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f3bf5cb164b794a8a3b042885b6e8d4c91ddafce
[mesa.git] / src / mesa / main / extensions.c
1 /*
2 * Mesa 3-D graphics library
3 * Version: 7.6
4 *
5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
6 * Copyright (C) 2009 VMware, Inc. All Rights Reserved.
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the "Software"),
10 * to deal in the Software without restriction, including without limitation
11 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12 * and/or sell copies of the Software, and to permit persons to whom the
13 * Software is furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included
16 * in all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
22 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27 #include "glheader.h"
28 #include "imports.h"
29 #include "context.h"
30 #include "extensions.h"
31 #include "mtypes.h"
32
33
34 #define F(x) offsetof(struct gl_extensions, x)
35 #define ON GL_TRUE
36 #define OFF GL_FALSE
37
38
39 /*
40 * Note: The GL_MESAX_* extensions are placeholders for future ARB extensions.
41 */
42 static const struct {
43 GLboolean enabled;
44 const char *name;
45 int flag_offset;
46 } default_extensions[] = {
47 { OFF, "GL_ARB_blend_func_extended", F(ARB_blend_func_extended) },
48 { ON, "GL_ARB_copy_buffer", F(ARB_copy_buffer) },
49 { OFF, "GL_ARB_depth_buffer_float", F(ARB_depth_buffer_float) },
50 { OFF, "GL_ARB_depth_clamp", F(ARB_depth_clamp) },
51 { OFF, "GL_ARB_depth_texture", F(ARB_depth_texture) },
52 { ON, "GL_ARB_draw_buffers", F(ARB_draw_buffers) },
53 { OFF, "GL_ARB_draw_elements_base_vertex", F(ARB_draw_elements_base_vertex) },
54 { OFF, "GL_ARB_draw_instanced", F(ARB_draw_instanced) },
55 { OFF, "GL_ARB_explicit_attrib_location", F(ARB_explicit_attrib_location) },
56 { OFF, "GL_ARB_fragment_coord_conventions", F(ARB_fragment_coord_conventions) },
57 { OFF, "GL_ARB_fragment_program", F(ARB_fragment_program) },
58 { OFF, "GL_ARB_fragment_program_shadow", F(ARB_fragment_program_shadow) },
59 { OFF, "GL_ARB_fragment_shader", F(ARB_fragment_shader) },
60 { OFF, "GL_ARB_framebuffer_object", F(ARB_framebuffer_object) },
61 /* TODO: reenable this when the new GLSL compiler actually supports them */
62 /* { OFF, "GL_ARB_geometry_shader4", F(ARB_geometry_shader4) }, */
63 { OFF, "GL_ARB_half_float_pixel", F(ARB_half_float_pixel) },
64 { OFF, "GL_ARB_half_float_vertex", F(ARB_half_float_vertex) },
65 { OFF, "GL_ARB_instanced_arrays", F(ARB_instanced_arrays) },
66 { OFF, "GL_ARB_map_buffer_range", F(ARB_map_buffer_range) },
67 { ON, "GL_ARB_multisample", F(ARB_multisample) },
68 { OFF, "GL_ARB_multitexture", F(ARB_multitexture) },
69 { OFF, "GL_ARB_occlusion_query", F(ARB_occlusion_query) },
70 { OFF, "GL_ARB_occlusion_query2", F(ARB_occlusion_query2) },
71 { OFF, "GL_ARB_pixel_buffer_object", F(EXT_pixel_buffer_object) },
72 { OFF, "GL_ARB_point_parameters", F(EXT_point_parameters) },
73 { OFF, "GL_ARB_point_sprite", F(ARB_point_sprite) },
74 { OFF, "GL_ARB_provoking_vertex", F(EXT_provoking_vertex) },
75 { OFF, "GL_ARB_sampler_objects", F(ARB_sampler_objects) },
76 { OFF, "GL_ARB_seamless_cube_map", F(ARB_seamless_cube_map) },
77 { OFF, "GL_ARB_shader_objects", F(ARB_shader_objects) },
78 { OFF, "GL_ARB_shader_stencil_export", F(ARB_shader_stencil_export) },
79 { OFF, "GL_ARB_shading_language_100", F(ARB_shading_language_100) },
80 { OFF, "GL_ARB_shadow", F(ARB_shadow) },
81 { OFF, "GL_ARB_shadow_ambient", F(ARB_shadow_ambient) },
82 { OFF, "GL_ARB_sync", F(ARB_sync) },
83 { OFF, "GL_ARB_texture_border_clamp", F(ARB_texture_border_clamp) },
84 { OFF, "GL_ARB_texture_buffer_object", F(ARB_texture_buffer_object) },
85 { ON, "GL_ARB_texture_compression", F(ARB_texture_compression) },
86 { OFF, "GL_ARB_texture_compression_rgtc", F(ARB_texture_compression_rgtc) },
87 { OFF, "GL_ARB_texture_cube_map", F(ARB_texture_cube_map) },
88 { OFF, "GL_ARB_texture_env_add", F(EXT_texture_env_add) },
89 { OFF, "GL_ARB_texture_env_combine", F(ARB_texture_env_combine) },
90 { OFF, "GL_ARB_texture_env_crossbar", F(ARB_texture_env_crossbar) },
91 { OFF, "GL_ARB_texture_env_dot3", F(ARB_texture_env_dot3) },
92 { OFF, "GL_MESAX_texture_float", F(ARB_texture_float) },
