minmax &&
  71                               ctx->Extensions.EXT_fog_coord &&
  72                               ctx->Extensions.EXT_point_parameters &&
  73                               ctx->Extensions.EXT_secondary_color);
  74    const GLboolean ver_1_5 = (ver_1_4 &&
  75                               ctx->Extensions.EXT_shadow_funcs);
  76    const GLboolean ver_2_0 = (ver_1_5 &&
  77                               ctx->Extensions.ARB_point_sprite &&
  78                               ctx->Extensions.ARB_texture_non_power_of_two &&
  79                               ctx->Extensions.EXT_blend_equation_separate);
  80    const GLboolean ver_2_1 = (ver_2_0);
  81    const GLboolean ver_3_0 = (ver_2_1 &&
  82                               ctx->Extensions.ARB_half_float_pixel &&
  83                               ctx->Extensions.ARB_half_float_vertex &&
  84                               ctx->Extensions.ARB_map_buffer_range &&
  85                               ctx->Extensions.ARB_texture_float &&
  86                               ctx->Extensions.APPLE_vertex_array_object);
  87
  88
  89    if (ver_3_0) {
  90       major = 3;
  91       minor = 0;
  92    }
  93    else if (ver_2_1) {
  94       major = 2;
  95       minor = 1;
  96    }
  97    else if (ver_2_0) {
  98       major = 2;
  99       minor = 0;
 100    }
 101    else if (ver_1_5) {
 102       major = 1;
 103       minor = 5;
 104    }
 105    else if (ver_1_4) {
 106       major = 1;
 107       minor = 4;
 108    }
 109    else if (ver_1_3) {
 110       major = 1;
 111       minor = 3;
 112    }
 113    else {
 114       major = 1;
 115       minor = 2;
 116    }
 117
 118    ctx->VersionMajor = major;
 119    ctx->VersionMinor = minor;
 120
 121    override_version(ctx, &ctx->VersionMajor, &ctx->VersionMinor);
 122
 123    ctx->VersionString = (char *) malloc(max);
 124    if (ctx->VersionString) {
 125       _mesa_snprintf(ctx->VersionString, max,
 126                      "%u.%u Mesa " MESA_VERSION_STRING
 127 #ifdef MESA_GIT_SHA1
 128                      " (" MESA_GIT_SHA1 ")"
 129 #endif
 130                      ,
 131                      ctx->VersionMajor, ctx->VersionMinor);
 132    }
 133 }
 134
 135 /**
 136  * Set the context's VersionMajor, VersionMinor, VersionString fields.
 137  * This should only be called once as part of context initialization
 138  * or to perform version check for GLX_ARB_create_context_profile.
 139  */
 140 void
 141 _mesa_compute_version(struct gl_context *ctx)
 142 {
 143    if (ctx->VersionMajor)
 144       return;
 145
 146    compute_version(ctx);
 147 }