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main/extensions: Build list of extensions that can't be disabled
[mesa.git] / src / mesa / main / extensions.c
1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
5 * Copyright (C) 2009 VMware, Inc. 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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27 /**
28 * \file
29 * \brief Extension handling
30 */
31
32
33 #include "glheader.h"
34 #include "imports.h"
35 #include "context.h"
36 #include "extensions.h"
37 #include "macros.h"
38 #include "mtypes.h"
39
40 struct gl_extensions _mesa_extension_override_enables;
41 struct gl_extensions _mesa_extension_override_disables;
42 static char *extra_extensions = NULL;
43 static char *cant_disable_extensions = NULL;
44
45 enum {
46 DISABLE = 0,
47 GLL = 1 << API_OPENGL_COMPAT, /* GL Legacy / Compatibility */
48 GLC = 1 << API_OPENGL_CORE, /* GL Core */
49 GL = (1 << API_OPENGL_COMPAT) | (1 << API_OPENGL_CORE),
50 ES1 = 1 << API_OPENGLES,
51 ES2 = 1 << API_OPENGLES2,
52 ES3 = 1 << (API_OPENGL_LAST + 1),
53 };
54
55 /**
56 * \brief An element of the \c extension_table.
57 */
58 struct extension {
59 /** Name of extension, such as "GL_ARB_depth_clamp". */
60 const char *name;
61
62 /** Offset (in bytes) of the corresponding member in struct gl_extensions. */
63 size_t offset;
64
65 /** Set of API's in which the extension exists, as a bitset. */
66 uint8_t api_set;
67
68 /** Year the extension was proposed or approved. Used to sort the
69 * extension string chronologically. */
70 uint16_t year;
71 };
72
73
74 /**
75 * Given a member \c x of struct gl_extensions, return offset of
76 * \c x in bytes.
77 */
78 #define o(x) offsetof(struct gl_extensions, x)
79
80
81 /**
82 * \brief Table of supported OpenGL extensions for all API's.
83 */
84 static const struct extension extension_table[] = {
85 /* ARB Extensions */
86 { "GL_ARB_ES2_compatibility", o(ARB_ES2_compatibility), GL, 2009 },
87 { "GL_ARB_ES3_compatibility", o(ARB_ES3_compatibility), GL, 2012 },
88 { "GL_ARB_arrays_of_arrays", o(ARB_arrays_of_arrays), GL, 2012 },
89 { "GL_ARB_base_instance", o(ARB_base_instance), GL, 2011 },
90 { "GL_ARB_blend_func_extended", o(ARB_blend_func_extended), GL, 2009 },
91 { "GL_ARB_buffer_storage", o(ARB_buffer_storage), GL, 2013 },
92 { "GL_ARB_clear_buffer_object", o(dummy_true), GL, 2012 },
93 { "GL_ARB_color_buffer_float", o(ARB_color_buffer_float), GL, 2004 },
94 { "GL_ARB_compressed_texture_pixel_storage", o(dummy_true), GL, 2011 },
95 { "GL_ARB_compute_shader", o(ARB_compute_shader), GL, 2012 },
96 { "GL_ARB_copy_buffer", o(dummy_true), GL, 2008 },
97 { "GL_ARB_conservative_depth", o(ARB_conservative_depth), GL, 2011 },
98 { "GL_ARB_debug_output", o(dummy_true), GL, 2009 },
99 { "GL_ARB_depth_buffer_float", o(ARB_depth_buffer_float), GL, 2008 },
100 { "GL_ARB_depth_clamp", o(ARB_depth_clamp), GL, 2003 },
101 { "GL_ARB_depth_texture", o(ARB_depth_texture), GLL, 2001 },
102 { "GL_ARB_draw_buffers", o(dummy_true), GL, 2002 },
103 { "GL_ARB_draw_buffers_blend", o(ARB_draw_buffers_blend), GL, 2009 },
104 { "GL_ARB_draw_elements_base_vertex", o(ARB_draw_elements_base_vertex), GL, 2009 },
105 { "GL_ARB_draw_indirect", o(ARB_draw_indirect), GLC, 2010 },
106 { "GL_ARB_draw_instanced", o(ARB_draw_instanced), GL, 2008 },
107 { "GL_ARB_explicit_attrib_location", o(ARB_explicit_attrib_location), GL, 2009 },
108 { "GL_ARB_explicit_uniform_location", o(ARB_explicit_uniform_location), GL, 2012 },
109 { "GL_ARB_fragment_coord_conventions", o(ARB_fragment_coord_conventions), GL, 2009 },
110 { "GL_ARB_fragment_program", o(ARB_fragment_program), GLL, 2002 },
111 { "GL_ARB_fragment_program_shadow", o(ARB_fragment_program_shadow), GLL, 2003 },
112 { "GL_ARB_fragment_shader", o(ARB_fragment_shader), GL, 2002 },
113 { "GL_ARB_framebuffer_object", o(ARB_framebuffer_object), GL, 2005 },
114 { "GL_ARB_framebuffer_sRGB", o(EXT_framebuffer_sRGB), GL, 1998 },
115 { "GL_ARB_get_program_binary", o(dummy_true), GL, 2010 },
116 { "GL_ARB_gpu_shader5", o(ARB_gpu_shader5), GL, 2010 },
117 { "GL_ARB_half_float_pixel", o(dummy_true), GL, 2003 },
118 { "GL_ARB_half_float_vertex", o(ARB_half_float_vertex), GL, 2008 },
119 { "GL_ARB_instanced_arrays", o(ARB_instanced_arrays), GL, 2008 },
120 { "GL_ARB_internalformat_query", o(ARB_internalformat_query), GL, 2011 },
121 { "GL_ARB_invalidate_subdata", o(dummy_true), GL, 2012 },
