src/mesa/state_tracker/st_cb_clear.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  * Copyright 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
   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  /*
  30   * Authors:
  31   *   Keith Whitwell <keith@tungstengraphics.com>
  32   *   Brian Paul
  33   *   Michel Dänzer
  34   */
  35
  36 #include "main/glheader.h"
  37 #include "main/accum.h"
  38 #include "main/formats.h"
  39 #include "main/macros.h"
  40 #include "program/prog_instruction.h"
  41 #include "st_context.h"
  42 #include "st_atom.h"
  43 #include "st_cb_clear.h"
  44 #include "st_cb_fbo.h"
  45 #include "st_format.h"
  46 #include "st_program.h"
  47
  48 #include "pipe/p_context.h"
  49 #include "pipe/p_shader_tokens.h"
  50 #include "pipe/p_state.h"
  51 #include "pipe/p_defines.h"
  52 #include "util/u_format.h"
  53 #include "util/u_inlines.h"
  54 #include "util/u_simple_shaders.h"
  55 #include "util/u_draw_quad.h"
  56
  57 #include "cso_cache/cso_context.h"
  58
  59
  60 /**
  61  * Do per-context initialization for glClear.
  62  */
  63 void
  64 st_init_clear(struct st_context *st)
  65 {
  66    struct pipe_screen *pscreen = st->pipe->screen;
  67
  68    memset(&st->clear, 0, sizeof(st->clear));
  69
  70    st->clear.raster.gl_rasterization_rules = 1;
  71    st->clear.raster.depth_clip = 1;
  72    st->clear.enable_ds_separate = pscreen->get_param(pscreen, PIPE_CAP_DEPTHSTENCIL_CLEAR_SEPARATE);
  73 }
  74
  75
  76 /**
  77  * Free per-context state for glClear.
  78  */
  79 void
  80 st_destroy_clear(struct st_context *st)
  81 {
  82    if (st->clear.fs) {
  83       cso_delete_fragment_shader(st->cso_context, st->clear.fs);
  84       st->clear.fs = NULL;
  85    }
  86    if (st->clear.vs) {
  87       cso_delete_vertex_shader(st->cso_context, st->clear.vs);
  88       st->clear.vs = NULL;
  89    }
  90    if (st->clear.vbuf) {
  91       pipe_resource_reference(&st->clear.vbuf, NULL);
  92       st->clear.vbuf = NULL;
  93    }
  94 }
  95
  96
  97 /**
  98  * Helper function to set the fragment shaders.
  99  */
 100 static INLINE void
 101 set_fragment_shader(struct st_context *st)
 102 {
 103    if (!st->clear.fs)
 104       st->clear.fs = util_make_fragment_passthrough_shader(st->pipe);
 105
 106    cso_set_fragment_shader_handle(st->cso_context, st->clear.fs);
 107 }
 108
 109
 110 /**
 111  * Helper function to set the vertex shader.
 112  */
 113 static INLINE void
 114 set_vertex_shader(struct st_context *st)
 115 {
 116    /* vertex shader - still required to provide the linkage between
 117     * fragment shader input semantics and vertex_element/buffers.
 118     */
 119    if (!st->clear.vs)
 120    {
 121       const uint semantic_names[] = { TGSI_SEMANTIC_POSITION,
 122                                       TGSI_SEMANTIC_COLOR };
 123       const uint semantic_indexes[] = { 0, 0 };
 124       st->clear.vs = util_make_vertex_passthrough_shader(st->pipe, 2,
 125                                                          semantic_names,
 126                                                          semantic_indexes);
 127    }
 128
 129    cso_set_vertex_shader_handle(st->cso_context, st->clear.vs);
 130 }
 131
 132
 133 /**
 134  * Draw a screen-aligned quadrilateral.
 135  * Coords are clip coords with y=0=bottom.
