src/mesa/state_tracker/st_cb_clear.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * 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
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28  /*
  29   * Authors:
  30   *   Keith Whitwell <keith@tungstengraphics.com>
  31   *   Brian Paul
  32   */
  33
  34 #include "main/glheader.h"
  35 #include "main/macros.h"
  36 #include "shader/prog_instruction.h"
  37 #include "st_atom.h"
  38 #include "st_cache.h"
  39 #include "st_context.h"
  40 #include "st_cb_clear.h"
  41 #include "st_cb_fbo.h"
  42 #include "st_draw.h"
  43 #include "st_program.h"
  44 #include "st_public.h"
  45
  46 #include "pipe/p_context.h"
  47 #include "pipe/p_state.h"
  48 #include "pipe/p_defines.h"
  49 #include "pipe/p_winsys.h"
  50
  51 #include "pipe/tgsi/mesa/mesa_to_tgsi.h"
  52
  53 #include "vf/vf.h"
  54
  55
  56
  57
  58 static GLuint
  59 color_value(GLuint pipeFormat, const GLfloat color[4])
  60 {
  61    GLubyte r, g, b, a;
  62
  63    UNCLAMPED_FLOAT_TO_UBYTE(r, color[0]);
  64    UNCLAMPED_FLOAT_TO_UBYTE(g, color[1]);
  65    UNCLAMPED_FLOAT_TO_UBYTE(b, color[2]);
  66    UNCLAMPED_FLOAT_TO_UBYTE(a, color[3]);
  67
  68    switch (pipeFormat) {
  69    case PIPE_FORMAT_U_R8_G8_B8_A8:
  70       return (r << 24) | (g << 16) | (b << 8) | a;
  71    case PIPE_FORMAT_U_A8_R8_G8_B8:
  72       return (a << 24) | (r << 16) | (g << 8) | b;
  73    case PIPE_FORMAT_U_R5_G6_B5:
  74       return ((r & 0xf8) << 8) | ((g & 0xfc) << 3) | (b >> 3);
  75    default:
  76       return 0;
  77    }
  78 }
  79
  80
  81 static GLuint
  82 depth_value(GLuint pipeFormat, GLfloat value)
  83 {
  84    GLuint val;
  85    switch (pipeFormat) {
  86    case PIPE_FORMAT_U_Z16:
  87       val = (GLuint) (value * 0xffffff);
  88       break;
  89    case PIPE_FORMAT_U_Z32:
  90       val = (GLuint) (value * 0xffffffff);
  91       break;
  92    case PIPE_FORMAT_S8_Z24:
  93    /*case PIPE_FORMAT_Z24_S8:*/
  94       val = (GLuint) (value * 0xffffff);
  95       break;
  96    default:
  97       val = 0;
  98       assert(0);
  99    }
 100    return val;
 101 }
 102
 103
 104 static GLboolean
 105 is_depth_stencil_format(GLuint pipeFormat)
 106 {
 107    switch (pipeFormat) {
 108    case PIPE_FORMAT_S8_Z24:
 109    /*case PIPE_FORMAT_Z24_S8:*/
 110       return GL_TRUE;
 111    default:
 112       return GL_FALSE;
 113    }
 114 }
 115
 116
 117
 118 /**
 119  * Create a simple fragment shader that just passes through the fragment color.
 120  */
 121 static struct st_fragment_program *
 122 make_frag_shader(struct st_context *st)
 123 {
 124    static const GLuint outputMapping[] = { 1, 0 };
 125    GLcontext *ctx = st->ctx;
 126    struct st_fragment_program *stfp;
 127    struct gl_program *p;
 128    GLboolean b;
 129    GLuint interpMode[16];
 130    GLuint i;
 131
 132    /* XXX temporary */
 133    for (i = 0; i < 16; i++)
 134       interpMode[i] = TGSI_INTERPOLATE_LINEAR;
 135
 136    p = ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);
 137    if (!p)
 138       return NULL;
 139
 140    p->NumInstructions = 2;
 141    p->Instructions = _mesa_alloc_instructions(2);
 142    if (!p->Instructions) {
 143       ctx->Driver.DeleteProgram(ctx, p);
 144       return NULL;
 145    }
 146    _mesa_init_instructions(p->Instructions, 2);
 147    /* MOV result.color, fragment.color; */
 148    p->Instructions[0].Opcode = OPCODE_MOV;
 149    p->Instructions[0].DstReg.File = PROGRAM_OUTPUT;
 150    p->Instructions[0].DstReg.Index = FRAG_RESULT_COLR;
 151    p->Instructions[0].SrcReg[0].File = PROGRAM_INPUT;
 152    p->Instructions[0].SrcReg[0].Index = FRAG_ATTRIB_COL0;
 153    /* END; */
 154    p->Instructions[1].Opcode = OPCODE_END;
 155
 156    p->InputsRead = FRAG_BIT_COL0;
 157    p->OutputsWritten = (1 << FRAG_RESULT_COLR);
 158
 159    stfp = (struct st_fragment_program *) p;
 160    /* compile into tgsi format */
 161    b = tgsi_mesa_compile_fp_program(&stfp->Base, NULL, interpMode,
 162                                     outputMapping,
 163                                     stfp->tokens, ST_FP_MAX_TOKENS);
 164    assert(b);
 165
 166    return stfp;
 167 }
 168
 169
 170 /**
 171  * Create a simple vertex shader that just passes through the
 172  * vertex position and color.