93 { OFF, "GL_ARB_texture_mirrored_repeat", F(ARB_texture_mirrored_repeat)},
94 { OFF, "GL_ARB_texture_multisample", F(ARB_texture_multisample) },
95 { OFF, "GL_ARB_texture_non_power_of_two", F(ARB_texture_non_power_of_two)},
96 { OFF, "GL_ARB_texture_rectangle", F(NV_texture_rectangle) },
97 { OFF, "GL_ARB_texture_rg", F(ARB_texture_rg) },
98 { OFF, "GL_ARB_texture_rgb10_a2ui", F(ARB_texture_rgb10_a2ui) },
99 { OFF, "GL_ARB_texture_swizzle", F(EXT_texture_swizzle) },
100 { ON, "GL_ARB_transpose_matrix", F(ARB_transpose_matrix) },
101 { OFF, "GL_ARB_transform_feedback2", F(ARB_transform_feedback2) },
102 { OFF, "GL_ARB_uniform_buffer_object", F(ARB_uniform_buffer_object) },
103 { OFF, "GL_ARB_vertex_array_bgra", F(EXT_vertex_array_bgra) },
104 { OFF, "GL_ARB_vertex_array_object", F(ARB_vertex_array_object) },
105 { ON, "GL_ARB_vertex_buffer_object", F(ARB_vertex_buffer_object) },
106 { OFF, "GL_ARB_vertex_program", F(ARB_vertex_program) },
107 { OFF, "GL_ARB_vertex_shader", F(ARB_vertex_shader) },
108 { OFF, "GL_ARB_vertex_type_2_10_10_10_rev", F(ARB_vertex_type_2_10_10_10_rev) },
109 { ON, "GL_ARB_window_pos", F(ARB_window_pos) },
110 { ON, "GL_EXT_abgr", F(EXT_abgr) },
111 { ON, "GL_EXT_bgra", F(EXT_bgra) },
112 { OFF, "GL_EXT_blend_color", F(EXT_blend_color) },
113 { OFF, "GL_EXT_blend_equation_separate", F(EXT_blend_equation_separate) },
114 { OFF, "GL_EXT_blend_func_separate", F(EXT_blend_func_separate) },
115 { OFF, "GL_EXT_blend_logic_op", F(EXT_blend_logic_op) },
116 { OFF, "GL_EXT_blend_minmax", F(EXT_blend_minmax) },
117 { OFF, "GL_EXT_blend_subtract", F(EXT_blend_subtract) },
118 { OFF, "GL_EXT_clip_volume_hint", F(EXT_clip_volume_hint) },
119 { ON, "GL_EXT_compiled_vertex_array", F(EXT_compiled_vertex_array) },
120 { ON, "GL_EXT_copy_texture", F(EXT_copy_texture) },
121 { OFF, "GL_EXT_depth_bounds_test", F(EXT_depth_bounds_test) },
122 { OFF, "GL_EXT_draw_buffers2", F(EXT_draw_buffers2) },
123 { OFF, "GL_EXT_draw_instanced", F(ARB_draw_instanced) },
124 { ON, "GL_EXT_draw_range_elements", F(EXT_draw_range_elements) },
125 { OFF, "GL_EXT_framebuffer_blit", F(EXT_framebuffer_blit) },
126 { OFF, "GL_EXT_framebuffer_multisample", F(EXT_framebuffer_multisample) },
127 { OFF, "GL_EXT_framebuffer_object", F(EXT_framebuffer_object) },
128 { OFF, "GL_EXT_framebuffer_sRGB", F(EXT_framebuffer_sRGB) },
129 { OFF, "GL_EXT_fog_coord", F(EXT_fog_coord) },
130 { OFF, "GL_EXT_gpu_program_parameters", F(EXT_gpu_program_parameters) },
131 { OFF, "GL_EXT_gpu_shader4", F(EXT_gpu_shader4) },
132 { ON, "GL_EXT_multi_draw_arrays", F(EXT_multi_draw_arrays) },
133 { OFF, "GL_EXT_packed_depth_stencil", F(EXT_packed_depth_stencil) },
134 { OFF, "GL_EXT_packed_float", F(EXT_packed_float) },
135 { ON, "GL_EXT_packed_pixels", F(EXT_packed_pixels) },
136 { OFF, "GL_EXT_paletted_texture", F(EXT_paletted_texture) },
137 { OFF, "GL_EXT_pixel_buffer_object", F(EXT_pixel_buffer_object) },
138 { OFF, "GL_EXT_point_parameters", F(EXT_point_parameters) },
139 { ON, "GL_EXT_polygon_offset", F(EXT_polygon_offset) },
140 { OFF, "GL_EXT_provoking_vertex", F(EXT_provoking_vertex) },
141 { ON, "GL_EXT_rescale_normal", F(EXT_rescale_normal) },
142 { OFF, "GL_EXT_secondary_color", F(EXT_secondary_color) },
143 { OFF, "GL_EXT_separate_shader_objects", F(EXT_separate_shader_objects) },
144 { ON, "GL_EXT_separate_specular_color", F(EXT_separate_specular_color) },
145 { OFF, "GL_EXT_shadow_funcs", F(EXT_shadow_funcs) },
146 { OFF, "GL_EXT_shared_texture_palette", F(EXT_shared_texture_palette) },
147 { OFF, "GL_EXT_stencil_two_side", F(EXT_stencil_two_side) },
148 { OFF, "GL_EXT_stencil_wrap", F(EXT_stencil_wrap) },
149 { ON, "GL_EXT_subtexture", F(EXT_subtexture) },
150 { ON, "GL_EXT_texture", F(EXT_texture) },
151 { ON, "GL_EXT_texture3D", F(EXT_texture3D) },
152 { OFF, "GL_EXT_texture_array", F(EXT_texture_array) },
153 { OFF, "GL_EXT_texture_compression_s3tc", F(EXT_texture_compression_s3tc) },
154 { OFF, "GL_EXT_texture_compression_rgtc", F(ARB_texture_compression_rgtc) },
155 { OFF, "GL_EXT_texture_cube_map", F(ARB_texture_cube_map) },
156 { ON, "GL_EXT_texture_edge_clamp", F(SGIS_texture_edge_clamp) },
157 { OFF, "GL_EXT_texture_env_add", F(EXT_texture_env_add) },
158 { OFF, "GL_EXT_texture_env_combine", F(EXT_texture_env_combine) },