 136  */
 137 static void
 138 draw_quad(struct st_context *st,
 139           float x0, float y0, float x1, float y1, GLfloat z,
 140           const union pipe_color_union *color)
 141 {
 142    struct pipe_context *pipe = st->pipe;
 143
 144    /* XXX: Need to improve buffer_write to allow NO_WAIT (as well as
 145     * no_flush) updates to buffers where we know there is no conflict
 146     * with previous data.  Currently using max_slots > 1 will cause
 147     * synchronous rendering if the driver flushes its command buffers
 148     * between one bitmap and the next.  Our flush hook below isn't
 149     * sufficient to catch this as the driver doesn't tell us when it
 150     * flushes its own command buffers.  Until this gets fixed, pay the
 151     * price of allocating a new buffer for each bitmap cache-flush to
 152     * avoid synchronous rendering.
 153     */
 154    const GLuint max_slots = 1; /* 1024 / sizeof(st->clear.vertices); */
 155    GLuint i;
 156
 157    if (st->clear.vbuf_slot >= max_slots) {
 158       pipe_resource_reference(&st->clear.vbuf, NULL);
 159       st->clear.vbuf_slot = 0;
 160    }
 161
 162    if (!st->clear.vbuf) {
 163       st->clear.vbuf = pipe_buffer_create(pipe->screen,
 164                                           PIPE_BIND_VERTEX_BUFFER,
 165                                           PIPE_USAGE_STREAM,
 166                                           max_slots * sizeof(st->clear.vertices));
 167    }
 168
 169    if (!st->clear.vbuf) {
 170       /* ran out of memory */
 171       return;
 172    }
 173
 174    /* positions */
 175    st->clear.vertices[0][0][0] = x0;
 176    st->clear.vertices[0][0][1] = y0;
 177
 178    st->clear.vertices[1][0][0] = x1;
 179    st->clear.vertices[1][0][1] = y0;
 180
 181    st->clear.vertices[2][0][0] = x1;
 182    st->clear.vertices[2][0][1] = y1;
 183
 184    st->clear.vertices[3][0][0] = x0;
 185    st->clear.vertices[3][0][1] = y1;
 186
 187    /* same for all verts: */
 188    for (i = 0; i < 4; i++) {
 189       st->clear.vertices[i][0][2] = z;
 190       st->clear.vertices[i][0][3] = 1.0;
 191       st->clear.vertices[i][1][0] = color->f[0];
 192       st->clear.vertices[i][1][1] = color->f[1];
 193       st->clear.vertices[i][1][2] = color->f[2];
 194       st->clear.vertices[i][1][3] = color->f[3];
 195    }
 196
 197    /* put vertex data into vbuf */
 198    pipe_buffer_write_nooverlap(st->pipe, st->clear.vbuf,
 199                                            st->clear.vbuf_slot
 200                                              * sizeof(st->clear.vertices),
 201                                            sizeof(st->clear.vertices),
 202                                            st->clear.vertices);
 203
 204    /* draw */
 205    util_draw_vertex_buffer(pipe,
 206                            st->cso_context,
 207                            st->clear.vbuf,
 208                            st->clear.vbuf_slot * sizeof(st->clear.vertices),
 209                            PIPE_PRIM_TRIANGLE_FAN,
 210                            4,  /* verts */
 211                            2); /* attribs/vert */
 212
 213    /* Increment slot */
 214    st->clear.vbuf_slot++;
 215 }
 216
 217
 218
 219 /**
 220  * Do glClear by drawing a quadrilateral.
 221  * The vertices of the quad will be computed from the
 222  * ctx->DrawBuffer->_X/Ymin/max fields.
