src/mesa/state_tracker/st_extensions.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * Copyright (c) 2008 VMware, Inc.
   5  * 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
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sub license, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  22  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  23  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  **************************************************************************/
  28
  29 #include "main/imports.h"
  30 #include "main/context.h"
  31 #include "main/macros.h"
  32
  33 #include "pipe/p_context.h"
  34 #include "pipe/p_defines.h"
  35 #include "pipe/p_screen.h"
  36
  37 #include "st_context.h"
  38 #include "st_extensions.h"
  39
  40
  41 static int _min(int a, int b)
  42 {
  43    return (a < b) ? a : b;
  44 }
  45
  46 static float _maxf(float a, float b)
  47 {
  48    return (a > b) ? a : b;
  49 }
  50
  51 static int _clamp(int a, int min, int max)
  52 {
  53    if (a < min)
  54       return min;
  55    else if (a > max)
  56       return max;
  57    else
  58       return a;
  59 }
  60
  61
  62 /**
  63  * Query driver to get implementation limits.
  64  * Note that we have to limit/clamp against Mesa's internal limits too.
  65  */
  66 void st_init_limits(struct st_context *st)
  67 {
  68    struct pipe_screen *screen = st->pipe->screen;
  69    struct gl_constants *c = &st->ctx->Const;
  70    gl_shader_type sh;
  71
  72    c->MaxTextureLevels
  73       = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_2D_LEVELS),
  74             MAX_TEXTURE_LEVELS);
  75
  76    c->Max3DTextureLevels
  77       = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_3D_LEVELS),
  78             MAX_3D_TEXTURE_LEVELS);
  79
  80    c->MaxCubeTextureLevels
  81       = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS),
  82             MAX_CUBE_TEXTURE_LEVELS);
  83
  84    c->MaxTextureRectSize
  85       = _min(1 << (c->MaxTextureLevels - 1), MAX_TEXTURE_RECT_SIZE);
  86
  87    c->MaxTextureImageUnits
  88       = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_IMAGE_UNITS),
  89             MAX_TEXTURE_IMAGE_UNITS);
  90
  91    c->MaxVertexTextureImageUnits
  92       = _min(screen->get_param(screen, PIPE_CAP_MAX_VERTEX_TEXTURE_UNITS),
  93              MAX_VERTEX_TEXTURE_IMAGE_UNITS);
  94
  95    c->MaxCombinedTextureImageUnits
  96       = _min(screen->get_param(screen, PIPE_CAP_MAX_COMBINED_SAMPLERS),
  97              MAX_COMBINED_TEXTURE_IMAGE_UNITS);
  98
  99    c->MaxTextureCoordUnits
 100       = _min(c->MaxTextureImageUnits, MAX_TEXTURE_COORD_UNITS);
 101
 102    c->MaxTextureUnits = _min(c->MaxTextureImageUnits, c->MaxTextureCoordUnits);
 103
 104    c->MaxDrawBuffers
 105       = _clamp(screen->get_param(screen, PIPE_CAP_MAX_RENDER_TARGETS),
 106               1, MAX_DRAW_BUFFERS);
 107
 108    c->MaxLineWidth
 109       = _maxf(1.0f, screen->get_paramf(screen, PIPE_CAP_MAX_LINE_WIDTH));
 110    c->MaxLineWidthAA
 111       = _maxf(1.0f, screen->get_paramf(screen, PIPE_CAP_MAX_LINE_WIDTH_AA));
 112
 113    c->MaxPointSize
 114       = _maxf(1.0f, screen->get_paramf(screen, PIPE_CAP_MAX_POINT_WIDTH));
 115    c->MaxPointSizeAA
 116       = _maxf(1.0f, screen->get_paramf(screen, PIPE_CAP_MAX_POINT_WIDTH_AA));
 117    /* called after _mesa_create_context/_mesa_init_point, fix default user
 118     * settable max point size up
 119     */
 120    st->ctx->Point.MaxSize = MAX2(c->MaxPointSize, c->MaxPointSizeAA);
 121    /* these are not queryable. Note that GL basically mandates a 1.0 minimum
 122     * for non-aa sizes, but we can go down to 0.0 for aa points.