 173  */
 174 static struct st_vertex_program *
 175 make_vertex_shader(struct st_context *st)
 176 {
 177    /* Map VERT_ATTRIB_POS to 0, VERT_ATTRIB_COLOR0 to 1 */
 178    static const GLuint inputMapping[4] = { 0, 0, 0, 1 };
 179    /* Map VERT_RESULT_HPOS to 0, VERT_RESULT_COL0 to 1 */
 180    static const GLuint outputMapping[2] = { 0, 1 };
 181
 182    GLcontext *ctx = st->ctx;
 183    struct st_vertex_program *stvp;
 184    struct gl_program *p;
 185    GLboolean b;
 186
 187    p = ctx->Driver.NewProgram(ctx, GL_VERTEX_PROGRAM_ARB, 0);
 188    if (!p)
 189       return NULL;
 190
 191    p->NumInstructions = 3;
 192    p->Instructions = _mesa_alloc_instructions(3);
 193    if (!p->Instructions) {
 194       ctx->Driver.DeleteProgram(ctx, p);
 195       return NULL;
 196    }
 197    _mesa_init_instructions(p->Instructions, 3);
 198    /* MOV result.pos, vertex.pos; */
 199    p->Instructions[0].Opcode = OPCODE_MOV;
 200    p->Instructions[0].DstReg.File = PROGRAM_OUTPUT;
 201    p->Instructions[0].DstReg.Index = VERT_RESULT_HPOS;
 202    p->Instructions[0].SrcReg[0].File = PROGRAM_INPUT;
 203    p->Instructions[0].SrcReg[0].Index = VERT_ATTRIB_POS;
 204    /* MOV result.color, vertex.color; */
 205    p->Instructions[1].Opcode = OPCODE_MOV;
 206    p->Instructions[1].DstReg.File = PROGRAM_OUTPUT;
 207    p->Instructions[1].DstReg.Index = VERT_RESULT_COL0;
 208    p->Instructions[1].SrcReg[0].File = PROGRAM_INPUT;
 209    p->Instructions[1].SrcReg[0].Index = VERT_ATTRIB_COLOR0;
 210    /* END; */
 211    p->Instructions[2].Opcode = OPCODE_END;
 212
 213    p->InputsRead = VERT_BIT_POS | VERT_BIT_COLOR0;
 214    p->OutputsWritten = ((1 << VERT_RESULT_COL0) |
 215                         (1 << VERT_RESULT_HPOS));
 216
 217    stvp = (struct st_vertex_program *) p;
 218    /* compile into tgsi format */
 219    b = tgsi_mesa_compile_vp_program(&stvp->Base,
 220                                     inputMapping,
 221                                     outputMapping,
 222                                     stvp->tokens, ST_FP_MAX_TOKENS);
 223    assert(b);
 224
 225    return stvp;
 226 }
 227
 228
 229
 230 /**
 231  * Draw a screen-aligned quadrilateral.
 232  * Coords are window coords with y=0=bottom.  These coords will be transformed
 233  * by the vertex shader and viewport transform (which will flip Y if needed).