122 { "GL_ARB_map_buffer_alignment", o(dummy_true), GL, 2011 },
123 { "GL_ARB_map_buffer_range", o(ARB_map_buffer_range), GL, 2008 },
124 { "GL_ARB_multi_bind", o(dummy_true), GL, 2013 },
125 { "GL_ARB_multi_draw_indirect", o(ARB_draw_indirect), GLC, 2012 },
126 { "GL_ARB_multisample", o(dummy_true), GLL, 1994 },
127 { "GL_ARB_multitexture", o(dummy_true), GLL, 1998 },
128 { "GL_ARB_occlusion_query2", o(ARB_occlusion_query2), GL, 2003 },
129 { "GL_ARB_occlusion_query", o(ARB_occlusion_query), GLL, 2001 },
130 { "GL_ARB_pixel_buffer_object", o(EXT_pixel_buffer_object), GL, 2004 },
131 { "GL_ARB_point_parameters", o(EXT_point_parameters), GLL, 1997 },
132 { "GL_ARB_point_sprite", o(ARB_point_sprite), GL, 2003 },
133 { "GL_ARB_provoking_vertex", o(EXT_provoking_vertex), GL, 2009 },
134 { "GL_ARB_robustness", o(dummy_true), GL, 2010 },
135 { "GL_ARB_sample_shading", o(ARB_sample_shading), GL, 2009 },
136 { "GL_ARB_sampler_objects", o(dummy_true), GL, 2009 },
137 { "GL_ARB_seamless_cube_map", o(ARB_seamless_cube_map), GL, 2009 },
138 { "GL_ARB_separate_shader_objects", o(dummy_true), GL, 2010 },
139 { "GL_ARB_shader_atomic_counters", o(ARB_shader_atomic_counters), GL, 2011 },
140 { "GL_ARB_shader_bit_encoding", o(ARB_shader_bit_encoding), GL, 2010 },
141 { "GL_ARB_shader_image_load_store", o(ARB_shader_image_load_store), GL, 2011 },
142 { "GL_ARB_shader_objects", o(dummy_true), GL, 2002 },
143 { "GL_ARB_shader_stencil_export", o(ARB_shader_stencil_export), GL, 2009 },
144 { "GL_ARB_shader_texture_lod", o(ARB_shader_texture_lod), GL, 2009 },
145 { "GL_ARB_shading_language_100", o(dummy_true), GLL, 2003 },
146 { "GL_ARB_shading_language_packing", o(ARB_shading_language_packing), GL, 2011 },
147 { "GL_ARB_shading_language_420pack", o(ARB_shading_language_420pack), GL, 2011 },
148 { "GL_ARB_shadow", o(ARB_shadow), GLL, 2001 },
149 { "GL_ARB_stencil_texturing", o(ARB_stencil_texturing), GL, 2012 },
150 { "GL_ARB_sync", o(ARB_sync), GL, 2003 },
151 { "GL_ARB_texture_border_clamp", o(ARB_texture_border_clamp), GLL, 2000 },
152 { "GL_ARB_texture_buffer_object", o(ARB_texture_buffer_object), GLC, 2008 },
153 { "GL_ARB_texture_buffer_object_rgb32", o(ARB_texture_buffer_object_rgb32), GLC, 2009 },
154 { "GL_ARB_texture_buffer_range", o(ARB_texture_buffer_range), GLC, 2012 },
155 { "GL_ARB_texture_compression", o(dummy_true), GLL, 2000 },
156 { "GL_ARB_texture_compression_rgtc", o(ARB_texture_compression_rgtc), GL, 2004 },
157 { "GL_ARB_texture_cube_map", o(ARB_texture_cube_map), GLL, 1999 },
158 { "GL_ARB_texture_cube_map_array", o(ARB_texture_cube_map_array), GL, 2009 },
159 { "GL_ARB_texture_env_add", o(dummy_true), GLL, 1999 },
160 { "GL_ARB_texture_env_combine", o(ARB_texture_env_combine), GLL, 2001 },
161 { "GL_ARB_texture_env_crossbar", o(ARB_texture_env_crossbar), GLL, 2001 },
162 { "GL_ARB_texture_env_dot3", o(ARB_texture_env_dot3), GLL, 2001 },
163 { "GL_ARB_texture_float", o(ARB_texture_float), GL, 2004 },
164 { "GL_ARB_texture_gather", o(ARB_texture_gather), GL, 2009 },
165 { "GL_ARB_texture_mirrored_repeat", o(dummy_true), GLL, 2001 },
166 { "GL_ARB_texture_mirror_clamp_to_edge", o(ARB_texture_mirror_clamp_to_edge), GL, 2013 },
167 { "GL_ARB_texture_multisample", o(ARB_texture_multisample), GL, 2009 },
168 { "GL_ARB_texture_non_power_of_two", o(ARB_texture_non_power_of_two), GL, 2003 },
169 { "GL_ARB_texture_query_levels", o(ARB_texture_query_levels), GL, 2012 },
170 { "GL_ARB_texture_query_lod", o(ARB_texture_query_lod), GL, 2009 },
171 { "GL_ARB_texture_rectangle", o(NV_texture_rectangle), GL, 2004 },
172 { "GL_ARB_texture_rgb10_a2ui", o(ARB_texture_rgb10_a2ui), GL, 2009 },
173 { "GL_ARB_texture_rg", o(ARB_texture_rg), GL, 2008 },
174 { "GL_ARB_texture_storage", o(dummy_true), GL, 2011 },
175 { "GL_ARB_texture_storage_multisample", o(ARB_texture_multisample), GL, 2012 },
176 { "GL_ARB_texture_view", o(ARB_texture_view), GL, 2012 },
177 { "GL_ARB_texture_swizzle", o(EXT_texture_swizzle), GL, 2008 },
178 { "GL_ARB_timer_query", o(ARB_timer_query), GL, 2010 },
179 { "GL_ARB_transform_feedback2", o(ARB_transform_feedback2), GL, 2010 },
180 { "GL_ARB_transform_feedback3", o(ARB_transform_feedback3), GL, 2010 },
181 { "GL_ARB_transform_feedback_instanced", o(ARB_transform_feedback_instanced), GL, 2011 },
182 { "GL_ARB_transpose_matrix", o(dummy_true), GLL, 1999 },