 123     */
 124    c->MinPointSize = 1.0f;
 125    c->MinPointSizeAA = 0.0f;
 126
 127    c->MaxTextureMaxAnisotropy
 128       = _maxf(2.0f, screen->get_paramf(screen, PIPE_CAP_MAX_TEXTURE_ANISOTROPY));
 129
 130    c->MaxTextureLodBias
 131       = screen->get_paramf(screen, PIPE_CAP_MAX_TEXTURE_LOD_BIAS);
 132
 133    c->MaxDrawBuffers
 134       = CLAMP(screen->get_param(screen, PIPE_CAP_MAX_RENDER_TARGETS),
 135               1, MAX_DRAW_BUFFERS);
 136
 137    /* Quads always follow GL provoking rules. */
 138    c->QuadsFollowProvokingVertexConvention = GL_FALSE;
 139
 140    for (sh = 0; sh < MESA_SHADER_TYPES; ++sh) {
 141       struct gl_shader_compiler_options *options =
 142          &st->ctx->ShaderCompilerOptions[sh];
 143       struct gl_program_constants *pc;
 144
 145       switch (sh) {
 146       case PIPE_SHADER_FRAGMENT:
 147          pc = &c->FragmentProgram;
 148          break;
 149       case PIPE_SHADER_VERTEX:
 150          pc = &c->VertexProgram;
 151          break;
 152       case PIPE_SHADER_GEOMETRY:
 153          pc = &c->GeometryProgram;
 154          break;
 155       default:
 156          assert(0);
 157          continue;
 158       }
 159
 160       pc->MaxNativeInstructions    = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_INSTRUCTIONS);
 161       pc->MaxNativeAluInstructions = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_ALU_INSTRUCTIONS);
 162       pc->MaxNativeTexInstructions = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_TEX_INSTRUCTIONS);
 163       pc->MaxNativeTexIndirections = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_TEX_INDIRECTIONS);
 164       pc->MaxNativeAttribs         = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_INPUTS);
 165       pc->MaxNativeTemps           = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_TEMPS);
 166       pc->MaxNativeAddressRegs     = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_ADDRS);
 167       pc->MaxNativeParameters      = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONSTS);
 168       pc->MaxUniformComponents     = 4 * MIN2(pc->MaxNativeParameters, MAX_UNIFORMS);
 169
 170       options->EmitNoNoise = TRUE;
 171
 172       /* TODO: make these more fine-grained if anyone needs it */
 173       options->EmitNoIfs = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONTROL_FLOW_DEPTH);
 174       options->EmitNoLoops = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONTROL_FLOW_DEPTH);
 175       options->EmitNoFunctions = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_SUBROUTINES);
 176       options->EmitNoMainReturn = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_SUBROUTINES);
 177
 178       options->EmitNoCont = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_TGSI_CONT_SUPPORTED);
 179
 180       options->EmitNoIndirectInput = !screen->get_shader_param(screen, sh,
 181                                         PIPE_SHADER_CAP_INDIRECT_INPUT_ADDR);
 182       options->EmitNoIndirectOutput = !screen->get_shader_param(screen, sh,
 183                                         PIPE_SHADER_CAP_INDIRECT_OUTPUT_ADDR);
 184       options->EmitNoIndirectTemp = !screen->get_shader_param(screen, sh,
 185                                         PIPE_SHADER_CAP_INDIRECT_TEMP_ADDR);
 186       options->EmitNoIndirectUniform = !screen->get_shader_param(screen, sh,
 187                                         PIPE_SHADER_CAP_INDIRECT_CONST_ADDR);
 188
 189       if(options->EmitNoLoops)
 190          options->MaxUnrollIterations = MIN2(screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_INSTRUCTIONS), 65536);
 191    }
 192
 193    /* PIPE_CAP_MAX_FS_INPUTS specifies the number of COLORn + GENERICn inputs
 194     * and is set in MaxNativeAttribs. It's always 2 colors + N generic
 195     * attributes. The GLSL compiler never uses COLORn for varyings, so we
 196     * subtract the 2 colors to get the maximum number of varyings (generic
 197     * attributes) supported by a driver. */
 198    c->MaxVarying = screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT, PIPE_SHADER_CAP_MAX_INPUTS) - 2;
 199    c->MaxVarying = MIN2(c->MaxVarying, MAX_VARYING);
 200
 201    /* XXX we'll need a better query here someday */
 202    if (screen->get_param(screen, PIPE_CAP_GLSL)) {
 203       c->GLSLVersion = 120;
 204    }
 205 }
 206
 207
 208 /**
 209  * Use pipe_screen::get_param() to query PIPE_CAP_ values to determine
 210  * which GL extensions are supported.