159 { OFF, "GL_EXT_texture_env_dot3", F(EXT_texture_env_dot3) },
160 { OFF, "GL_EXT_texture_filter_anisotropic", F(EXT_texture_filter_anisotropic) },
161 { OFF, "GL_EXT_texture_integer", F(EXT_texture_integer) },
162 { OFF, "GL_EXT_texture_lod_bias", F(EXT_texture_lod_bias) },
163 { OFF, "GL_EXT_texture_mirror_clamp", F(EXT_texture_mirror_clamp) },
164 { ON, "GL_EXT_texture_object", F(EXT_texture_object) },
165 { OFF, "GL_EXT_texture_rectangle", F(NV_texture_rectangle) },
166 { OFF, "GL_EXT_texture_shared_exponent", F(EXT_texture_shared_exponent) },
167 { OFF, "GL_EXT_texture_sRGB", F(EXT_texture_sRGB) },
168 { OFF, "GL_EXT_texture_swizzle", F(EXT_texture_swizzle) },
169 { OFF, "GL_EXT_timer_query", F(EXT_timer_query) },
170 { OFF, "GL_EXT_transform_feedback", F(EXT_transform_feedback) },
171 { ON, "GL_EXT_vertex_array", F(EXT_vertex_array) },
172 { OFF, "GL_EXT_vertex_array_bgra", F(EXT_vertex_array_bgra) },
173 { OFF, "GL_EXT_vertex_array_set", F(EXT_vertex_array_set) },
174 { OFF, "GL_3DFX_texture_compression_FXT1", F(TDFX_texture_compression_FXT1) },
175 { OFF, "GL_APPLE_client_storage", F(APPLE_client_storage) },
176 { ON, "GL_APPLE_packed_pixels", F(APPLE_packed_pixels) },
177 { OFF, "GL_APPLE_vertex_array_object", F(APPLE_vertex_array_object) },
178 { OFF, "GL_APPLE_object_purgeable", F(APPLE_object_purgeable) },
179 { OFF, "GL_ATI_blend_equation_separate", F(EXT_blend_equation_separate) },
180 { OFF, "GL_ATI_envmap_bumpmap", F(ATI_envmap_bumpmap) },
181 { OFF, "GL_ATI_texture_env_combine3", F(ATI_texture_env_combine3)},
182 { OFF, "GL_ATI_texture_mirror_once", F(ATI_texture_mirror_once)},
183 { OFF, "GL_ATI_fragment_shader", F(ATI_fragment_shader)},
184 { OFF, "GL_ATI_separate_stencil", F(ATI_separate_stencil)},
185 { ON, "GL_IBM_multimode_draw_arrays", F(IBM_multimode_draw_arrays) },
186 { ON, "GL_IBM_rasterpos_clip", F(IBM_rasterpos_clip) },
187 { OFF, "GL_IBM_texture_mirrored_repeat", F(ARB_texture_mirrored_repeat)},
188 { OFF, "GL_INGR_blend_func_separate", F(EXT_blend_func_separate) },
189 { OFF, "GL_MESA_pack_invert", F(MESA_pack_invert) },
190 { OFF, "GL_MESA_resize_buffers", F(MESA_resize_buffers) },
191 { OFF, "GL_MESA_texture_array", F(MESA_texture_array) },
192 { OFF, "GL_MESA_texture_signed_rgba", F(MESA_texture_signed_rgba) },
193 { OFF, "GL_MESA_ycbcr_texture", F(MESA_ycbcr_texture) },
194 { ON, "GL_MESA_window_pos", F(ARB_window_pos) },
195 { OFF, "GL_NV_blend_square", F(NV_blend_square) },
196 { OFF, "GL_NV_conditional_render", F(NV_conditional_render) },
197 { OFF, "GL_NV_depth_clamp", F(ARB_depth_clamp) },
198 { OFF, "GL_NV_fragment_program", F(NV_fragment_program) },
199 { OFF, "GL_NV_fragment_program_option", F(NV_fragment_program_option) },
200 { ON, "GL_NV_light_max_exponent", F(NV_light_max_exponent) },
201 { OFF, "GL_NV_packed_depth_stencil", F(EXT_packed_depth_stencil) },
202 { OFF, "GL_NV_point_sprite", F(NV_point_sprite) },
203 { OFF, "GL_NV_primitive_restart", F(NV_primitive_restart) },
204 { ON, "GL_NV_texgen_reflection", F(NV_texgen_reflection) },
205 { OFF, "GL_NV_texture_env_combine4", F(NV_texture_env_combine4) },
206 { OFF, "GL_NV_texture_rectangle", F(NV_texture_rectangle) },
207 { OFF, "GL_NV_vertex_program", F(NV_vertex_program) },
208 { OFF, "GL_NV_vertex_program1_1", F(NV_vertex_program1_1) },
209 { ON, "GL_OES_read_format", F(OES_read_format) },
210 { OFF, "GL_SGI_texture_color_table", F(SGI_texture_color_table) },
211 { ON, "GL_SGIS_generate_mipmap", F(SGIS_generate_mipmap) },
212 { OFF, "GL_SGIS_texture_border_clamp", F(ARB_texture_border_clamp) },
213 { ON, "GL_SGIS_texture_edge_clamp", F(SGIS_texture_edge_clamp) },
214 { ON, "GL_SGIS_texture_lod", F(SGIS_texture_lod) },
215 { ON, "GL_SUN_multi_draw_arrays", F(EXT_multi_draw_arrays) },
216 { OFF, "GL_S3_s3tc", F(S3_s3tc) },
217 { OFF, "GL_EXT_texture_format_BGRA8888", F(EXT_texture_format_BGRA8888) },
218 #if FEATURE_OES_EGL_image
219 { OFF, "GL_OES_EGL_image", F(OES_EGL_image) },
220 #endif
221 #if FEATURE_OES_draw_texture
222 { OFF, "GL_OES_draw_texture", F(OES_draw_texture) },
223 #endif /* FEATURE_OES_draw_texture */
224 };
225
226
227
228 /**
229 * Enable all extensions suitable for a software-only renderer.
230 * This is a convenience function used by the XMesa, OSMesa, GGI drivers, etc.