183 { "GL_ARB_uniform_buffer_object", o(ARB_uniform_buffer_object), GL, 2009 },
184 { "GL_ARB_vertex_array_bgra", o(EXT_vertex_array_bgra), GL, 2008 },
185 { "GL_ARB_vertex_array_object", o(dummy_true), GL, 2006 },
186 { "GL_ARB_vertex_attrib_binding", o(dummy_true), GL, 2012 },
187 { "GL_ARB_vertex_buffer_object", o(dummy_true), GLL, 2003 },
188 { "GL_ARB_vertex_program", o(ARB_vertex_program), GLL, 2002 },
189 { "GL_ARB_vertex_shader", o(ARB_vertex_shader), GL, 2002 },
190 { "GL_ARB_vertex_type_10f_11f_11f_rev", o(ARB_vertex_type_10f_11f_11f_rev), GL, 2013 },
191 { "GL_ARB_vertex_type_2_10_10_10_rev", o(ARB_vertex_type_2_10_10_10_rev), GL, 2009 },
192 { "GL_ARB_viewport_array", o(ARB_viewport_array), GLC, 2010 },
193 { "GL_ARB_window_pos", o(dummy_true), GLL, 2001 },
194 /* EXT extensions */
195 { "GL_EXT_abgr", o(dummy_true), GL, 1995 },
196 { "GL_EXT_bgra", o(dummy_true), GLL, 1995 },
197 { "GL_EXT_blend_color", o(EXT_blend_color), GLL, 1995 },
198 { "GL_EXT_blend_equation_separate", o(EXT_blend_equation_separate), GL, 2003 },
199 { "GL_EXT_blend_func_separate", o(EXT_blend_func_separate), GLL, 1999 },
200 { "GL_EXT_discard_framebuffer", o(dummy_true), ES1 | ES2, 2009 },
201 { "GL_EXT_blend_minmax", o(EXT_blend_minmax), GLL | ES1 | ES2, 1995 },
202 { "GL_EXT_blend_subtract", o(dummy_true), GLL, 1995 },
203 { "GL_EXT_compiled_vertex_array", o(dummy_true), GLL, 1996 },
204 { "GL_EXT_copy_texture", o(dummy_true), GLL, 1995 },
205 { "GL_EXT_depth_bounds_test", o(EXT_depth_bounds_test), GL, 2002 },
206 { "GL_EXT_draw_buffers2", o(EXT_draw_buffers2), GL, 2006 },
207 { "GL_EXT_draw_instanced", o(ARB_draw_instanced), GL, 2006 },
208 { "GL_EXT_draw_range_elements", o(dummy_true), GLL, 1997 },
209 { "GL_EXT_fog_coord", o(dummy_true), GLL, 1999 },
210 { "GL_EXT_framebuffer_blit", o(dummy_true), GL, 2005 },
211 { "GL_EXT_framebuffer_multisample", o(EXT_framebuffer_multisample), GL, 2005 },
212 { "GL_EXT_framebuffer_multisample_blit_scaled", o(EXT_framebuffer_multisample_blit_scaled), GL, 2011 },
213 { "GL_EXT_framebuffer_object", o(dummy_true), GLL, 2000 },
214 { "GL_EXT_framebuffer_sRGB", o(EXT_framebuffer_sRGB), GL, 1998 },
215 { "GL_EXT_gpu_program_parameters", o(EXT_gpu_program_parameters), GLL, 2006 },
216 { "GL_EXT_gpu_shader4", o(EXT_gpu_shader4), GL, 2006 },
217 { "GL_EXT_map_buffer_range", o(ARB_map_buffer_range), ES1 | ES2, 2012 },
218 { "GL_EXT_multi_draw_arrays", o(dummy_true), GLL | ES1 | ES2, 1999 },
219 { "GL_EXT_packed_depth_stencil", o(dummy_true), GL, 2005 },
220 { "GL_EXT_packed_float", o(EXT_packed_float), GL, 2004 },
221 { "GL_EXT_packed_pixels", o(dummy_true), GLL, 1997 },
222 { "GL_EXT_pixel_buffer_object", o(EXT_pixel_buffer_object), GL, 2004 },
223 { "GL_EXT_point_parameters", o(EXT_point_parameters), GLL, 1997 },
224 { "GL_EXT_polygon_offset", o(dummy_true), GLL, 1995 },
225 { "GL_EXT_provoking_vertex", o(EXT_provoking_vertex), GL, 2009 },
226 { "GL_EXT_rescale_normal", o(dummy_true), GLL, 1997 },
227 { "GL_EXT_secondary_color", o(dummy_true), GLL, 1999 },
228 { "GL_EXT_separate_shader_objects", o(dummy_true), ES2, 2013 },
229 { "GL_EXT_separate_specular_color", o(dummy_true), GLL, 1997 },
230 { "GL_EXT_shader_integer_mix", o(EXT_shader_integer_mix), GL | ES3, 2013 },
231 { "GL_EXT_shadow_funcs", o(ARB_shadow), GLL, 2002 },
232 { "GL_EXT_stencil_two_side", o(EXT_stencil_two_side), GLL, 2001 },
233 { "GL_EXT_stencil_wrap", o(dummy_true), GLL, 2002 },
234 { "GL_EXT_subtexture", o(dummy_true), GLL, 1995 },
235 { "GL_EXT_texture3D", o(EXT_texture3D), GLL, 1996 },
236 { "GL_EXT_texture_array", o(EXT_texture_array), GL, 2006 },
237 { "GL_EXT_texture_compression_dxt1", o(ANGLE_texture_compression_dxt), GL | ES1 | ES2, 2004 },
238 { "GL_ANGLE_texture_compression_dxt3", o(ANGLE_texture_compression_dxt), GL | ES1 | ES2, 2011 },
239 { "GL_ANGLE_texture_compression_dxt5", o(ANGLE_texture_compression_dxt), GL | ES1 | ES2, 2011 },
240 { "GL_EXT_texture_compression_latc", o(EXT_texture_compression_latc), GL, 2006 },
241 { "GL_EXT_texture_compression_rgtc", o(ARB_texture_compression_rgtc), GL, 2004 },
242 { "GL_EXT_texture_compression_s3tc", o(EXT_texture_compression_s3tc), GL, 2000 },
243 { "GL_EXT_texture_cube_map", o(ARB_texture_cube_map), GLL, 2001 },
244 { "GL_EXT_texture_edge_clamp", o(dummy_true), GLL, 1997 },
245 { "GL_EXT_texture_env_add", o(dummy_true), GLL, 1999 },
