src/mesa/main/clear.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   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 "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 /**
  27  * \file clear.c
  28  * glClearColor, glClearIndex, glClear() functions.
  29  */
  30
  31
  32
  33 #include "glheader.h"
  34 #include "clear.h"
  35 #include "context.h"
  36 #include "enums.h"
  37 #include "fbobject.h"
  38 #include "get.h"
  39 #include "macros.h"
  40 #include "mtypes.h"
  41 #include "state.h"
  42
  43
  44
  45 void GLAPIENTRY
  46 _mesa_ClearIndex( GLfloat c )
  47 {
  48    GET_CURRENT_CONTEXT(ctx);
  49
  50    ctx->Color.ClearIndex = (GLuint) c;
  51 }
  52
  53
  54 /**
  55  * Specify the clear values for the color buffers.
  56  *
  57  * \param red red color component.
  58  * \param green green color component.
  59  * \param blue blue color component.
  60  * \param alpha alpha component.
  61  *
  62  * \sa glClearColor().
  63  */
  64 void GLAPIENTRY
  65 _mesa_ClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )
  66 {
  67    GET_CURRENT_CONTEXT(ctx);
  68
  69    ctx->Color.ClearColor.f[0] = red;
  70    ctx->Color.ClearColor.f[1] = green;
  71    ctx->Color.ClearColor.f[2] = blue;
  72    ctx->Color.ClearColor.f[3] = alpha;
  73 }
  74
  75
  76 /**
  77  * GL_EXT_texture_integer
  78  */
  79 void GLAPIENTRY
  80 _mesa_ClearColorIiEXT(GLint r, GLint g, GLint b, GLint a)
  81 {
  82    GET_CURRENT_CONTEXT(ctx);
  83
  84    ctx->Color.ClearColor.i[0] = r;
  85    ctx->Color.ClearColor.i[1] = g;
  86    ctx->Color.ClearColor.i[2] = b;
  87    ctx->Color.ClearColor.i[3] = a;
  88 }
  89
  90
  91 /**
  92  * GL_EXT_texture_integer
  93  */
  94 void GLAPIENTRY
  95 _mesa_ClearColorIuiEXT(GLuint r, GLuint g, GLuint b, GLuint a)
  96 {
  97    GET_CURRENT_CONTEXT(ctx);
  98
  99    ctx->Color.ClearColor.ui[0] = r;
 100    ctx->Color.ClearColor.ui[1] = g;
 101    ctx->Color.ClearColor.ui[2] = b;
 102    ctx->Color.ClearColor.ui[3] = a;
 103 }
 104
 105
 106 /**
 107  * Returns true if color writes are enabled for the given color attachment.
 108  *
 109  * Beyond checking ColorMask, this uses _mesa_format_has_color_component to
 110  * ignore components that don't actually exist in the format (such as X in
 111  * XRGB).
 112  */
 113 static bool
 114 color_buffer_writes_enabled(const struct gl_context *ctx, unsigned idx)
 115 {
 116    struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[idx];
 117    GLuint c;
 118    GLubyte colorMask = 0;
 119
 120    if (rb) {
 121       for (c = 0; c < 4; c++) {
 122          if (_mesa_format_has_color_component(rb->Format, c))
 123             colorMask |= ctx->Color.ColorMask[idx][c];
 124       }
 125    }
 126
 127    return colorMask != 0;
 128 }
 129
 130
 131 /**
 132  * Clear buffers.
 133  *
 134  * \param mask bit-mask indicating the buffers to be cleared.
 135  *
 136  * Flushes the vertices and verifies the parameter.
 137  * If __struct gl_contextRec::NewState is set then calls _mesa_update_state()
 138  * to update gl_frame_buffer::_Xmin, etc.  If the rasterization mode is set to
 139  * GL_RENDER then requests the driver to clear the buffers, via the
 140  * dd_function_table::Clear callback.
 141  */
 142 void GLAPIENTRY
 143 _mesa_Clear( GLbitfield mask )
 144 {
 145    GET_CURRENT_CONTEXT(ctx);
 146    FLUSH_VERTICES(ctx, 0);
 147
 148    FLUSH_CURRENT(ctx, 0);
 149
 150    if (MESA_VERBOSE & VERBOSE_API)
 151       _mesa_debug(ctx, "glClear 0x%x\n", mask);
 152
 153    if (mask & ~(GL_COLOR_BUFFER_BIT |
 154                 GL_DEPTH_BUFFER_BIT |
 155                 GL_STENCIL_BUFFER_BIT |
 156                 GL_ACCUM_BUFFER_BIT)) {
 157       /* invalid bit set */
 158       _mesa_error( ctx, GL_INVALID_VALUE, "glClear(0x%x)", mask);
 159       return;
 160    }
 161
 162    /* Accumulation buffers were removed in core contexts, and they never
 163     * existed in OpenGL ES.