231 */
232 void
233 _mesa_enable_sw_extensions(struct gl_context *ctx)
234 {
235 /*ctx->Extensions.ARB_copy_buffer = GL_TRUE;*/
236 ctx->Extensions.ARB_depth_clamp = GL_TRUE;
237 ctx->Extensions.ARB_depth_texture = GL_TRUE;
238 /*ctx->Extensions.ARB_draw_buffers = GL_TRUE;*/
239 ctx->Extensions.ARB_draw_elements_base_vertex = GL_TRUE;
240 ctx->Extensions.ARB_explicit_attrib_location = GL_TRUE;
241 ctx->Extensions.ARB_fragment_coord_conventions = GL_TRUE;
242 #if FEATURE_ARB_fragment_program
243 ctx->Extensions.ARB_fragment_program = GL_TRUE;
244 ctx->Extensions.ARB_fragment_program_shadow = GL_TRUE;
245 #endif
246 #if FEATURE_ARB_fragment_shader
247 ctx->Extensions.ARB_fragment_shader = GL_TRUE;
248 #endif
249 #if FEATURE_ARB_framebuffer_object
250 ctx->Extensions.ARB_framebuffer_object = GL_TRUE;
251 #endif
252 #if FEATURE_ARB_geometry_shader4 && 0
253 /* XXX re-enable when GLSL compiler again supports geometry shaders */
254 ctx->Extensions.ARB_geometry_shader4 = GL_TRUE;
255 #endif
256 ctx->Extensions.ARB_half_float_pixel = GL_TRUE;
257 ctx->Extensions.ARB_half_float_vertex = GL_TRUE;
258 ctx->Extensions.ARB_map_buffer_range = GL_TRUE;
259 ctx->Extensions.ARB_multitexture = GL_TRUE;
260 #if FEATURE_queryobj
261 ctx->Extensions.ARB_occlusion_query = GL_TRUE;
262 #endif
263 ctx->Extensions.ARB_point_sprite = GL_TRUE;
264 #if FEATURE_ARB_shader_objects
265 ctx->Extensions.ARB_shader_objects = GL_TRUE;
266 ctx->Extensions.EXT_separate_shader_objects = GL_TRUE;
267 #endif
268 #if FEATURE_ARB_shading_language_100
269 ctx->Extensions.ARB_shading_language_100 = GL_TRUE;
270 #endif
271 ctx->Extensions.ARB_shadow = GL_TRUE;
272 ctx->Extensions.ARB_shadow_ambient = GL_TRUE;
273 ctx->Extensions.ARB_texture_border_clamp = GL_TRUE;
274 ctx->Extensions.ARB_texture_cube_map = GL_TRUE;
275 ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
276 ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
277 ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
278 /*ctx->Extensions.ARB_texture_float = GL_TRUE;*/
279 ctx->Extensions.ARB_texture_mirrored_repeat = GL_TRUE;
280 ctx->Extensions.ARB_texture_non_power_of_two = GL_TRUE;
281 ctx->Extensions.ARB_texture_rg = GL_TRUE;
282 ctx->Extensions.ARB_vertex_array_object = GL_TRUE;
283 #if FEATURE_ARB_vertex_program
284 ctx->Extensions.ARB_vertex_program = GL_TRUE;
285 #endif
286 #if FEATURE_ARB_vertex_shader
287 ctx->Extensions.ARB_vertex_shader = GL_TRUE;
288 #endif
289 #if FEATURE_ARB_vertex_buffer_object
290 /*ctx->Extensions.ARB_vertex_buffer_object = GL_TRUE;*/
291 #endif
292 #if FEATURE_ARB_sync
293 ctx->Extensions.ARB_sync = GL_TRUE;
294 #endif
295 ctx->Extensions.APPLE_vertex_array_object = GL_TRUE;
296 #if FEATURE_APPLE_object_purgeable
297 ctx->Extensions.APPLE_object_purgeable = GL_TRUE;
298 #endif
299 ctx->Extensions.ATI_envmap_bumpmap = GL_TRUE;
300 #if FEATURE_ATI_fragment_shader
301 ctx->Extensions.ATI_fragment_shader = GL_TRUE;
302 #endif
303 ctx->Extensions.ATI_texture_env_combine3 = GL_TRUE;
304 ctx->Extensions.ATI_texture_mirror_once = GL_TRUE;
305 ctx->Extensions.ATI_separate_stencil = GL_TRUE;
306 ctx->Extensions.EXT_blend_color = GL_TRUE;
307 ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
308 ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
309 ctx->Extensions.EXT_blend_logic_op = GL_TRUE;
310 ctx->Extensions.EXT_blend_minmax = GL_TRUE;
311 ctx->Extensions.EXT_blend_subtract = GL_TRUE;
312 ctx->Extensions.EXT_depth_bounds_test = GL_TRUE;
313 ctx->Extensions.EXT_draw_buffers2 = GL_TRUE;
314 ctx->Extensions.EXT_fog_coord = GL_TRUE;
315 #if FEATURE_EXT_framebuffer_object
316 ctx->Extensions.EXT_framebuffer_object = GL_TRUE;
317 #endif
318 #if FEATURE_EXT_framebuffer_blit
319 ctx->Extensions.EXT_framebuffer_blit = GL_TRUE;
320 #endif
321 #if FEATURE_ARB_framebuffer_object
322 ctx->Extensions.EXT_framebuffer_multisample = GL_TRUE;
323 #endif
324 /*ctx->Extensions.EXT_multi_draw_arrays = GL_TRUE;*/
325 ctx->Extensions.EXT_packed_depth_stencil = GL_TRUE;
326 ctx->Extensions.EXT_paletted_texture = GL_TRUE;
327 #if FEATURE_EXT_pixel_buffer_object
328 ctx->Extensions.EXT_pixel_buffer_object = GL_TRUE;
329 #endif
330 ctx->Extensions.EXT_point_parameters = GL_TRUE;
331 ctx->Extensions.EXT_provoking_vertex = GL_TRUE;
332 ctx->Extensions.EXT_shadow_funcs = GL_TRUE;
333 ctx->Extensions.EXT_secondary_color = GL_TRUE;
334 ctx->Extensions.EXT_shared_texture_palette = GL_TRUE;
335 ctx->Extensions.EXT_stencil_wrap = GL_TRUE;
336 ctx->Extensions.EXT_stencil_two_side = GL_TRUE;
337 ctx->Extensions.EXT_texture_array = GL_TRUE;
338 ctx->Extensions.EXT_texture_env_add = GL_TRUE;