246 { "GL_EXT_texture_env_combine", o(dummy_true), GLL, 2000 },
247 { "GL_EXT_texture_env_dot3", o(EXT_texture_env_dot3), GLL, 2000 },
248 { "GL_EXT_texture_filter_anisotropic", o(EXT_texture_filter_anisotropic), GL | ES1 | ES2, 1999 },
249 { "GL_EXT_texture_format_BGRA8888", o(dummy_true), ES1 | ES2, 2005 },
250 { "GL_EXT_texture_rg", o(ARB_texture_rg), ES2, 2011 },
251 { "GL_EXT_read_format_bgra", o(dummy_true), ES1 | ES2, 2009 },
252 { "GL_EXT_texture_integer", o(EXT_texture_integer), GL, 2006 },
253 { "GL_EXT_texture_lod_bias", o(dummy_true), GLL | ES1, 1999 },
254 { "GL_EXT_texture_mirror_clamp", o(EXT_texture_mirror_clamp), GL, 2004 },
255 { "GL_EXT_texture_object", o(dummy_true), GLL, 1995 },
256 { "GL_EXT_texture", o(dummy_true), GLL, 1996 },
257 { "GL_EXT_texture_rectangle", o(NV_texture_rectangle), GLL, 2004 },
258 { "GL_EXT_texture_shared_exponent", o(EXT_texture_shared_exponent), GL, 2004 },
259 { "GL_EXT_texture_snorm", o(EXT_texture_snorm), GL, 2009 },
260 { "GL_EXT_texture_sRGB", o(EXT_texture_sRGB), GL, 2004 },
261 { "GL_EXT_texture_sRGB_decode", o(EXT_texture_sRGB_decode), GL, 2006 },
262 { "GL_EXT_texture_swizzle", o(EXT_texture_swizzle), GL, 2008 },
263 { "GL_EXT_texture_type_2_10_10_10_REV", o(dummy_true), ES2, 2008 },
264 { "GL_EXT_timer_query", o(EXT_timer_query), GL, 2006 },
265 { "GL_EXT_transform_feedback", o(EXT_transform_feedback), GL, 2011 },
266 { "GL_EXT_unpack_subimage", o(dummy_true), ES2, 2011 },
267 { "GL_EXT_vertex_array_bgra", o(EXT_vertex_array_bgra), GL, 2008 },
268 { "GL_EXT_vertex_array", o(dummy_true), GLL, 1995 },
269 { "GL_EXT_color_buffer_float", o(dummy_true), ES3, 2013 },
270
271 /* OES extensions */
272 { "GL_OES_blend_equation_separate", o(EXT_blend_equation_separate), ES1, 2009 },
273 { "GL_OES_blend_func_separate", o(EXT_blend_func_separate), ES1, 2009 },
274 { "GL_OES_blend_subtract", o(dummy_true), ES1, 2009 },
275 { "GL_OES_byte_coordinates", o(dummy_true), ES1, 2002 },
276 { "GL_OES_compressed_ETC1_RGB8_texture", o(OES_compressed_ETC1_RGB8_texture), ES1 | ES2, 2005 },
277 { "GL_OES_compressed_paletted_texture", o(dummy_true), ES1, 2003 },
278 { "GL_OES_depth24", o(dummy_true), ES1 | ES2, 2005 },
279 { "GL_OES_depth32", o(dummy_false), DISABLE, 2005 },
280 { "GL_OES_depth_texture", o(ARB_depth_texture), ES2, 2006 },
281 { "GL_OES_depth_texture_cube_map", o(OES_depth_texture_cube_map), ES2, 2012 },
282 { "GL_OES_draw_texture", o(OES_draw_texture), ES1, 2004 },
283 /* FIXME: Mesa expects GL_OES_EGL_image to be available in OpenGL contexts. */
284 { "GL_OES_EGL_image", o(OES_EGL_image), GL | ES1 | ES2, 2006 },
285 { "GL_OES_EGL_image_external", o(OES_EGL_image_external), ES1 | ES2, 2010 },
286 { "GL_OES_element_index_uint", o(dummy_true), ES1 | ES2, 2005 },
287 { "GL_OES_fbo_render_mipmap", o(dummy_true), ES1 | ES2, 2005 },
288 { "GL_OES_fixed_point", o(dummy_true), ES1, 2002 },
289 { "GL_OES_framebuffer_object", o(dummy_true), ES1, 2005 },
290 { "GL_OES_get_program_binary", o(dummy_true), ES2, 2008 },
291 { "GL_OES_mapbuffer", o(dummy_true), ES1 | ES2, 2005 },
292 { "GL_OES_packed_depth_stencil", o(dummy_true), ES1 | ES2, 2007 },
293 { "GL_OES_point_size_array", o(dummy_true), ES1, 2004 },
294 { "GL_OES_point_sprite", o(ARB_point_sprite), ES1, 2004 },
295 { "GL_OES_query_matrix", o(dummy_true), ES1, 2003 },
296 { "GL_OES_read_format", o(dummy_true), GL | ES1, 2003 },
297 { "GL_OES_rgb8_rgba8", o(dummy_true), ES1 | ES2, 2005 },
298 { "GL_OES_single_precision", o(dummy_true), ES1, 2003 },
299 { "GL_OES_standard_derivatives", o(OES_standard_derivatives), ES2, 2005 },
300 { "GL_OES_stencil1", o(dummy_false), DISABLE, 2005 },
301 { "GL_OES_stencil4", o(dummy_false), DISABLE, 2005 },
302 { "GL_OES_stencil8", o(dummy_true), ES1 | ES2, 2005 },
303 { "GL_OES_stencil_wrap", o(dummy_true), ES1, 2002 },
304 { "GL_OES_surfaceless_context", o(dummy_true), ES1 | ES2, 2012 },
305 { "GL_OES_texture_3D", o(EXT_texture3D), ES2, 2005 },
306 { "GL_OES_texture_cube_map", o(ARB_texture_cube_map), ES1, 2007 },
307 { "GL_OES_texture_env_crossbar", o(ARB_texture_env_crossbar), ES1, 2005 },
308 { "GL_OES_texture_mirrored_repeat", o(dummy_true), ES1, 2005 },
309 { "GL_OES_texture_npot", o(ARB_texture_non_power_of_two), ES1 | ES2, 2005 },
310 { "GL_OES_vertex_array_object", o(dummy_true), ES1 | ES2, 2010 },
311
312 /* KHR extensions */
313 { "GL_KHR_debug", o(dummy_true), GL, 2012 },
314