 164     */
 165    if ((mask & GL_ACCUM_BUFFER_BIT) != 0
 166        && (ctx->API == API_OPENGL_CORE || _mesa_is_gles(ctx))) {
 167       _mesa_error( ctx, GL_INVALID_VALUE, "glClear(GL_ACCUM_BUFFER_BIT)");
 168       return;
 169    }
 170
 171    if (ctx->NewState) {
 172       _mesa_update_state( ctx );        /* update _Xmin, etc */
 173    }
 174
 175    if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 176       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
 177                   "glClear(incomplete framebuffer)");
 178       return;
 179    }
 180
 181    if (ctx->RasterDiscard)
 182       return;
 183
 184    if (ctx->RenderMode == GL_RENDER) {
 185       GLbitfield bufferMask;
 186
 187       /* don't clear depth buffer if depth writing disabled */
 188       if (!ctx->Depth.Mask)
 189          mask &= ~GL_DEPTH_BUFFER_BIT;
 190
 191       /* Build the bitmask to send to device driver's Clear function.
 192        * Note that the GL_COLOR_BUFFER_BIT flag will expand to 0, 1, 2 or 4
 193        * of the BUFFER_BIT_FRONT/BACK_LEFT/RIGHT flags, or one of the
 194        * BUFFER_BIT_COLORn flags.
 195        */
 196       bufferMask = 0;
 197       if (mask & GL_COLOR_BUFFER_BIT) {
 198          GLuint i;
 199          for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
 200             GLint buf = ctx->DrawBuffer->_ColorDrawBufferIndexes[i];
 201
 202             if (buf >= 0 && color_buffer_writes_enabled(ctx, i)) {
 203                bufferMask |= 1 << buf;
 204             }
 205          }
 206       }
 207
 208       if ((mask & GL_DEPTH_BUFFER_BIT)
 209           && ctx->DrawBuffer->Visual.haveDepthBuffer) {
 210          bufferMask |= BUFFER_BIT_DEPTH;
 211       }
 212
 213       if ((mask & GL_STENCIL_BUFFER_BIT)
 214           && ctx->DrawBuffer->Visual.haveStencilBuffer) {
 215          bufferMask |= BUFFER_BIT_STENCIL;
 216       }
 217
 218       if ((mask & GL_ACCUM_BUFFER_BIT)
 219           && ctx->DrawBuffer->Visual.haveAccumBuffer) {
 220          bufferMask |= BUFFER_BIT_ACCUM;
 221       }
 222
 223       assert(ctx->Driver.Clear);
 224       ctx->Driver.Clear(ctx, bufferMask);
 225    }
 226 }
 227
 228
 229 /** Returned by make_color_buffer_mask() for errors */
 230 #define INVALID_MASK ~0x0U
 231
 232
 233 /**
 234  * Convert the glClearBuffer 'drawbuffer' parameter into a bitmask of
 235  * BUFFER_BIT_x values.
 236  * Return INVALID_MASK if the drawbuffer value is invalid.
 237  */
 238 static GLbitfield
 239 make_color_buffer_mask(struct gl_context *ctx, GLint drawbuffer)
 240 {
 241    const struct gl_renderbuffer_attachment *att = ctx->DrawBuffer->Attachment;
 242    GLbitfield mask = 0x0;
 243
 244    /* From the GL 4.0 specification:
 245     *   If buffer is COLOR, a particular draw buffer DRAW_BUFFERi is
 246     *   specified by passing i as the parameter drawbuffer, and value
 247     *   points to a four-element vector specifying the R, G, B, and A
 248     *   color to clear that draw buffer to. If the draw buffer is one
 249     *   of FRONT, BACK, LEFT, RIGHT, or FRONT_AND_BACK, identifying
 250     *   multiple buffers, each selected buffer is cleared to the same
 251     *   value.
 252     *
 253     * Note that "drawbuffer" and "draw buffer" have different meaning.
 254     * "drawbuffer" specifies DRAW_BUFFERi, while "draw buffer" is what's
 255     * assigned to DRAW_BUFFERi. It could be COLOR_ATTACHMENT0, FRONT, BACK,
 256     * etc.