 223  */
 224 static void
 225 clear_with_quad(struct gl_context *ctx,
 226                 GLboolean color, GLboolean depth, GLboolean stencil)
 227 {
 228    struct st_context *st = st_context(ctx);
 229    const struct gl_framebuffer *fb = ctx->DrawBuffer;
 230    const GLfloat fb_width = (GLfloat) fb->Width;
 231    const GLfloat fb_height = (GLfloat) fb->Height;
 232    const GLfloat x0 = (GLfloat) ctx->DrawBuffer->_Xmin / fb_width * 2.0f - 1.0f;
 233    const GLfloat x1 = (GLfloat) ctx->DrawBuffer->_Xmax / fb_width * 2.0f - 1.0f;
 234    const GLfloat y0 = (GLfloat) ctx->DrawBuffer->_Ymin / fb_height * 2.0f - 1.0f;
 235    const GLfloat y1 = (GLfloat) ctx->DrawBuffer->_Ymax / fb_height * 2.0f - 1.0f;
 236    union pipe_color_union clearColor;
 237
 238    /*
 239    printf("%s %s%s%s %f,%f %f,%f\n", __FUNCTION__,
 240           color ? "color, " : "",
 241           depth ? "depth, " : "",
 242           stencil ? "stencil" : "",
 243           x0, y0,
 244           x1, y1);
 245    */
 246
 247    cso_save_blend(st->cso_context);
 248    cso_save_stencil_ref(st->cso_context);
 249    cso_save_depth_stencil_alpha(st->cso_context);
 250    cso_save_rasterizer(st->cso_context);
 251    cso_save_viewport(st->cso_context);
 252    cso_save_fragment_shader(st->cso_context);
 253    cso_save_stream_outputs(st->cso_context);
 254    cso_save_vertex_shader(st->cso_context);
 255    cso_save_geometry_shader(st->cso_context);
 256    cso_save_vertex_elements(st->cso_context);
 257    cso_save_vertex_buffers(st->cso_context);
 258
 259    /* blend state: RGBA masking */
 260    {
 261       struct pipe_blend_state blend;
 262       memset(&blend, 0, sizeof(blend));
 263       blend.rt[0].rgb_src_factor = PIPE_BLENDFACTOR_ONE;
 264       blend.rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
 265       blend.rt[0].rgb_dst_factor = PIPE_BLENDFACTOR_ZERO;
 266       blend.rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ZERO;
 267       if (color) {
 268          if (ctx->Color.ColorMask[0][0])
 269             blend.rt[0].colormask |= PIPE_MASK_R;
 270          if (ctx->Color.ColorMask[0][1])
 271             blend.rt[0].colormask |= PIPE_MASK_G;
 272          if (ctx->Color.ColorMask[0][2])
 273             blend.rt[0].colormask |= PIPE_MASK_B;
 274          if (ctx->Color.ColorMask[0][3])
 275             blend.rt[0].colormask |= PIPE_MASK_A;
 276          if (st->ctx->Color.DitherFlag)
 277             blend.dither = 1;
 278       }
 279       cso_set_blend(st->cso_context, &blend);
 280    }
 281
 282    /* depth_stencil state: always pass/set to ref value */
 283    {
 284       struct pipe_depth_stencil_alpha_state depth_stencil;
 285       memset(&depth_stencil, 0, sizeof(depth_stencil));
 286       if (depth) {
 287          depth_stencil.depth.enabled = 1;
 288          depth_stencil.depth.writemask = 1;
 289          depth_stencil.depth.func = PIPE_FUNC_ALWAYS;
 290       }
 291
 292       if (stencil) {
 293          struct pipe_stencil_ref stencil_ref;
 294          memset(&stencil_ref, 0, sizeof(stencil_ref));
 295          depth_stencil.stencil[0].enabled = 1;
 296          depth_stencil.stencil[0].func = PIPE_FUNC_ALWAYS;
 297          depth_stencil.stencil[0].fail_op = PIPE_STENCIL_OP_REPLACE;
 298          depth_stencil.stencil[0].zpass_op = PIPE_STENCIL_OP_REPLACE;
 299          depth_stencil.stencil[0].zfail_op = PIPE_STENCIL_OP_REPLACE;
 300          depth_stencil.stencil[0].valuemask = 0xff;
 301          depth_stencil.stencil[0].writemask = ctx->Stencil.WriteMask[0] & 0xff;
 302          stencil_ref.ref_value[0] = ctx->Stencil.Clear;