 211  * Quite a few extensions are always supported because they are standard
 212  * features or can be built on top of other gallium features.
 213  * Some fine tuning may still be needed.
 214  */
 215 void st_init_extensions(struct st_context *st)
 216 {
 217    struct pipe_screen *screen = st->pipe->screen;
 218    struct gl_context *ctx = st->ctx;
 219
 220    /*
 221     * Extensions that are supported by all Gallium drivers:
 222     */
 223    ctx->Extensions.ARB_copy_buffer = GL_TRUE;
 224    ctx->Extensions.ARB_draw_elements_base_vertex = GL_TRUE;
 225    ctx->Extensions.ARB_fragment_coord_conventions = GL_TRUE;
 226    ctx->Extensions.ARB_fragment_program = GL_TRUE;
 227    ctx->Extensions.ARB_map_buffer_range = GL_TRUE;
 228    ctx->Extensions.ARB_multisample = GL_TRUE;
 229    ctx->Extensions.ARB_texture_border_clamp = GL_TRUE; /* XXX temp */
 230    ctx->Extensions.ARB_texture_compression = GL_TRUE;
 231    ctx->Extensions.ARB_texture_cube_map = GL_TRUE;
 232    ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
 233    ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
 234    ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
 235    ctx->Extensions.ARB_vertex_array_object = GL_TRUE;
 236    ctx->Extensions.ARB_vertex_buffer_object = GL_TRUE;
 237    ctx->Extensions.ARB_vertex_program = GL_TRUE;
 238    ctx->Extensions.ARB_window_pos = GL_TRUE;
 239
 240    ctx->Extensions.EXT_blend_color = GL_TRUE;
 241    ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
 242    ctx->Extensions.EXT_blend_logic_op = GL_TRUE;
 243    ctx->Extensions.EXT_blend_minmax = GL_TRUE;
 244    ctx->Extensions.EXT_blend_subtract = GL_TRUE;
 245    ctx->Extensions.EXT_framebuffer_blit = GL_TRUE;
 246    ctx->Extensions.EXT_framebuffer_object = GL_TRUE;
 247    ctx->Extensions.EXT_framebuffer_multisample = GL_TRUE;
 248    ctx->Extensions.EXT_fog_coord = GL_TRUE;
 249    ctx->Extensions.EXT_gpu_program_parameters = GL_TRUE;
 250    ctx->Extensions.EXT_multi_draw_arrays = GL_TRUE;
 251    ctx->Extensions.EXT_pixel_buffer_object = GL_TRUE;
 252    ctx->Extensions.EXT_point_parameters = GL_TRUE;
 253    ctx->Extensions.EXT_provoking_vertex = GL_TRUE;
 254    ctx->Extensions.EXT_secondary_color = GL_TRUE;
 255    ctx->Extensions.EXT_stencil_wrap = GL_TRUE;
 256    ctx->Extensions.EXT_texture_env_add = GL_TRUE;
 257    ctx->Extensions.EXT_texture_env_combine = GL_TRUE;
 258    ctx->Extensions.EXT_texture_env_dot3 = GL_TRUE;
 259    ctx->Extensions.EXT_texture_lod_bias = GL_TRUE;
 260    ctx->Extensions.EXT_vertex_array_bgra = GL_TRUE;
 261
 262    ctx->Extensions.APPLE_vertex_array_object = GL_TRUE;
 263
 264    ctx->Extensions.ATI_texture_env_combine3 = GL_TRUE;
 265
 266    ctx->Extensions.MESA_pack_invert = GL_TRUE;
 267
 268    ctx->Extensions.NV_blend_square = GL_TRUE;