339 ctx->Extensions.EXT_texture_env_combine = GL_TRUE;
340 ctx->Extensions.EXT_texture_env_dot3 = GL_TRUE;
341 ctx->Extensions.EXT_texture_mirror_clamp = GL_TRUE;
342 ctx->Extensions.EXT_texture_lod_bias = GL_TRUE;
343 #if FEATURE_EXT_texture_sRGB
344 ctx->Extensions.EXT_texture_sRGB = GL_TRUE;
345 #endif
346 ctx->Extensions.EXT_texture_swizzle = GL_TRUE;
347 #if FEATURE_EXT_transform_feedback
348 /*ctx->Extensions.EXT_transform_feedback = GL_TRUE;*/
349 #endif
350 ctx->Extensions.EXT_vertex_array_bgra = GL_TRUE;
351 /*ctx->Extensions.IBM_multimode_draw_arrays = GL_TRUE;*/
352 ctx->Extensions.MESA_pack_invert = GL_TRUE;
353 ctx->Extensions.MESA_resize_buffers = GL_TRUE;
354 ctx->Extensions.MESA_texture_array = GL_TRUE;
355 ctx->Extensions.MESA_ycbcr_texture = GL_TRUE;
356 ctx->Extensions.NV_blend_square = GL_TRUE;
357 ctx->Extensions.NV_conditional_render = GL_TRUE;
358 /*ctx->Extensions.NV_light_max_exponent = GL_TRUE;*/
359 ctx->Extensions.NV_point_sprite = GL_TRUE;
360 ctx->Extensions.NV_texture_env_combine4 = GL_TRUE;
361 ctx->Extensions.NV_texture_rectangle = GL_TRUE;
362 /*ctx->Extensions.NV_texgen_reflection = GL_TRUE;*/
363 #if FEATURE_NV_vertex_program
364 ctx->Extensions.NV_vertex_program = GL_TRUE;
365 ctx->Extensions.NV_vertex_program1_1 = GL_TRUE;
366 #endif
367 #if FEATURE_NV_fragment_program
368 ctx->Extensions.NV_fragment_program = GL_TRUE;
369 #endif
370 #if FEATURE_NV_fragment_program && FEATURE_ARB_fragment_program
371 ctx->Extensions.NV_fragment_program_option = GL_TRUE;
372 #endif
373 ctx->Extensions.SGI_texture_color_table = GL_TRUE;
374 /*ctx->Extensions.SGIS_generate_mipmap = GL_TRUE;*/
375 ctx->Extensions.SGIS_texture_edge_clamp = GL_TRUE;
376 #if FEATURE_ARB_vertex_program || FEATURE_ARB_fragment_program
377 ctx->Extensions.EXT_gpu_program_parameters = GL_TRUE;
378 #endif
379 #if FEATURE_texture_fxt1
380 _mesa_enable_extension(ctx, "GL_3DFX_texture_compression_FXT1");
381 #endif
382 #if FEATURE_texture_s3tc
383 if (ctx->Mesa_DXTn) {
384 _mesa_enable_extension(ctx, "GL_EXT_texture_compression_s3tc");
385 _mesa_enable_extension(ctx, "GL_S3_s3tc");
386 }
387 #endif
388 }
389
390
391 /**
392 * Enable common EXT extensions in the ARB_imaging subset.
393 */
394 void
395 _mesa_enable_imaging_extensions(struct gl_context *ctx)
396 {
397 ctx->Extensions.EXT_blend_color = GL_TRUE;
398 ctx->Extensions.EXT_blend_logic_op = GL_TRUE;
399 ctx->Extensions.EXT_blend_minmax = GL_TRUE;
400 ctx->Extensions.EXT_blend_subtract = GL_TRUE;
401 }
402
403
404
405 /**
406 * Enable all OpenGL 1.3 features and extensions.
407 * A convenience function to be called by drivers.
408 */
409 void
410 _mesa_enable_1_3_extensions(struct gl_context *ctx)
411 {
412 /*ctx->Extensions.ARB_multisample = GL_TRUE;*/
413 ctx->Extensions.ARB_multitexture = GL_TRUE;
414 ctx->Extensions.ARB_texture_border_clamp = GL_TRUE;
415 /*ctx->Extensions.ARB_texture_compression = GL_TRUE;*/
416 ctx->Extensions.ARB_texture_cube_map = GL_TRUE;
417 ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
418 ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
419 ctx->Extensions.EXT_texture_env_add = GL_TRUE;
420 /*ctx->Extensions.ARB_transpose_matrix = GL_TRUE;*/
421 }
422
423
424
425 /**
426 * Enable all OpenGL 1.4 features and extensions.
427 * A convenience function to be called by drivers.
428 */
429 void
430 _mesa_enable_1_4_extensions(struct gl_context *ctx)
431 {
432 ctx->Extensions.ARB_depth_texture = GL_TRUE;
433 ctx->Extensions.ARB_shadow = GL_TRUE;
434 ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
435 ctx->Extensions.ARB_texture_mirrored_repeat = GL_TRUE;
436 ctx->Extensions.ARB_window_pos = GL_TRUE;
437 ctx->Extensions.EXT_blend_color = GL_TRUE;
438 ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
439 ctx->Extensions.EXT_blend_minmax = GL_TRUE;
440 ctx->Extensions.EXT_blend_subtract = GL_TRUE;
441 ctx->Extensions.EXT_fog_coord = GL_TRUE;
442 /*ctx->Extensions.EXT_multi_draw_arrays = GL_TRUE;*/
443 ctx->Extensions.EXT_point_parameters = GL_TRUE;
444 ctx->Extensions.EXT_secondary_color = GL_TRUE;
445 ctx->Extensions.EXT_stencil_wrap = GL_TRUE;
446 ctx->Extensions.EXT_texture_lod_bias = GL_TRUE;
447 /*ctx->Extensions.SGIS_generate_mipmap = GL_TRUE;*/
448 }
449
450
451 /**
452 * Enable all OpenGL 1.5 features and extensions.
453 * A convenience function to be called by drivers.
454 */
455 void
456 _mesa_enable_1_5_extensions(struct gl_context *ctx)
457 {
458 ctx->Extensions.ARB_occlusion_query = GL_TRUE;
459 /*ctx->Extensions.ARB_vertex_buffer_object = GL_TRUE;*/
460 ctx->Extensions.EXT_shadow_funcs = GL_TRUE;
461 }
462
463
464 /**
465 * Enable all OpenGL 2.0 features and extensions.