315 /* Vendor extensions */
316 { "GL_3DFX_texture_compression_FXT1", o(TDFX_texture_compression_FXT1), GL, 1999 },
317 { "GL_AMD_conservative_depth", o(ARB_conservative_depth), GL, 2009 },
318 { "GL_AMD_draw_buffers_blend", o(ARB_draw_buffers_blend), GL, 2009 },
319 { "GL_AMD_performance_monitor", o(AMD_performance_monitor), GL, 2007 },
320 { "GL_AMD_seamless_cubemap_per_texture", o(AMD_seamless_cubemap_per_texture), GL, 2009 },
321 { "GL_AMD_shader_stencil_export", o(ARB_shader_stencil_export), GL, 2009 },
322 { "GL_AMD_shader_trinary_minmax", o(dummy_true), GL, 2012 },
323 { "GL_AMD_vertex_shader_layer", o(AMD_vertex_shader_layer), GLC, 2012 },
324 { "GL_APPLE_object_purgeable", o(APPLE_object_purgeable), GL, 2006 },
325 { "GL_APPLE_packed_pixels", o(dummy_true), GLL, 2002 },
326 { "GL_APPLE_texture_max_level", o(dummy_true), ES1 | ES2, 2009 },
327 { "GL_APPLE_vertex_array_object", o(dummy_true), GLL, 2002 },
328 { "GL_ATI_blend_equation_separate", o(EXT_blend_equation_separate), GL, 2003 },
329 { "GL_ATI_draw_buffers", o(dummy_true), GLL, 2002 },
330 { "GL_ATI_envmap_bumpmap", o(ATI_envmap_bumpmap), GLL, 2001 },
331 { "GL_ATI_fragment_shader", o(ATI_fragment_shader), GLL, 2001 },
332 { "GL_ATI_separate_stencil", o(ATI_separate_stencil), GLL, 2006 },
333 { "GL_ATI_texture_compression_3dc", o(ATI_texture_compression_3dc), GL, 2004 },
334 { "GL_ATI_texture_env_combine3", o(ATI_texture_env_combine3), GLL, 2002 },
335 { "GL_ATI_texture_float", o(ARB_texture_float), GL, 2002 },
336 { "GL_ATI_texture_mirror_once", o(ATI_texture_mirror_once), GL, 2006 },
337 { "GL_IBM_multimode_draw_arrays", o(dummy_true), GL, 1998 },
338 { "GL_IBM_rasterpos_clip", o(dummy_true), GLL, 1996 },
339 { "GL_IBM_texture_mirrored_repeat", o(dummy_true), GLL, 1998 },
340 { "GL_INGR_blend_func_separate", o(EXT_blend_func_separate), GLL, 1999 },
341 { "GL_INTEL_performance_query", o(INTEL_performance_query), GL | ES2, 2013 },
342 { "GL_MESA_pack_invert", o(MESA_pack_invert), GL, 2002 },
343 { "GL_MESA_texture_signed_rgba", o(EXT_texture_snorm), GL, 2009 },
344 { "GL_MESA_window_pos", o(dummy_true), GLL, 2000 },
345 { "GL_MESA_ycbcr_texture", o(MESA_ycbcr_texture), GL, 2002 },
346 { "GL_NV_blend_square", o(dummy_true), GLL, 1999 },
347 { "GL_NV_conditional_render", o(NV_conditional_render), GL, 2008 },
348 { "GL_NV_depth_clamp", o(ARB_depth_clamp), GL, 2001 },
349 { "GL_NV_draw_buffers", o(dummy_true), ES2, 2011 },
350 { "GL_NV_fbo_color_attachments", o(dummy_true), ES2, 2010 },
351 { "GL_NV_fog_distance", o(NV_fog_distance), GLL, 2001 },
352 { "GL_NV_fragment_program_option", o(NV_fragment_program_option), GLL, 2005 },
353 { "GL_NV_light_max_exponent", o(dummy_true), GLL, 1999 },
354 { "GL_NV_packed_depth_stencil", o(dummy_true), GL, 2000 },
355 { "GL_NV_point_sprite", o(NV_point_sprite), GL, 2001 },
356 { "GL_NV_primitive_restart", o(NV_primitive_restart), GLL, 2002 },
357 { "GL_NV_read_buffer", o(dummy_true), ES2, 2011 },
358 { "GL_NV_texgen_reflection", o(dummy_true), GLL, 1999 },
359 { "GL_NV_texture_barrier", o(NV_texture_barrier), GL, 2009 },
360 { "GL_NV_texture_env_combine4", o(NV_texture_env_combine4), GLL, 1999 },
361 { "GL_NV_texture_rectangle", o(NV_texture_rectangle), GLL, 2000 },
362 { "GL_NV_vdpau_interop", o(NV_vdpau_interop), GL, 2010 },
363 { "GL_S3_s3tc", o(ANGLE_texture_compression_dxt), GL, 1999 },
364 { "GL_SGIS_generate_mipmap", o(dummy_true), GLL, 1997 },
365 { "GL_SGIS_texture_border_clamp", o(ARB_texture_border_clamp), GLL, 1997 },
366 { "GL_SGIS_texture_edge_clamp", o(dummy_true), GLL, 1997 },
367 { "GL_SGIS_texture_lod", o(dummy_true), GLL, 1997 },
368 { "GL_SUN_multi_draw_arrays", o(dummy_true), GLL, 1999 },
369
370 { 0, 0, 0, 0 },
371 };
372
373
374 /**
375 * Given an extension name, lookup up the corresponding member of struct
376 * gl_extensions and return that member's offset (in bytes). If the name is
377 * not found in the \c extension_table, return 0.
378 *
379 * \param name Name of extension.
380 * \return Offset of member in struct gl_extensions.
381 */
382 static size_t
383 name_to_offset(const char* name)
384 {
385 const struct extension *i;
386
387 if (name == 0)
388 return 0;
389
390 for (i = extension_table; i->name != 0; ++i) {
391 if (strcmp(name, i->name) == 0)
392 return i->offset;
393 }
394
395 return 0;
396 }
397
398
399 /**
400 * Enable all extensions suitable for a software-only renderer.