 269    ctx->Extensions.NV_texgen_reflection = GL_TRUE;
 270    ctx->Extensions.NV_texture_env_combine4 = GL_TRUE;
 271    ctx->Extensions.NV_texture_rectangle = GL_TRUE;
 272 #if 0
 273    /* possibly could support the following two */
 274    ctx->Extensions.NV_vertex_program = GL_TRUE;
 275    ctx->Extensions.NV_vertex_program1_1 = GL_TRUE;
 276 #endif
 277
 278 #if FEATURE_OES_EGL_image
 279    ctx->Extensions.OES_EGL_image = GL_TRUE;
 280 #endif
 281 #if FEATURE_OES_draw_texture
 282    ctx->Extensions.OES_draw_texture = GL_TRUE;
 283 #endif
 284
 285    ctx->Extensions.SGIS_generate_mipmap = GL_TRUE;
 286
 287    /*
 288     * Extensions that depend on the driver/hardware:
 289     */
 290    if (screen->get_param(screen, PIPE_CAP_MAX_RENDER_TARGETS) > 0) {
 291       ctx->Extensions.ARB_draw_buffers = GL_TRUE;
 292    }
 293
 294    if (screen->get_param(screen, PIPE_CAP_TEXTURE_SWIZZLE) > 0) {
 295       ctx->Extensions.EXT_texture_swizzle = GL_TRUE;
 296    }
 297
 298    if (screen->get_param(screen, PIPE_CAP_GLSL)) {
 299       ctx->Extensions.ARB_fragment_shader = GL_TRUE;
 300       ctx->Extensions.ARB_vertex_shader = GL_TRUE;
 301       ctx->Extensions.ARB_shader_objects = GL_TRUE;
 302       ctx->Extensions.ARB_shading_language_100 = GL_TRUE;
 303       ctx->Extensions.ARB_explicit_attrib_location = GL_TRUE;
 304       ctx->Extensions.EXT_separate_shader_objects = GL_TRUE;
 305    }
 306
 307    if (screen->get_param(screen, PIPE_CAP_TEXTURE_MIRROR_REPEAT) > 0) {
 308       ctx->Extensions.ARB_texture_mirrored_repeat = GL_TRUE;
 309    }
 310
 311    if (screen->get_param(screen, PIPE_CAP_BLEND_EQUATION_SEPARATE)) {
 312       ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
 313    }
 314
 315    if (screen->get_param(screen, PIPE_CAP_TEXTURE_MIRROR_CLAMP) > 0) {
 316       ctx->Extensions.EXT_texture_mirror_clamp = GL_TRUE;
 317       ctx->Extensions.ATI_texture_mirror_once = GL_TRUE;
 318    }
 319
 320    if (screen->get_param(screen, PIPE_CAP_NPOT_TEXTURES)) {
 321       ctx->Extensions.ARB_texture_non_power_of_two = GL_TRUE;
 322    }
 323
 324    if (screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_IMAGE_UNITS) > 1) {
 325       ctx->Extensions.ARB_multitexture = GL_TRUE;
 326    }
 327
 328    if (screen->get_param(screen, PIPE_CAP_TWO_SIDED_STENCIL)) {
 329       ctx->Extensions.ATI_separate_stencil = GL_TRUE;
 330       ctx->Extensions.EXT_stencil_two_side = GL_TRUE;
 331    }
 332
 333    if (screen->get_param(screen, PIPE_CAP_ANISOTROPIC_FILTER)) {
 334       ctx->Extensions.EXT_texture_filter_anisotropic = GL_TRUE;
 335    }
 336
 337    if (screen->get_param(screen, PIPE_CAP_POINT_SPRITE)) {
 338       ctx->Extensions.ARB_point_sprite = GL_TRUE;
 339       /* GL_NV_point_sprite is not supported by gallium because we don't
 340        * support the GL_POINT_SPRITE_R_MODE_NV option.