466 * A convenience function to be called by drivers.
467 */
468 void
469 _mesa_enable_2_0_extensions(struct gl_context *ctx)
470 {
471 /*ctx->Extensions.ARB_draw_buffers = GL_TRUE;*/
472 #if FEATURE_ARB_fragment_shader
473 ctx->Extensions.ARB_fragment_shader = GL_TRUE;
474 #endif
475 ctx->Extensions.ARB_point_sprite = GL_TRUE;
476 ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
477 ctx->Extensions.ARB_texture_non_power_of_two = GL_TRUE;
478 #if FEATURE_ARB_shader_objects
479 ctx->Extensions.ARB_shader_objects = GL_TRUE;
480 #endif
481 #if FEATURE_ARB_shading_language_100
482 ctx->Extensions.ARB_shading_language_100 = GL_TRUE;
483 #endif
484 ctx->Extensions.EXT_stencil_two_side = GL_TRUE;
485 #if FEATURE_ARB_vertex_shader
486 ctx->Extensions.ARB_vertex_shader = GL_TRUE;
487 #endif
488 }
489
490
491 /**
492 * Enable all OpenGL 2.1 features and extensions.
493 * A convenience function to be called by drivers.
494 */
495 void
496 _mesa_enable_2_1_extensions(struct gl_context *ctx)
497 {
498 #if FEATURE_EXT_pixel_buffer_object
499 ctx->Extensions.EXT_pixel_buffer_object = GL_TRUE;
500 #endif
501 #if FEATURE_EXT_texture_sRGB
502 ctx->Extensions.EXT_texture_sRGB = GL_TRUE;
503 #endif
504 }
505
506
507 /**
508 * Either enable or disable the named extension.
509 * \return GL_TRUE for success, GL_FALSE if invalid extension name
510 */
511 static GLboolean
512 set_extension( struct gl_context *ctx, const char *name, GLboolean state )
513 {
514 GLboolean *base = (GLboolean *) &ctx->Extensions;
515 GLuint i;
516
517 if (ctx->Extensions.String) {
518 /* The string was already queried - can't change it now! */
519 _mesa_problem(ctx, "Trying to enable/disable extension after glGetString(GL_EXTENSIONS): %s", name);
520 return GL_FALSE;
521 }
522
523 for (i = 0 ; i < Elements(default_extensions) ; i++) {
524 if (strcmp(default_extensions[i].name, name) == 0) {
525 if (default_extensions[i].flag_offset) {
526 GLboolean *enabled = base + default_extensions[i].flag_offset;
527 *enabled = state;
528 }
529 return GL_TRUE;
530 }
531 }
532 return GL_FALSE;
533 }
534
535
536 /**
537 * Enable the named extension.
538 * Typically called by drivers.
539 */
540 void
541 _mesa_enable_extension( struct gl_context *ctx, const char *name )
542 {
543 if (!set_extension(ctx, name, GL_TRUE))
544 _mesa_problem(ctx, "Trying to enable unknown extension: %s", name);
545 }
546
547
548 /**
549 * Disable the named extension.
550 * XXX is this really needed???
551 */
552 void
553 _mesa_disable_extension( struct gl_context *ctx, const char *name )
554 {
555 if (!set_extension(ctx, name, GL_FALSE))
556 _mesa_problem(ctx, "Trying to disable unknown extension: %s", name);
557 }
558
559
560 /**
561 * Check if the i-th extension is enabled.
562 */
563 static GLboolean
564 extension_enabled(struct gl_context *ctx, GLuint index)
565 {
566 const GLboolean *base = (const GLboolean *) &ctx->Extensions;
567 if (!default_extensions[index].flag_offset ||
568 *(base + default_extensions[index].flag_offset)) {
569 return GL_TRUE;
570 }
571 else {
572 return GL_FALSE;
573 }
574 }
575
576
577 /**
578 * Test if the named extension is enabled in this context.
579 */
580 GLboolean
581 _mesa_extension_is_enabled( struct gl_context *ctx, const char *name )
582 {
583 GLuint i;
584
585 for (i = 0 ; i < Elements(default_extensions) ; i++) {
586 if (strcmp(default_extensions[i].name, name) == 0) {
587 return extension_enabled(ctx, i);
588 }
589 }
590 return GL_FALSE;
591 }
592
593
594 /**
595 * Append string 'b' onto string 'a'. Free 'a' and return new string.
596 */
597 static char *
598 append(const char *a, const char *b)
599 {
600 const GLuint aLen = a ? strlen(a) : 0;
601 const GLuint bLen = b ? strlen(b) : 0;
602 char *s = calloc(1, aLen + bLen + 1);
603 if (s) {
604 if (a)
605 memcpy(s, a, aLen);
606 if (b)
607 memcpy(s + aLen, b, bLen);
608 s[aLen + bLen] = '\0';
609 }
610 if (a)
611 free((void *) a);
612 return s;
613 }
614
615
616 /**
617 * Check the MESA_EXTENSION_OVERRIDE env var.
618 * For extension names that are recognized, turn them on. For extension
619 * names that are recognized and prefixed with '-', turn them off.
620 * Return a string of the unknown/leftover names.
621 */
622 static const char *
623 get_extension_override( struct gl_context *ctx )
624 {
625 const char *envExt = _mesa_getenv("MESA_EXTENSION_OVERRIDE");
626 char *extraExt = NULL;
627 char ext[1000];
628 GLuint extLen = 0;
629 GLuint i;
630 GLboolean disableExt = GL_FALSE;
631
632 if (!envExt)
633 return NULL;
634
635 for (i = 0; ; i++) {
636 if (envExt[i] == '\0' || envExt[i] == ' ') {
637 /* terminate/process 'ext' if extLen > 0 */
638 if (extLen > 0) {
639 assert(extLen < sizeof(ext));
640 /* enable extension named by 'ext' */
641 ext[extLen] = 0;
642 if (!set_extension(ctx, ext, !disableExt)) {
643 /* unknown extension name, append it to extraExt */
644 if (extraExt) {
645 extraExt = append(extraExt, " ");
646 }
647 extraExt = append(extraExt, ext);
648 }
649 extLen = 0;
650 disableExt = GL_FALSE;
651 }
652 if (envExt[i] == '\0')
653 break;
654 }
655 else if (envExt[i] == '-') {
656 disableExt = GL_TRUE;
657 }
658 else {
659 /* accumulate this non-space character */
660 ext[extLen++] = envExt[i];
661 }
662 }
663
664 return extraExt;
665 }
666
667
668 /**
669 * Run through the default_extensions array above and set the
670 * ctx->Extensions.ARB/EXT_* flags accordingly.