401 * This is a convenience function used by the XMesa, OSMesa, GGI drivers, etc.
402 */
403 void
404 _mesa_enable_sw_extensions(struct gl_context *ctx)
405 {
406 ctx->Extensions.ARB_depth_clamp = GL_TRUE;
407 ctx->Extensions.ARB_depth_texture = GL_TRUE;
408 ctx->Extensions.ARB_draw_elements_base_vertex = GL_TRUE;
409 ctx->Extensions.ARB_draw_instanced = GL_TRUE;
410 ctx->Extensions.ARB_explicit_attrib_location = GL_TRUE;
411 ctx->Extensions.ARB_fragment_coord_conventions = GL_TRUE;
412 ctx->Extensions.ARB_fragment_program = GL_TRUE;
413 ctx->Extensions.ARB_fragment_program_shadow = GL_TRUE;
414 ctx->Extensions.ARB_fragment_shader = GL_TRUE;
415 ctx->Extensions.ARB_framebuffer_object = GL_TRUE;
416 ctx->Extensions.ARB_half_float_vertex = GL_TRUE;
417 ctx->Extensions.ARB_map_buffer_range = GL_TRUE;
418 ctx->Extensions.ARB_occlusion_query = GL_TRUE;
419 ctx->Extensions.ARB_occlusion_query2 = GL_TRUE;
420 ctx->Extensions.ARB_point_sprite = GL_TRUE;
421 ctx->Extensions.ARB_shadow = GL_TRUE;
422 ctx->Extensions.ARB_texture_border_clamp = GL_TRUE;
423 ctx->Extensions.ARB_texture_cube_map = GL_TRUE;
424 ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
425 ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
426 ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
427 #ifdef TEXTURE_FLOAT_ENABLED
428 ctx->Extensions.ARB_texture_float = GL_TRUE;
429 #endif
430 ctx->Extensions.ARB_texture_mirror_clamp_to_edge = GL_TRUE;
431 ctx->Extensions.ARB_texture_non_power_of_two = GL_TRUE;
432 ctx->Extensions.ARB_texture_rg = GL_TRUE;
433 ctx->Extensions.ARB_texture_compression_rgtc = GL_TRUE;
434 ctx->Extensions.ARB_vertex_program = GL_TRUE;
435 ctx->Extensions.ARB_vertex_shader = GL_TRUE;
436 ctx->Extensions.ARB_sync = GL_TRUE;
437 ctx->Extensions.APPLE_object_purgeable = GL_TRUE;
438 ctx->Extensions.ATI_envmap_bumpmap = GL_TRUE;
439 ctx->Extensions.ATI_fragment_shader = GL_TRUE;
440 ctx->Extensions.ATI_texture_compression_3dc = GL_TRUE;
441 ctx->Extensions.ATI_texture_env_combine3 = GL_TRUE;
442 ctx->Extensions.ATI_texture_mirror_once = GL_TRUE;
443 ctx->Extensions.ATI_separate_stencil = GL_TRUE;
444 ctx->Extensions.EXT_blend_color = GL_TRUE;
445 ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
446 ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
447 ctx->Extensions.EXT_blend_minmax = GL_TRUE;
448 ctx->Extensions.EXT_depth_bounds_test = GL_TRUE;
449 ctx->Extensions.EXT_draw_buffers2 = GL_TRUE;
450 ctx->Extensions.EXT_pixel_buffer_object = GL_TRUE;
451 ctx->Extensions.EXT_point_parameters = GL_TRUE;
452 ctx->Extensions.EXT_provoking_vertex = GL_TRUE;
453 ctx->Extensions.EXT_stencil_two_side = GL_TRUE;
454 ctx->Extensions.EXT_texture_array = GL_TRUE;
455 ctx->Extensions.EXT_texture_compression_latc = GL_TRUE;
456 ctx->Extensions.EXT_texture_env_dot3 = GL_TRUE;
457 ctx->Extensions.EXT_texture_filter_anisotropic = GL_TRUE;
458 ctx->Extensions.EXT_texture_mirror_clamp = GL_TRUE;
459 ctx->Extensions.EXT_texture_shared_exponent = GL_TRUE;
460 ctx->Extensions.EXT_texture_sRGB = GL_TRUE;
461 ctx->Extensions.EXT_texture_sRGB_decode = GL_TRUE;
462 ctx->Extensions.EXT_texture_swizzle = GL_TRUE;
463 /*ctx->Extensions.EXT_transform_feedback = GL_TRUE;*/
464 ctx->Extensions.EXT_vertex_array_bgra = GL_TRUE;
465 ctx->Extensions.MESA_pack_invert = GL_TRUE;
466 ctx->Extensions.MESA_ycbcr_texture = GL_TRUE;
467 ctx->Extensions.NV_conditional_render = GL_TRUE;
468 ctx->Extensions.NV_point_sprite = GL_TRUE;
469 ctx->Extensions.NV_texture_env_combine4 = GL_TRUE;
470 ctx->Extensions.NV_texture_rectangle = GL_TRUE;
471 ctx->Extensions.NV_fragment_program_option = GL_TRUE;
472 ctx->Extensions.EXT_gpu_program_parameters = GL_TRUE;
473 ctx->Extensions.OES_standard_derivatives = GL_TRUE;
474 ctx->Extensions.TDFX_texture_compression_FXT1 = GL_TRUE;
475 if (ctx->Mesa_DXTn) {
476 ctx->Extensions.ANGLE_texture_compression_dxt = GL_TRUE;
477 ctx->Extensions.EXT_texture_compression_s3tc = GL_TRUE;
478 }
479 }
480
481 /**
482 * Either enable or disable the named extension.
483 * \return offset of extensions withint `ext' or 0 if extension is not known
484 */
485 static size_t
486 set_extension(struct gl_extensions *ext, const char *name, GLboolean state)
487 {
488 size_t offset;
489
490 offset = name_to_offset(name);
491 if (offset != 0 && (offset != o(dummy_true) || state != GL_FALSE)) {
492 ((GLboolean *) ext)[offset] = state;
493 }
494
495 return offset;
496 }
497
498 /**
499 * Either enable or disable the named extension.