 341        */
 342    }
 343
 344    if (screen->get_param(screen, PIPE_CAP_OCCLUSION_QUERY)) {
 345       ctx->Extensions.ARB_occlusion_query = GL_TRUE;
 346    }
 347    if (screen->get_param(screen, PIPE_CAP_TIMER_QUERY)) {
 348      ctx->Extensions.EXT_timer_query = GL_TRUE;
 349    }
 350
 351    if (screen->get_param(screen, PIPE_CAP_TEXTURE_SHADOW_MAP)) {
 352       ctx->Extensions.ARB_depth_texture = GL_TRUE;
 353       ctx->Extensions.ARB_fragment_program_shadow = GL_TRUE;
 354       ctx->Extensions.ARB_shadow = GL_TRUE;
 355       ctx->Extensions.EXT_shadow_funcs = GL_TRUE;
 356       /*ctx->Extensions.ARB_shadow_ambient = GL_TRUE;*/
 357    }
 358
 359    /* GL_EXT_packed_depth_stencil requires both the ability to render to
 360     * a depth/stencil buffer and texture from depth/stencil source.
 361     */
 362    if (screen->is_format_supported(screen, PIPE_FORMAT_S8_USCALED_Z24_UNORM,
 363                                    PIPE_TEXTURE_2D, 0,
 364                                    PIPE_BIND_DEPTH_STENCIL, 0) &&
 365        screen->is_format_supported(screen, PIPE_FORMAT_S8_USCALED_Z24_UNORM,
 366                                    PIPE_TEXTURE_2D, 0,
 367                                    PIPE_BIND_SAMPLER_VIEW, 0)) {
 368       ctx->Extensions.EXT_packed_depth_stencil = GL_TRUE;
 369    }
 370    else if (screen->is_format_supported(screen, PIPE_FORMAT_Z24_UNORM_S8_USCALED,
 371                                         PIPE_TEXTURE_2D, 0,
 372                                         PIPE_BIND_DEPTH_STENCIL, 0) &&
 373             screen->is_format_supported(screen, PIPE_FORMAT_Z24_UNORM_S8_USCALED,
 374                                         PIPE_TEXTURE_2D, 0,
 375                                         PIPE_BIND_SAMPLER_VIEW, 0)) {
 376       ctx->Extensions.EXT_packed_depth_stencil = GL_TRUE;
 377    }
 378
 379    /* sRGB support */
 380    if (screen->is_format_supported(screen, PIPE_FORMAT_A8B8G8R8_SRGB,
 381                                    PIPE_TEXTURE_2D, 0,
 382                                    PIPE_BIND_SAMPLER_VIEW, 0) ||
 383       screen->is_format_supported(screen, PIPE_FORMAT_B8G8R8A8_SRGB,
 384                                    PIPE_TEXTURE_2D, 0,
 385                                    PIPE_BIND_SAMPLER_VIEW, 0)) {
 386       ctx->Extensions.EXT_texture_sRGB = GL_TRUE;
 387    }
 388
 389    if (screen->is_format_supported(screen, PIPE_FORMAT_R8G8_UNORM,
 390                                    PIPE_TEXTURE_2D, 0,
 391                                    PIPE_BIND_SAMPLER_VIEW, 0)) {
 392       ctx->Extensions.ARB_texture_rg = GL_TRUE;
 393    }
 394
 395    /* s3tc support */
 396    if (screen->is_format_supported(screen, PIPE_FORMAT_DXT5_RGBA,