 303          cso_set_stencil_ref(st->cso_context, &stencil_ref);
 304       }
 305
 306       cso_set_depth_stencil_alpha(st->cso_context, &depth_stencil);
 307    }
 308
 309    cso_set_vertex_elements(st->cso_context, 2, st->velems_util_draw);
 310    cso_set_stream_outputs(st->cso_context, 0, NULL, 0);
 311
 312    cso_set_rasterizer(st->cso_context, &st->clear.raster);
 313
 314    /* viewport state: viewport matching window dims */
 315    {
 316       const GLboolean invert = (st_fb_orientation(fb) == Y_0_TOP);
 317       struct pipe_viewport_state vp;
 318       vp.scale[0] = 0.5f * fb_width;
 319       vp.scale[1] = fb_height * (invert ? -0.5f : 0.5f);
 320       vp.scale[2] = 1.0f;
 321       vp.scale[3] = 1.0f;
 322       vp.translate[0] = 0.5f * fb_width;
 323       vp.translate[1] = 0.5f * fb_height;
 324       vp.translate[2] = 0.0f;
 325       vp.translate[3] = 0.0f;
 326       cso_set_viewport(st->cso_context, &vp);
 327    }
 328
 329    set_fragment_shader(st);
 330    set_vertex_shader(st);
 331    cso_set_geometry_shader_handle(st->cso_context, NULL);
 332
 333    if (ctx->DrawBuffer->_ColorDrawBuffers[0]) {
 334       st_translate_color(ctx->Color.ClearColor.f,
 335                                ctx->DrawBuffer->_ColorDrawBuffers[0]->_BaseFormat,
 336                                clearColor.f);
 337    }
 338
 339    /* draw quad matching scissor rect */
 340    draw_quad(st, x0, y0, x1, y1, (GLfloat) ctx->Depth.Clear, &clearColor);
 341
 342    /* Restore pipe state */
 343    cso_restore_blend(st->cso_context);
 344    cso_restore_stencil_ref(st->cso_context);
 345    cso_restore_depth_stencil_alpha(st->cso_context);
 346    cso_restore_rasterizer(st->cso_context);
 347    cso_restore_viewport(st->cso_context);
 348    cso_restore_fragment_shader(st->cso_context);
 349    cso_restore_vertex_shader(st->cso_context);
 350    cso_restore_geometry_shader(st->cso_context);
 351    cso_restore_vertex_elements(st->cso_context);
 352    cso_restore_vertex_buffers(st->cso_context);
 353    cso_restore_stream_outputs(st->cso_context);
 354 }
 355
 356
 357 /**
 358  * Determine if we need to clear the depth buffer by drawing a quad.
 359  */
 360 static INLINE GLboolean
 361 check_clear_color_with_quad(struct gl_context *ctx, struct gl_renderbuffer *rb)
 362 {
 363    if (ctx->Scissor.Enabled &&
 364        (ctx->Scissor.X != 0 ||
 365         ctx->Scissor.Y != 0 ||
 366         ctx->Scissor.Width < rb->Width ||
 367         ctx->Scissor.Height < rb->Height))
 368       return GL_TRUE;
 369
 370    if (!ctx->Color.ColorMask[0][0] ||
 371        !ctx->Color.ColorMask[0][1] ||
 372        !ctx->Color.ColorMask[0][2] ||
 373        !ctx->Color.ColorMask[0][3])
 374       return GL_TRUE;
 375
 376    return GL_FALSE;
 377 }
 378
 379
 380 /**
 381  * Determine if we need to clear the combiend depth/stencil buffer by
 382  * drawing a quad.
 383  */
 384 static INLINE GLboolean
 385 check_clear_depth_stencil_with_quad(struct gl_context *ctx, struct gl_renderbuffer *rb)
 386 {
 387    const GLuint stencilMax = 0xff;
 388    GLboolean maskStencil
 389       = (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
 390
 391    assert(_mesa_get_format_bits(rb->Format, GL_STENCIL_BITS) > 0);
 392
 393    if (ctx->Scissor.Enabled &&
 394        (ctx->Scissor.X != 0 ||
 395         ctx->Scissor.Y != 0 ||
 396         ctx->Scissor.Width < rb->Width ||
 397         ctx->Scissor.Height < rb->Height))
 398       return GL_TRUE;
 399
 400    if (maskStencil)
 401       return GL_TRUE;
 402
 403    return GL_FALSE;
 404 }
 405
 406
 407 /**
 408  * Determine if we need to clear the depth buffer by drawing a quad.