500 * \return GL_TRUE for success, GL_FALSE if invalid extension name
501 */
502 static GLboolean
503 set_ctx_extension(struct gl_context *ctx, const char *name, GLboolean state)
504 {
505 size_t offset;
506
507 if (ctx->Extensions.String) {
508 /* The string was already queried - can't change it now! */
509 _mesa_problem(ctx, "Trying to enable/disable extension after "
510 "glGetString(GL_EXTENSIONS): %s", name);
511 return GL_FALSE;
512 }
513
514 offset = set_extension(&ctx->Extensions, name, state);
515 if (offset == 0) {
516 _mesa_problem(ctx, "Trying to enable/disable unknown extension %s",
517 name);
518 return GL_FALSE;
519 } else if (offset == o(dummy_true) && state == GL_FALSE) {
520 _mesa_problem(ctx, "Trying to disable a permanently enabled extension: "
521 "%s", name);
522 return GL_FALSE;
523 } else {
524 return GL_TRUE;
525 }
526 }
527
528 /**
529 * \brief Apply the \c MESA_EXTENSION_OVERRIDE environment variable.
530 *
531 * \c MESA_EXTENSION_OVERRIDE is a space-separated list of extensions to
532 * enable or disable. The list is processed thus:
533 * - Enable recognized extension names that are prefixed with '+'.
534 * - Disable recognized extension names that are prefixed with '-'.
535 * - Enable recognized extension names that are not prefixed.
536 * - Collect unrecognized extension names in a new string.
537 *
538 * \return Space-separated list of unrecognized extension names (which must
539 * be freed). Does not return \c NULL.
540 */
541 static char *
542 get_extension_override( struct gl_context *ctx )
543 {
544 const char *env_const = _mesa_getenv("MESA_EXTENSION_OVERRIDE");
545 char *env;
546 char *ext;
547 char *extra_exts;
548 int len;
549
550 if (env_const == NULL) {
551 /* Return the empty string rather than NULL. This simplifies the logic
552 * of client functions. */
553 return calloc(4, sizeof(char));
554 }
555
556 /* extra_exts: List of unrecognized extensions. */
557 extra_exts = calloc(ALIGN(strlen(env_const) + 2, 4), sizeof(char));
558
559 /* Copy env_const because strtok() is destructive. */
560 env = strdup(env_const);
561 for (ext = strtok(env, " "); ext != NULL; ext = strtok(NULL, " ")) {
562 int enable;
563 int recognized;
564 switch (ext[0]) {
565 case '+':
566 enable = 1;
567 ++ext;
568 break;
569 case '-':
570 enable = 0;
571 ++ext;
572 break;
573 default:
574 enable = 1;
575 break;
576 }
577 recognized = set_ctx_extension(ctx, ext, enable);
578 if (!recognized && enable) {
579 strcat(extra_exts, ext);
580 strcat(extra_exts, " ");
581 }
582 }
583
584 free(env);
585
586 /* Remove trailing space. */
587 len = strlen(extra_exts);
588 if (len > 0 && extra_exts[len - 1] == ' ')
589 extra_exts[len - 1] = '\0';
590
591 return extra_exts;
592 }
593
594
595 /**
596 * \brief Free extra_extensions and cant_disable_extensions strings
597 *
598 * These strings are allocated early during the first context creation by
599 * _mesa_one_time_init_extension_overrides.
600 */
601 static void
602 free_unknown_extensions_strings(void)
603 {
604 free(extra_extensions);
605 free(cant_disable_extensions);
606 }
607
608
609 /**
610 * \brief Initialize extension override tables.
611 *
612 * This should be called one time early during first context initialization.
613 */
614 void
615 _mesa_one_time_init_extension_overrides(void)
616 {
617 const char *env_const = _mesa_getenv("MESA_EXTENSION_OVERRIDE");
618 char *env;
619 char *ext;
620 int len;
621 size_t offset;
622
623 atexit(free_unknown_extensions_strings);
624
625 memset(&_mesa_extension_override_enables, 0, sizeof(struct gl_extensions));
626 memset(&_mesa_extension_override_disables, 0, sizeof(struct gl_extensions));
627
628 if (env_const == NULL) {
629 return;
630 }
631
632 /* extra_exts: List of unrecognized extensions. */
633 extra_extensions = calloc(ALIGN(strlen(env_const) + 2, 4), sizeof(char));
634 cant_disable_extensions = calloc(ALIGN(strlen(env_const) + 2, 4), sizeof(char));
635
636 /* Copy env_const because strtok() is destructive. */
637 env = strdup(env_const);
638 for (ext = strtok(env, " "); ext != NULL; ext = strtok(NULL, " ")) {
639 int enable;
640 bool recognized;
641 switch (ext[0]) {
642 case '+':
643 enable = 1;
644 ++ext;
645 break;
646 case '-':
647 enable = 0;
648 ++ext;
649 break;
650 default:
651 enable = 1;
652 break;
653 }
654
655 offset = set_extension(&_mesa_extension_override_enables, ext, enable);
656 if (offset != 0 && (offset != o(dummy_true) || enable != GL_FALSE)) {
657 ((GLboolean *) &_mesa_extension_override_disables)[offset] = !enable;
658 recognized = true;
659 } else {
660 recognized = false;
661 }
662
663 if (!recognized) {
664 if (enable) {
665 strcat(extra_extensions, ext);
666 strcat(extra_extensions, " ");
667 } else if (offset == o(dummy_true)) {
668 strcat(cant_disable_extensions, ext);
669 strcat(cant_disable_extensions, " ");
670 }
671 }
672 }
673
674 free(env);
675
676 /* Remove trailing space, and free if unused. */
677 len = strlen(extra_extensions);
678 if (len == 0) {
679 free(extra_extensions);
680 extra_extensions = NULL;
681 } else if (extra_extensions[len - 1] == ' ') {
682 extra_extensions[len - 1] = '\0';
683 }
684 len = strlen(cant_disable_extensions);
685 if (len == 0) {
686 free(cant_disable_extensions);
687 cant_disable_extensions = NULL;
688 } else if (cant_disable_extensions[len - 1] == ' ') {
689 cant_disable_extensions[len - 1] = '\0';
690 }
691 }
692
693
694 /**
695 * \brief Initialize extension tables and enable default extensions.