671 * To be called during context initialization.
672 */
673 void
674 _mesa_init_extensions( struct gl_context *ctx )
675 {
676 GLboolean *base = (GLboolean *) &ctx->Extensions;
677 GLuint i;
678
679 for (i = 0 ; i < Elements(default_extensions) ; i++) {
680 if (default_extensions[i].enabled &&
681 default_extensions[i].flag_offset) {
682 *(base + default_extensions[i].flag_offset) = GL_TRUE;
683 }
684 }
685 }
686
687
688 /**
689 * Construct the GL_EXTENSIONS string. Called the first time that
690 * glGetString(GL_EXTENSIONS) is called.
691 */
692 static GLubyte *
693 compute_extensions( struct gl_context *ctx )
694 {
695 const char *extraExt = get_extension_override(ctx);
696 GLuint extStrLen = 0;
697 char *s;
698 GLuint i;
699
700 /* first, compute length of the extension string */
701 for (i = 0 ; i < Elements(default_extensions) ; i++) {
702 if (extension_enabled(ctx, i)) {
703 extStrLen += (GLuint) strlen(default_extensions[i].name) + 1;
704 }
705 }
706
707 if (extraExt)
708 extStrLen += strlen(extraExt) + 1; /* +1 for space */
709
710 /* allocate the extension string */
711 s = (char *) malloc(extStrLen);
712 if (!s)
713 return NULL;
714
715 /* second, build the extension string */
716 extStrLen = 0;
717 for (i = 0 ; i < Elements(default_extensions) ; i++) {
718 if (extension_enabled(ctx, i)) {
719 GLuint len = (GLuint) strlen(default_extensions[i].name);
720 memcpy(s + extStrLen, default_extensions[i].name, len);
721 extStrLen += len;
722 s[extStrLen] = ' ';
723 extStrLen++;
724 }
725 }
726 ASSERT(extStrLen > 0);
727
728 s[extStrLen - 1] = 0; /* -1 to overwrite trailing the ' ' */
729
730 if (extraExt) {
731 s = append(s, " ");
732 s = append(s, extraExt);
733 }
734
735 return (GLubyte *) s;
736 }
737
738 static size_t
739 append_extension(GLubyte **str, const char *ext)
740 {
741 GLubyte *s = *str;
742 size_t len = strlen(ext);
743
744 if (s) {
745 memcpy(s, ext, len);
746 s[len++] = ' ';
747 s[len] = '\0';
748
749 *str += len;
750 }
751 else {
752 len++;
753 }
754
755 return len;
756 }
757
758
759 static size_t
760 make_extension_string_es1(const struct gl_context *ctx, GLubyte *str)
761 {
762 size_t len = 0;
763
764 /* Core additions */
765 len += append_extension(&str, "GL_OES_byte_coordinates");
766 len += append_extension(&str, "GL_OES_fixed_point");
767 len += append_extension(&str, "GL_OES_single_precision");
768 len += append_extension(&str, "GL_OES_matrix_get");
769
770 /* 1.1 required extensions */
771 len += append_extension(&str, "GL_OES_read_format");
772 len += append_extension(&str, "GL_OES_compressed_paletted_texture");
773 len += append_extension(&str, "GL_OES_point_size_array");
774 len += append_extension(&str, "GL_OES_point_sprite");
775
776 /* 1.1 deprecated extensions */
777 len += append_extension(&str, "GL_OES_query_matrix");
778
779 #if FEATURE_OES_draw_texture
780 if (ctx->Extensions.OES_draw_texture)
781 len += append_extension(&str, "GL_OES_draw_texture");
782 #endif
783
784 if (ctx->Extensions.EXT_blend_equation_separate)
785 len += append_extension(&str, "GL_OES_blend_equation_separate");
786 if (ctx->Extensions.EXT_blend_func_separate)
787 len += append_extension(&str, "GL_OES_blend_func_separate");
788 if (ctx->Extensions.EXT_blend_subtract)
789 len += append_extension(&str, "GL_OES_blend_subtract");
790
791 if (ctx->Extensions.EXT_stencil_wrap)
792 len += append_extension(&str, "GL_OES_stencil_wrap");
793
794 if (ctx->Extensions.ARB_texture_cube_map)
795 len += append_extension(&str, "GL_OES_texture_cube_map");
796 if (ctx->Extensions.ARB_texture_env_crossbar)
797 len += append_extension(&str, "GL_OES_texture_env_crossbar");
798 if (ctx->Extensions.ARB_texture_mirrored_repeat)
799 len += append_extension(&str, "GL_OES_texture_mirrored_repeat");
800
801 if (ctx->Extensions.ARB_framebuffer_object) {
802 len += append_extension(&str, "GL_OES_framebuffer_object");
803 len += append_extension(&str, "GL_OES_depth24");
804 len += append_extension(&str, "GL_OES_depth32");
805 len += append_extension(&str, "GL_OES_fbo_render_mipmap");
806 len += append_extension(&str, "GL_OES_rgb8_rgba8");
807 len += append_extension(&str, "GL_OES_stencil1");
808 len += append_extension(&str, "GL_OES_stencil4");
809 len += append_extension(&str, "GL_OES_stencil8");
810 }
811
812 if (ctx->Extensions.EXT_vertex_array)
813 len += append_extension(&str, "GL_OES_element_index_uint");
814 if (ctx->Extensions.ARB_vertex_buffer_object)
815 len += append_extension(&str, "GL_OES_mapbuffer");
816 if (ctx->Extensions.EXT_texture_filter_anisotropic)
817 len += append_extension(&str, "GL_EXT_texture_filter_anisotropic");
818
819 /* some applications check this for NPOT support */
820 if (ctx->Extensions.ARB_texture_non_power_of_two)