 234  */
 235 static void
 236 draw_quad(GLcontext *ctx,
 237           float x0, float y0, float x1, float y1, GLfloat z,
 238           const GLfloat color[4])
 239 {
 240    static const GLuint attribs[2] = {
 241       0, /* pos */
 242       3  /* color */
 243    };
 244    GLfloat verts[4][2][4]; /* four verts, two attribs, XYZW */
 245    GLuint i;
 246
 247    /* positions */
 248    verts[0][0][0] = x0;
 249    verts[0][0][1] = y0;
 250
 251    verts[1][0][0] = x1;
 252    verts[1][0][1] = y0;
 253
 254    verts[2][0][0] = x1;
 255    verts[2][0][1] = y1;
 256
 257    verts[3][0][0] = x0;
 258    verts[3][0][1] = y1;
 259
 260    /* same for all verts: */
 261    for (i = 0; i < 4; i++) {
 262       verts[i][0][2] = z;
 263       verts[i][0][3] = 1.0;
 264       verts[i][1][0] = color[0];
 265       verts[i][1][1] = color[1];
 266       verts[i][1][2] = color[2];
 267       verts[i][1][3] = color[3];
 268    }
 269
 270    st_draw_vertices(ctx, PIPE_PRIM_QUADS, 4, (float *) verts, 2, attribs);
 271 }
 272
 273
 274
 275 /**
 276  * Do glClear by drawing a quadrilateral.
 277  * The vertices of the quad will be computed from the
 278  * ctx->DrawBuffer->_X/Ymin/max fields.
 279  */
 280 static void
 281 clear_with_quad(GLcontext *ctx,
 282                 GLboolean color, GLboolean depth, GLboolean stencil)
 283 {
 284    struct st_context *st = ctx->st;
 285    struct pipe_context *pipe = ctx->st->pipe;
 286    const GLfloat x0 = ctx->DrawBuffer->_Xmin;
 287    const GLfloat y0 = ctx->DrawBuffer->_Ymin;
 288    const GLfloat x1 = ctx->DrawBuffer->_Xmax;
 289    const GLfloat y1 = ctx->DrawBuffer->_Ymax;
 290
 291    /* alpha state: disabled */
 292    {
 293       struct pipe_alpha_test_state alpha_test;
 294       memset(&alpha_test, 0, sizeof(alpha_test));
 295       pipe->set_alpha_test_state(pipe, &alpha_test);
 296    }
 297
 298    /* blend state: RGBA masking */
 299    {
 300       struct pipe_blend_state blend;
 301       const struct pipe_blend_state *state;
 302       memset(&blend, 0, sizeof(blend));
 303       if (color) {
 304          if (ctx->Color.ColorMask[0])
 305             blend.colormask |= PIPE_MASK_R;
 306          if (ctx->Color.ColorMask[1])
 307             blend.colormask |= PIPE_MASK_G;
 308          if (ctx->Color.ColorMask[2])
 309             blend.colormask |= PIPE_MASK_B;
 310          if (ctx->Color.ColorMask[3])
 311             blend.colormask |= PIPE_MASK_A;
 312          if (st->ctx->Color.DitherFlag)
 313             blend.dither = 1;
 314       }
 315       state = st_cached_blend_state(st, &blend);
 316       pipe->bind_blend_state(pipe, state);
 317    }
 318
 319    /* depth_stencil state: always pass/set to ref value */
 320    {
 321       struct pipe_depth_stencil_state depth_stencil;
 322       struct pipe_depth_stencil_state *cached;
 323       memset(&depth_stencil, 0, sizeof(depth_stencil));
 324       if (depth) {
 325          depth_stencil.depth.enabled = 1;
 326          depth_stencil.depth.writemask = 1;
 327          depth_stencil.depth.func = PIPE_FUNC_ALWAYS;
 328       }
 329
 330       if (stencil) {
 331          depth_stencil.stencil.front_enabled = 1;
 332          depth_stencil.stencil.front_func = PIPE_FUNC_ALWAYS;
 333          depth_stencil.stencil.front_fail_op = PIPE_STENCIL_OP_REPLACE;
 334          depth_stencil.stencil.front_zpass_op = PIPE_STENCIL_OP_REPLACE;
 335          depth_stencil.stencil.front_zfail_op = PIPE_STENCIL_OP_REPLACE;
 336          depth_stencil.stencil.ref_value[0] = ctx->Stencil.Clear;
 337          depth_stencil.stencil.value_mask[0] = 0xff;
 338          depth_stencil.stencil.write_mask[0] = ctx->Stencil.WriteMask[0] & 0xff;
 339       }
 340       cached =
 341          st_cached_depth_stencil_state(ctx->st, &depth_stencil);
 342       pipe->bind_depth_stencil_state(pipe, cached);
 343    }
 344
 345    /* setup state: nothing */
 346    {
 347       struct pipe_rasterizer_state raster;
 348       const struct pipe_rasterizer_state *cached;
 349       memset(&raster, 0, sizeof(raster));
 350 #if 0
 351       /* don't do per-pixel scissor; we'll just draw a PIPE_PRIM_QUAD
 352        * that matches the scissor bounds.