 409  */
 410 static INLINE GLboolean
 411 check_clear_depth_with_quad(struct gl_context *ctx, struct gl_renderbuffer *rb,
 412                             boolean ds_separate)
 413 {
 414    const struct st_renderbuffer *strb = st_renderbuffer(rb);
 415    const GLboolean isDS = util_format_is_depth_and_stencil(strb->surface->format);
 416
 417    if (ctx->Scissor.Enabled &&
 418        (ctx->Scissor.X != 0 ||
 419         ctx->Scissor.Y != 0 ||
 420         ctx->Scissor.Width < rb->Width ||
 421         ctx->Scissor.Height < rb->Height))
 422       return GL_TRUE;
 423
 424    if (!ds_separate && isDS && ctx->DrawBuffer->Visual.stencilBits > 0)
 425       return GL_TRUE;
 426
 427    return GL_FALSE;
 428 }
 429
 430
 431 /**
 432  * Determine if we need to clear the stencil buffer by drawing a quad.
 433  */
 434 static INLINE GLboolean
 435 check_clear_stencil_with_quad(struct gl_context *ctx, struct gl_renderbuffer *rb,
 436                               boolean ds_separate)
 437 {
 438    const struct st_renderbuffer *strb = st_renderbuffer(rb);
 439    const GLboolean isDS = util_format_is_depth_and_stencil(strb->surface->format);
 440    const GLuint stencilMax = 0xff;
 441    const GLboolean maskStencil
 442       = (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
 443
 444    assert(_mesa_get_format_bits(rb->Format, GL_STENCIL_BITS) > 0);
 445
 446    if (maskStencil)
 447       return GL_TRUE;
 448
 449    if (ctx->Scissor.Enabled &&
 450        (ctx->Scissor.X != 0 ||
 451         ctx->Scissor.Y != 0 ||
 452         ctx->Scissor.Width < rb->Width ||
 453         ctx->Scissor.Height < rb->Height))
 454       return GL_TRUE;
 455
 456    /* This is correct, but it is necessary to look at the depth clear
 457     * value held in the surface when it comes time to issue the clear,
 458     * rather than taking depth and stencil clear values from the
 459     * current state.
 460     */
 461    if (!ds_separate && isDS && ctx->DrawBuffer->Visual.depthBits > 0)
 462       return GL_TRUE;
 463
 464    return GL_FALSE;
 465 }
 466
 467
 468
 469 /**
 470  * Called when we need to flush.
 471  */
 472 void
 473 st_flush_clear(struct st_context *st)
 474 {
 475    /* Release vertex buffer to avoid synchronous rendering if we were
 476     * to map it in the next frame.
 477     */
 478    pipe_resource_reference(&st->clear.vbuf, NULL);
 479    st->clear.vbuf_slot = 0;
 480 }
 481
 482
 483
 484 /**
 485  * Called via ctx->Driver.Clear()
 486  */
 487 static void
 488 st_Clear(struct gl_context *ctx, GLbitfield mask)
 489 {
 490    static const GLbitfield BUFFER_BITS_DS
 491       = (BUFFER_BIT_DEPTH | BUFFER_BIT_STENCIL);
 492    struct st_context *st = st_context(ctx);
 493    struct gl_renderbuffer *depthRb
 494       = ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
 495    struct gl_renderbuffer *stencilRb
 496       = ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
 497    GLbitfield quad_buffers = 0x0;
 498    GLbitfield clear_buffers = 0x0;
 499    GLuint i;
 500
 501    /* This makes sure the pipe has the latest scissor, etc values */
 502    st_validate_state( st );
 503
 504    if (mask & BUFFER_BITS_COLOR) {
 505       for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
 506          GLuint b = ctx->DrawBuffer->_ColorDrawBufferIndexes[i];
 507
 508          if (mask & (1 << b)) {
 509             struct gl_renderbuffer *rb
 510                = ctx->DrawBuffer->Attachment[b].Renderbuffer;
 511             struct st_renderbuffer *strb = st_renderbuffer(rb);
 512
 513             if (!strb || !strb->surface)