696 *
697 * This should be called during context initialization.
698 * Note: Sets gl_extensions.dummy_true to true.
699 */
700 void
701 _mesa_init_extensions( struct gl_context *ctx )
702 {
703 GLboolean *base = (GLboolean *) &ctx->Extensions;
704 GLboolean *sentinel = base + o(extension_sentinel);
705 GLboolean *i;
706
707 /* First, turn all extensions off. */
708 for (i = base; i != sentinel; ++i)
709 *i = GL_FALSE;
710
711 /* Then, selectively turn default extensions on. */
712 ctx->Extensions.dummy_true = GL_TRUE;
713 ctx->Extensions.EXT_texture3D = GL_TRUE;
714 }
715
716
717 typedef unsigned short extension_index;
718
719
720 /**
721 * Compare two entries of the extensions table. Sorts first by year,
722 * then by name.
723 *
724 * Arguments are indices into extension_table.
725 */
726 static int
727 extension_compare(const void *p1, const void *p2)
728 {
729 extension_index i1 = * (const extension_index *) p1;
730 extension_index i2 = * (const extension_index *) p2;
731 const struct extension *e1 = &extension_table[i1];
732 const struct extension *e2 = &extension_table[i2];
733 int res;
734
735 res = (int)e1->year - (int)e2->year;
736
737 if (res == 0) {
738 res = strcmp(e1->name, e2->name);
739 }
740
741 return res;
742 }
743
744
745 /**
746 * Construct the GL_EXTENSIONS string. Called the first time that
747 * glGetString(GL_EXTENSIONS) is called.
748 */
749 GLubyte*
750 _mesa_make_extension_string(struct gl_context *ctx)
751 {
752 /* The extension string. */
753 char *exts = 0;
754 /* Length of extension string. */
755 size_t length = 0;
756 /* Number of extensions */
757 unsigned count;
758 /* Indices of the extensions sorted by year */
759 extension_index *extension_indices;
760 /* String of extra extensions. */
761 char *extra_extensions = get_extension_override(ctx);
762 GLboolean *base = (GLboolean *) &ctx->Extensions;
763 const struct extension *i;
764 unsigned j;
765 unsigned maxYear = ~0;
766 unsigned api_set = (1 << ctx->API);
767 if (_mesa_is_gles3(ctx))
768 api_set |= ES3;
769
770 /* Check if the MESA_EXTENSION_MAX_YEAR env var is set */
771 {
772 const char *env = getenv("MESA_EXTENSION_MAX_YEAR");
773 if (env) {
774 maxYear = atoi(env);
775 _mesa_debug(ctx, "Note: limiting GL extensions to %u or earlier\n",
776 maxYear);
777 }
778 }
779
780 /* Compute length of the extension string. */
781 count = 0;
782 for (i = extension_table; i->name != 0; ++i) {
783 if (base[i->offset] &&
784 i->year <= maxYear &&
785 (i->api_set & api_set)) {
786 length += strlen(i->name) + 1; /* +1 for space */
787 ++count;
788 }
789 }
790 if (extra_extensions != NULL)
791 length += 1 + strlen(extra_extensions); /* +1 for space */
792
793 exts = calloc(ALIGN(length + 1, 4), sizeof(char));
794 if (exts == NULL) {
795 free(extra_extensions);
796 return NULL;
797 }
798
799 extension_indices = malloc(count * sizeof(extension_index));
800 if (extension_indices == NULL) {
801 free(exts);
802 free(extra_extensions);
803 return NULL;
804 }
805
806 /* Sort extensions in chronological order because certain old applications
807 * (e.g., Quake3 demo) store the extension list in a static size buffer so
808 * chronologically order ensure that the extensions that such applications
809 * expect will fit into that buffer.
810 */
811 j = 0;
812 for (i = extension_table; i->name != 0; ++i) {
813 if (base[i->offset] &&
814 i->year <= maxYear &&
815 (i->api_set & api_set)) {
816 extension_indices[j++] = i - extension_table;
817 }
818 }
819 assert(j == count);
820 qsort(extension_indices, count,
821 sizeof *extension_indices, extension_compare);
822
823 /* Build the extension string.*/
824 for (j = 0; j < count; ++j) {
825 i = &extension_table[extension_indices[j]];
826 assert(base[i->offset] && (i->api_set & api_set));
827 strcat(exts, i->name);
828 strcat(exts, " ");
829 }
830 free(extension_indices);
831 if (extra_extensions != 0) {
832 strcat(exts, extra_extensions);
833 free(extra_extensions);
834 }
835
836 return (GLubyte *) exts;
837 }
838
839 /**
840 * Return number of enabled extensions.
841 */
842 GLuint
843 _mesa_get_extension_count(struct gl_context *ctx)
844 {
845 GLboolean *base;
846 const struct extension *i;
847 unsigned api_set = (1 << ctx->API);
848 if (_mesa_is_gles3(ctx))
849 api_set |= ES3;
850
851 /* only count once */
852 if (ctx->Extensions.Count != 0)
853 return ctx->Extensions.Count;
854
855 base = (GLboolean *) &ctx->Extensions;
856 for (i = extension_table; i->name != 0; ++i) {
857 if (base[i->offset] && (i->api_set & api_set)) {
858 ctx->Extensions.Count++;
859 }
860 }
861 return ctx->Extensions.Count;
862 }
863
864 /**
865 * Return name of i-th enabled extension
866 */
867 const GLubyte *
868 _mesa_get_enabled_extension(struct gl_context *ctx, GLuint index)
869 {
870 const GLboolean *base;
871 size_t n;
872 const struct extension *i;
873 unsigned api_set = (1 << ctx->API);
874 if (_mesa_is_gles3(ctx))
875 api_set |= ES3;
876
877 base = (GLboolean*) &ctx->Extensions;
878 n = 0;
879 for (i = extension_table; i->name != 0; ++i) {
880 if (base[i->offset] && (i->api_set & api_set)) {
881 if (n == index)
882 return (const GLubyte*) i->name;
883 else
884 ++n;
885 }
886 }
887
888 return NULL;
889 }