 353        */
 354       if (ctx->Scissor.Enabled)
 355          raster.scissor = 1;
 356 #endif
 357       cached = st_cached_rasterizer_state(ctx->st, &raster);
 358       pipe->bind_rasterizer_state(pipe, cached);
 359    }
 360
 361    /* fragment shader state: color pass-through program */
 362    {
 363       static struct st_fragment_program *stfp = NULL;
 364       struct pipe_shader_state fs;
 365       const struct pipe_shader_state *cached;
 366       if (!stfp) {
 367          stfp = make_frag_shader(st);
 368       }
 369       memset(&fs, 0, sizeof(fs));
 370       fs.inputs_read = tgsi_mesa_translate_fragment_input_mask(stfp->Base.Base.InputsRead);
 371       fs.outputs_written = tgsi_mesa_translate_fragment_output_mask(stfp->Base.Base.OutputsWritten);
 372       fs.tokens = &stfp->tokens[0];
 373       cached = st_cached_fs_state(st, &fs);
 374       pipe->bind_fs_state(pipe, cached);
 375    }
 376
 377    /* vertex shader state: color/position pass-through */
 378    {
 379       static struct st_vertex_program *stvp = NULL;
 380       struct pipe_shader_state vs;
 381       const struct pipe_shader_state *cached;
 382       if (!stvp) {
 383          stvp = make_vertex_shader(st);
 384       }
 385       memset(&vs, 0, sizeof(vs));
 386       vs.inputs_read = stvp->Base.Base.InputsRead;
 387       vs.outputs_written = stvp->Base.Base.OutputsWritten;
 388       vs.tokens = &stvp->tokens[0];
 389       cached = st_cached_vs_state(st, &vs);
 390       pipe->bind_vs_state(pipe, cached);
 391    }
 392
 393    /* viewport state: viewport matching window dims */
 394    {
 395       const float width = ctx->DrawBuffer->Width;
 396       const float height = ctx->DrawBuffer->Height;
 397       struct pipe_viewport_state vp;
 398       vp.scale[0] =  0.5 * width;
 399       vp.scale[1] = -0.5 * height;
 400       vp.scale[2] = 0.5;
 401       vp.scale[3] = 1.0;
 402       vp.translate[0] = 0.5 * width;
 403       vp.translate[1] = 0.5 * height;
 404       vp.translate[2] = 0.5;
 405       vp.translate[3] = 0.0;
 406       pipe->set_viewport_state(pipe, &vp);
 407    }
 408
 409    /* draw quad matching scissor rect (XXX verify coord round-off) */
 410    draw_quad(ctx, x0, y0, x1, y1, ctx->Depth.Clear, ctx->Color.ClearColor);
 411
 412    /* Restore pipe state */
 413    pipe->set_alpha_test_state(pipe, &st->state.alpha_test);
 414    pipe->bind_blend_state(pipe, st->state.blend);
 415    pipe->bind_depth_stencil_state(pipe, st->state.depth_stencil);
 416    pipe->bind_fs_state(pipe, st->state.fs);
 417    pipe->bind_vs_state(pipe, st->state.vs);
 418    pipe->bind_rasterizer_state(pipe, st->state.rasterizer);
 419    pipe->set_viewport_state(pipe, &ctx->st->state.viewport);
 420    /* OR:
 421    st_invalidate_state(ctx, _NEW_COLOR | _NEW_DEPTH | _NEW_STENCIL);
 422    */
 423 }
 424
 425
 426 /**
 427  * Determine if we need to clear the depth buffer by drawing a quad.
 428  */
 429 static INLINE GLboolean
 430 check_clear_color_with_quad(GLcontext *ctx)
 431 {
 432    return !(ctx->Color.ColorMask[0] &&
 433             ctx->Color.ColorMask[1] &&
 434             ctx->Color.ColorMask[2] &&
 435             ctx->Color.ColorMask[3] &&
 436             !ctx->Scissor.Enabled);
 437 }
 438
 439
 440 /**
 441  * Determine if we need to clear the depth buffer by drawing a quad.