821 len += append_extension(&str, "GL_ARB_texture_non_power_of_two");
822
823 if (ctx->Extensions.EXT_texture_compression_s3tc)
824 len += append_extension(&str, "GL_EXT_texture_compression_dxt1");
825 if (ctx->Extensions.EXT_texture_lod_bias)
826 len += append_extension(&str, "GL_EXT_texture_lod_bias");
827 if (ctx->Extensions.EXT_blend_minmax)
828 len += append_extension(&str, "GL_EXT_blend_minmax");
829 if (ctx->Extensions.EXT_multi_draw_arrays)
830 len += append_extension(&str, "GL_EXT_multi_draw_arrays");
831
832 #if FEATURE_OES_EGL_image
833 if (ctx->Extensions.OES_EGL_image)
834 len += append_extension(&str, "GL_OES_EGL_image");
835 #endif
836
837 return len;
838 }
839
840
841 static GLubyte *
842 compute_extensions_es1(const struct gl_context *ctx)
843 {
844 GLubyte *s;
845 unsigned int len;
846
847 len = make_extension_string_es1(ctx, NULL);
848 s = malloc(len + 1);
849 if (!s)
850 return NULL;
851 make_extension_string_es1(ctx, s);
852
853 return s;
854 }
855
856 static size_t
857 make_extension_string_es2(const struct gl_context *ctx, GLubyte *str)
858 {
859 size_t len = 0;
860
861 if (ctx->Extensions.ARB_framebuffer_object) {
862 len += append_extension(&str, "GL_OES_depth24");
863 len += append_extension(&str, "GL_OES_depth32");
864 len += append_extension(&str, "GL_OES_fbo_render_mipmap");
865 len += append_extension(&str, "GL_OES_rgb8_rgba8");
866 len += append_extension(&str, "GL_OES_stencil1");
867 len += append_extension(&str, "GL_OES_stencil4");
868 }
869
870 if (ctx->Extensions.EXT_vertex_array)
871 len += append_extension(&str, "GL_OES_element_index_uint");
872 if (ctx->Extensions.ARB_vertex_buffer_object)
873 len += append_extension(&str, "GL_OES_mapbuffer");
874
875 #if 0
876 /* disabled because of missing GLSL support */
877 if (ctx->Extensions.EXT_texture3D)
878 len += append_extension(&str, "GL_OES_texture_3D");
879 #endif
880
881 if (ctx->Extensions.ARB_texture_non_power_of_two)
882 len += append_extension(&str, "GL_OES_texture_npot");
883 if (ctx->Extensions.EXT_texture_filter_anisotropic)
884 len += append_extension(&str, "GL_EXT_texture_filter_anisotropic");
885
886 len += append_extension(&str, "GL_EXT_texture_type_2_10_10_10_REV");
887 if (ctx->Extensions.ARB_depth_texture)
888 len += append_extension(&str, "GL_OES_depth_texture");
889 if (ctx->Extensions.EXT_packed_depth_stencil)
890 len += append_extension(&str, "GL_OES_packed_depth_stencil");
891 if (ctx->Extensions.ARB_fragment_shader)
892 len += append_extension(&str, "GL_OES_standard_derivatives");
893
894 if (ctx->Extensions.EXT_texture_compression_s3tc)
895 len += append_extension(&str, "GL_EXT_texture_compression_dxt1");
896 if (ctx->Extensions.EXT_blend_minmax)
897 len += append_extension(&str, "GL_EXT_blend_minmax");
898 if (ctx->Extensions.EXT_multi_draw_arrays)
899 len += append_extension(&str, "GL_EXT_multi_draw_arrays");
900
901 #if FEATURE_OES_EGL_image
902 if (ctx->Extensions.OES_EGL_image)
903 len += append_extension(&str, "GL_OES_EGL_image");
904 #endif
905
906 if (ctx->Extensions.EXT_texture_format_BGRA8888)
907 len += append_extension(&str, "GL_EXT_texture_format_BGRA8888");
908
909 return len;
910 }
911
912 static GLubyte *
913 compute_extensions_es2(struct gl_context *ctx)
914 {
915 GLubyte *s;
916 unsigned int len;
917
918 len = make_extension_string_es2(ctx, NULL);
919 s = malloc(len + 1);
920 if (!s)
921 return NULL;
922 make_extension_string_es2(ctx, s);
923
924 return s;
925 }
926
927
928 GLubyte *
929 _mesa_make_extension_string(struct gl_context *ctx)
930 {
931 switch (ctx->API) {
932 case API_OPENGL:
933 return compute_extensions(ctx);
934 case API_OPENGLES2:
935 return compute_extensions_es2(ctx);
936 case API_OPENGLES:
937 return compute_extensions_es1(ctx);
938 default:
939 assert(0);
940 return NULL;
941 }
942 }
943
944 /**
945 * Return number of enabled extensions.
946 */
947 GLuint
948 _mesa_get_extension_count(struct gl_context *ctx)
949 {
950 GLuint i;
951
952 /* only count once */
953 if (!ctx->Extensions.Count) {
954 for (i = 0; i < Elements(default_extensions); i++) {
955 if (extension_enabled(ctx, i)) {
956 ctx->Extensions.Count++;
957 }
958 }
959 }
960
961 if (0)
962 _mesa_debug(ctx, "%u of %d extensions enabled\n", ctx->Extensions.Count,
963 (int) Elements(default_extensions));
964
965 return ctx->Extensions.Count;
966 }
967
968
969 /**
970 * Return name of i-th enabled extension
971 */
972 const GLubyte *
973 _mesa_get_enabled_extension(struct gl_context *ctx, GLuint index)
974 {
975 GLuint i;
976
977 for (i = 0; i < Elements(default_extensions); i++) {
978 if (extension_enabled(ctx, i)) {
979 if (index == 0)
980 return (const GLubyte *) default_extensions[i].name;
981 index--;
982 }
983 }
984
985 return NULL;
986 }