 514                continue;
 515
 516             if (check_clear_color_with_quad( ctx, rb ))
 517                quad_buffers |= PIPE_CLEAR_COLOR;
 518             else
 519                clear_buffers |= PIPE_CLEAR_COLOR;
 520          }
 521       }
 522    }
 523
 524    if ((mask & BUFFER_BITS_DS) == BUFFER_BITS_DS && depthRb == stencilRb) {
 525       /* clearing combined depth + stencil */
 526       struct st_renderbuffer *strb = st_renderbuffer(depthRb);
 527
 528       if (strb->surface) {
 529          if (check_clear_depth_stencil_with_quad(ctx, depthRb))
 530             quad_buffers |= PIPE_CLEAR_DEPTHSTENCIL;
 531          else
 532             clear_buffers |= PIPE_CLEAR_DEPTHSTENCIL;
 533       }
 534    }
 535    else {
 536       /* separate depth/stencil clears */
 537       /* I don't think truly separate buffers are actually possible in gallium or hw? */
 538       if (mask & BUFFER_BIT_DEPTH) {
 539          struct st_renderbuffer *strb = st_renderbuffer(depthRb);
 540
 541          if (strb->surface) {
 542             if (check_clear_depth_with_quad(ctx, depthRb,
 543                                             st->clear.enable_ds_separate))
 544                quad_buffers |= PIPE_CLEAR_DEPTH;
 545             else
 546                clear_buffers |= PIPE_CLEAR_DEPTH;
 547          }
 548       }
 549       if (mask & BUFFER_BIT_STENCIL) {
 550          struct st_renderbuffer *strb = st_renderbuffer(stencilRb);
 551
 552          if (strb->surface) {
 553             if (check_clear_stencil_with_quad(ctx, stencilRb,
 554                                               st->clear.enable_ds_separate))
 555                quad_buffers |= PIPE_CLEAR_STENCIL;
 556             else
 557                clear_buffers |= PIPE_CLEAR_STENCIL;
 558          }
 559       }
 560    }
 561
 562    /*
 563     * If we're going to use clear_with_quad() for any reason, use it for
 564     * everything possible.
 565     */
 566    if (quad_buffers) {
 567       quad_buffers |= clear_buffers;
 568       clear_with_quad(ctx,
 569                       quad_buffers & PIPE_CLEAR_COLOR,
 570                       quad_buffers & PIPE_CLEAR_DEPTH,
 571                       quad_buffers & PIPE_CLEAR_STENCIL);
 572    } else if (clear_buffers) {
 573       /* driver cannot know it can clear everything if the buffer
 574        * is a combined depth/stencil buffer but this wasn't actually
 575        * required from the visual. Hence fix this up to avoid potential
 576        * read-modify-write in the driver.
 577        */
 578       union pipe_color_union clearColor;
 579
 580       if ((clear_buffers & PIPE_CLEAR_DEPTHSTENCIL) &&
 581           ((clear_buffers & PIPE_CLEAR_DEPTHSTENCIL) != PIPE_CLEAR_DEPTHSTENCIL) &&
 582           (depthRb == stencilRb) &&
 583           (ctx->DrawBuffer->Visual.depthBits == 0 ||
 584            ctx->DrawBuffer->Visual.stencilBits == 0))
 585          clear_buffers |= PIPE_CLEAR_DEPTHSTENCIL;
 586
 587       if (ctx->DrawBuffer->_ColorDrawBuffers[0]) {
 588          st_translate_color(ctx->Color.ClearColor.f,
 589                             ctx->DrawBuffer->_ColorDrawBuffers[0]->_BaseFormat,
 590                             clearColor.f);
 591       }
 592
 593       st->pipe->clear(st->pipe, clear_buffers, &clearColor,
 594                       ctx->Depth.Clear, ctx->Stencil.Clear);
 595    }
 596    if (mask & BUFFER_BIT_ACCUM)
 597       _mesa_clear_accum_buffer(ctx);
 598 }
 599
 600
 601 void
 602 st_init_clear_functions(struct dd_function_table *functions)
 603 {
 604    functions->Clear = st_Clear;
 605 }