 442  */
 443 static INLINE GLboolean
 444 check_clear_depth_with_quad(GLcontext *ctx, struct gl_renderbuffer *rb)
 445 {
 446    const struct st_renderbuffer *strb = st_renderbuffer(rb);
 447    const GLboolean isDS = is_depth_stencil_format(strb->surface->format);
 448    return  ctx->Scissor.Enabled
 449       || (isDS && ctx->DrawBuffer->Visual.stencilBits > 0);
 450 }
 451
 452
 453 /**
 454  * Determine if we need to clear the stencil buffer by drawing a quad.
 455  */
 456 static INLINE GLboolean
 457 check_clear_stencil_with_quad(GLcontext *ctx, struct gl_renderbuffer *rb)
 458 {
 459    const struct st_renderbuffer *strb = st_renderbuffer(rb);
 460    const GLboolean isDS = is_depth_stencil_format(strb->surface->format);
 461    const GLuint stencilMax = (1 << rb->StencilBits) - 1;
 462    const GLboolean maskStencil
 463       = (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
 464    return maskStencil
 465       || ctx->Scissor.Enabled
 466       || (isDS && ctx->DrawBuffer->Visual.depthBits > 0);
 467 }
 468
 469
 470
 471
 472 static void
 473 clear_color_buffer(GLcontext *ctx, struct gl_renderbuffer *rb)
 474 {
 475    struct st_renderbuffer *strb = st_renderbuffer(rb);
 476
 477    if (ctx->Color.ColorMask[0] &&
 478        ctx->Color.ColorMask[1] &&
 479        ctx->Color.ColorMask[2] &&
 480        ctx->Color.ColorMask[3] &&
 481        !ctx->Scissor.Enabled)
 482    {
 483       /* clear whole buffer w/out masking */
 484       GLuint clearValue
 485          = color_value(strb->surface->format, ctx->Color.ClearColor);
 486       ctx->st->pipe->clear(ctx->st->pipe, strb->surface, clearValue);
 487    }
 488    else {
 489       /* masking or scissoring */
 490       clear_with_quad(ctx, GL_TRUE, GL_FALSE, GL_FALSE);
 491    }
 492 }
 493
 494
 495 static void
 496 clear_accum_buffer(GLcontext *ctx, struct gl_renderbuffer *rb)
 497 {
 498    struct st_renderbuffer *strb = st_renderbuffer(rb);
 499
 500    if (!ctx->Scissor.Enabled) {
 501       /* clear whole buffer w/out masking */
 502       GLuint clearValue
 503          = color_value(strb->surface->format, ctx->Accum.ClearColor);
 504       /* Note that clearValue is 32 bits but the accum buffer will
 505        * typically be 64bpp...
 506        */
 507       ctx->st->pipe->clear(ctx->st->pipe, strb->surface, clearValue);
 508    }
 509    else {
 510       /* scissoring */
 511       /* XXX point framebuffer.cbufs[0] at the accum buffer */
 512       clear_with_quad(ctx, GL_TRUE, GL_FALSE, GL_FALSE);
 513    }
 514 }
 515
 516
 517 static void
 518 clear_depth_buffer(GLcontext *ctx, struct gl_renderbuffer *rb)
 519 {
 520    struct st_renderbuffer *strb = st_renderbuffer(rb);
 521    const GLboolean isDS = is_depth_stencil_format(strb->surface->format);
 522
 523    assert(strb->surface->format);
 524
 525    if (ctx->Scissor.Enabled ||
 526        (isDS && ctx->DrawBuffer->Visual.stencilBits > 0)) {
 527       /* scissoring or we have a combined depth/stencil buffer */
 528       clear_with_quad(ctx, GL_FALSE, GL_TRUE, GL_FALSE);
 529    }
 530    else {
 531       /* simple clear of whole buffer */
 532       GLuint clearValue = depth_value(strb->surface->format, ctx->Depth.Clear);
 533       ctx->st->pipe->clear(ctx->st->pipe, strb->surface, clearValue);
 534    }
 535 }
 536
 537
 538 static void
 539 clear_stencil_buffer(GLcontext *ctx, struct gl_renderbuffer *rb)
 540 {
 541    struct st_renderbuffer *strb = st_renderbuffer(rb);
 542    const GLboolean isDS = is_depth_stencil_format(strb->surface->format);
 543    const GLuint stencilMax = (1 << rb->StencilBits) - 1;
 544    GLboolean maskStencil
 545       = (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
 546
 547    if (maskStencil ||
 548        ctx->Scissor.Enabled ||
 549        (isDS && ctx->DrawBuffer->Visual.depthBits > 0)) {