 397                                    PIPE_TEXTURE_2D, 0,
 398                                    PIPE_BIND_SAMPLER_VIEW, 0) &&
 399        (ctx->Mesa_DXTn ||
 400         screen->is_format_supported(screen, PIPE_FORMAT_DXT5_RGBA,
 401                                     PIPE_TEXTURE_2D, 0,
 402                                     PIPE_BIND_RENDER_TARGET, 0))) {
 403       ctx->Extensions.EXT_texture_compression_s3tc = GL_TRUE;
 404       ctx->Extensions.S3_s3tc = GL_TRUE;
 405    }
 406
 407    /* ycbcr support */
 408    if (screen->is_format_supported(screen, PIPE_FORMAT_UYVY,
 409                                    PIPE_TEXTURE_2D, 0,
 410                                    PIPE_BIND_SAMPLER_VIEW, 0) ||
 411        screen->is_format_supported(screen, PIPE_FORMAT_YUYV,
 412                                    PIPE_TEXTURE_2D, 0,
 413                                    PIPE_BIND_SAMPLER_VIEW, 0)) {
 414       ctx->Extensions.MESA_ycbcr_texture = GL_TRUE;
 415    }
 416
 417    /* GL_ARB_framebuffer_object */
 418    if (ctx->Extensions.EXT_packed_depth_stencil) {
 419       /* we support always support GL_EXT_framebuffer_blit */
 420       ctx->Extensions.ARB_framebuffer_object = GL_TRUE;
 421    }
 422
 423    if (st->pipe->render_condition) {
 424       ctx->Extensions.NV_conditional_render = GL_TRUE;
 425    }
 426
 427    if (screen->get_param(screen, PIPE_CAP_INDEP_BLEND_ENABLE)) {
 428       ctx->Extensions.EXT_draw_buffers2 = GL_TRUE;
 429    }
 430
 431    /* GL_ARB_half_float_vertex */
 432    if (screen->is_format_supported(screen, PIPE_FORMAT_R16G16B16A16_FLOAT,
 433                                    PIPE_BUFFER, 0,
 434                                    PIPE_BIND_VERTEX_BUFFER, 0)) {
 435       ctx->Extensions.ARB_half_float_vertex = GL_TRUE;
 436    }
 437
 438 #if 0 /* not yet */
 439    if (screen->get_param(screen, PIPE_CAP_INDEP_BLEND_FUNC)) {
 440       ctx->Extensions.ARB_draw_buffers_blend = GL_TRUE;
 441    }
 442 #endif
 443
 444    if (screen->get_shader_param(screen, PIPE_SHADER_GEOMETRY, PIPE_SHADER_CAP_MAX_INSTRUCTIONS) > 0) {
 445 #if 0 /* XXX re-enable when GLSL compiler again supports geometry shaders */
 446       ctx->Extensions.ARB_geometry_shader4 = GL_TRUE;
 447 #endif
 448    }
 449
 450    if (screen->get_param(screen, PIPE_CAP_PRIMITIVE_RESTART)) {
 451       ctx->Extensions.NV_primitive_restart = GL_TRUE;
 452    }
 453
 454    if (screen->get_param(screen, PIPE_CAP_DEPTH_CLAMP)) {
 455       ctx->Extensions.ARB_depth_clamp = GL_TRUE;
 456    }
 457
 458    if (screen->get_param(screen, PIPE_CAP_SHADER_STENCIL_EXPORT)) {
 459       ctx->Extensions.ARB_shader_stencil_export = GL_TRUE;
 460    }
 461 }