 550       /* masking or scissoring or combined depth/stencil buffer */
 551       clear_with_quad(ctx, GL_FALSE, GL_FALSE, GL_TRUE);
 552    }
 553    else {
 554       /* simple clear of whole buffer */
 555       GLuint clearValue = ctx->Stencil.Clear;
 556       ctx->st->pipe->clear(ctx->st->pipe, strb->surface, clearValue);
 557    }
 558 }
 559
 560
 561 static void
 562 clear_depth_stencil_buffer(GLcontext *ctx, struct gl_renderbuffer *rb)
 563 {
 564    struct st_renderbuffer *strb = st_renderbuffer(rb);
 565    const GLuint stencilMax = (1 << rb->StencilBits) - 1;
 566    GLboolean maskStencil
 567       = (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
 568
 569    assert(is_depth_stencil_format(strb->surface->format));
 570
 571    if (!maskStencil && !ctx->Scissor.Enabled) {
 572       /* clear whole buffer w/out masking */
 573       GLuint clearValue = depth_value(strb->surface->format, ctx->Depth.Clear);
 574
 575       switch (strb->surface->format) {
 576       case PIPE_FORMAT_S8_Z24:
 577          clearValue |= ctx->Stencil.Clear << 24;
 578          break;
 579 #if 0
 580       case PIPE_FORMAT_Z24_S8:
 581          clearValue = (clearValue << 8) | clearVal;
 582          break;
 583 #endif
 584       default:
 585          assert(0);
 586       }
 587
 588       ctx->st->pipe->clear(ctx->st->pipe, strb->surface, clearValue);
 589    }
 590    else {
 591       /* masking or scissoring */
 592       clear_with_quad(ctx, GL_FALSE, GL_TRUE, GL_TRUE);
 593    }
 594 }
 595
 596
 597
 598 /**
 599  * Called via ctx->Driver.Clear()
 600  * XXX: doesn't pick up the differences between front/back/left/right
 601  * clears.  Need to sort that out...
 602  */
 603 static void st_clear(GLcontext *ctx, GLbitfield mask)
 604 {
 605    static const GLbitfield BUFFER_BITS_DS
 606       = (BUFFER_BIT_DEPTH | BUFFER_BIT_STENCIL);
 607    struct st_context *st = ctx->st;
 608    struct gl_renderbuffer *depthRb
 609       = ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
 610    struct gl_renderbuffer *stencilRb
 611       = ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
 612    GLbitfield cmask = mask & BUFFER_BITS_COLOR;
 613
 614    /* This makes sure the softpipe has the latest scissor, etc values */
 615    st_validate_state( st );
 616
 617    /*
 618     * XXX TO-DO:
 619     * If we're going to use clear_with_quad() for any reason, use it to
 620     * clear as many other buffers as possible.
 621     * As it is now, we sometimes call clear_with_quad() three times to clear
 622     * color/depth/stencil individually...
 623     */
 624
 625    if (cmask) {
 626       GLuint b;
 627       for (b = 0; cmask; b++) {
 628          if (cmask & (1 << b)) {
 629             struct gl_renderbuffer *rb
 630                = ctx->DrawBuffer->Attachment[b].Renderbuffer;
 631             assert(rb);
 632             clear_color_buffer(ctx, rb);
 633             cmask &= ~(1 << b); /* turn off bit */
 634          }
 635          assert(b < BUFFER_COUNT);
 636       }
 637    }
 638
 639    if (mask & BUFFER_BIT_ACCUM) {
 640       clear_accum_buffer(ctx,
 641                      ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer);
 642    }
 643
 644    if ((mask & BUFFER_BITS_DS) == BUFFER_BITS_DS && depthRb == stencilRb) {
 645       /* clearing combined depth + stencil */
 646       clear_depth_stencil_buffer(ctx, depthRb);
 647    }
 648    else {
 649       /* separate depth/stencil clears */
 650       if (mask & BUFFER_BIT_DEPTH) {
 651          clear_depth_buffer(ctx, depthRb);
 652       }
 653       if (mask & BUFFER_BIT_STENCIL) {
 654          clear_stencil_buffer(ctx, stencilRb);
 655       }
 656    }
 657 }
 658
 659
 660 void st_init_clear_functions(struct dd_function_table *functions)
 661 {
 662    functions->Clear = st_clear;
 663 }