 257     */
 258    if (drawbuffer < 0 || drawbuffer >= (GLint)ctx->Const.MaxDrawBuffers) {
 259       return INVALID_MASK;
 260    }
 261
 262    switch (ctx->DrawBuffer->ColorDrawBuffer[drawbuffer]) {
 263    case GL_FRONT:
 264       if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 265          mask |= BUFFER_BIT_FRONT_LEFT;
 266       if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
 267          mask |= BUFFER_BIT_FRONT_RIGHT;
 268       break;
 269    case GL_BACK:
 270       /* For GLES contexts with a single buffered configuration, we actually
 271        * only have a front renderbuffer, so any clear calls to GL_BACK should
 272        * affect that buffer. See draw_buffer_enum_to_bitmask for details.
 273        */
 274       if (_mesa_is_gles(ctx))
 275          if (!ctx->DrawBuffer->Visual.doubleBufferMode)
 276             if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 277                mask |= BUFFER_BIT_FRONT_LEFT;
 278       if (att[BUFFER_BACK_LEFT].Renderbuffer)
 279          mask |= BUFFER_BIT_BACK_LEFT;
 280       if (att[BUFFER_BACK_RIGHT].Renderbuffer)
 281          mask |= BUFFER_BIT_BACK_RIGHT;
 282       break;
 283    case GL_LEFT:
 284       if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 285          mask |= BUFFER_BIT_FRONT_LEFT;
 286       if (att[BUFFER_BACK_LEFT].Renderbuffer)
 287          mask |= BUFFER_BIT_BACK_LEFT;
 288       break;
 289    case GL_RIGHT:
 290       if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
 291          mask |= BUFFER_BIT_FRONT_RIGHT;
 292       if (att[BUFFER_BACK_RIGHT].Renderbuffer)
 293          mask |= BUFFER_BIT_BACK_RIGHT;
 294       break;
 295    case GL_FRONT_AND_BACK:
 296       if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 297          mask |= BUFFER_BIT_FRONT_LEFT;
 298       if (att[BUFFER_BACK_LEFT].Renderbuffer)
 299          mask |= BUFFER_BIT_BACK_LEFT;
 300       if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
 301          mask |= BUFFER_BIT_FRONT_RIGHT;
 302       if (att[BUFFER_BACK_RIGHT].Renderbuffer)
 303          mask |= BUFFER_BIT_BACK_RIGHT;
 304       break;
 305    default:
 306       {
 307          GLint buf = ctx->DrawBuffer->_ColorDrawBufferIndexes[drawbuffer];
 308
 309          if (buf >= 0 && att[buf].Renderbuffer) {
 310             mask |= 1 << buf;
 311          }
 312       }
 313    }
 314
 315    return mask;
 316 }
 317
 318
 319
 320 /**
 321  * New in GL 3.0
 322  * Clear signed integer color buffer or stencil buffer (not depth).
 323  */
 324 void GLAPIENTRY
 325 _mesa_ClearBufferiv(GLenum buffer, GLint drawbuffer, const GLint *value)
 326 {
 327    GET_CURRENT_CONTEXT(ctx);
 328    FLUSH_VERTICES(ctx, 0);
 329
 330    FLUSH_CURRENT(ctx, 0);
 331
 332    if (ctx->NewState) {
 333       _mesa_update_state( ctx );
 334    }
 335
 336    switch (buffer) {
 337    case GL_STENCIL:
 338       /* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
 339        *
 340        *     "ClearBuffer generates an INVALID VALUE error if buffer is
 341        *     COLOR and drawbuffer is less than zero, or greater than the
 342        *     value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
 343        *     STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
 344        */
 345       if (drawbuffer != 0) {
 346          _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferiv(drawbuffer=%d)",
 347                      drawbuffer);
 348          return;
 349       }
 350       else if (ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer
 351                && !ctx->RasterDiscard) {
 352          /* Save current stencil clear value, set to 'value', do the
 353           * stencil clear and restore the clear value.
 354           * XXX in the future we may have a new ctx->Driver.ClearBuffer()
 355           * hook instead.
 356           */
 357          const GLuint clearSave = ctx->Stencil.Clear;
 358          ctx->Stencil.Clear = *value;
 359          ctx->Driver.Clear(ctx, BUFFER_BIT_STENCIL);
 360          ctx->Stencil.Clear = clearSave;
 361       }
 362       break;
 363    case GL_COLOR:
 364       {
 365          const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
 366          if (mask == INVALID_MASK) {
 367             _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferiv(drawbuffer=%d)",
 368                         drawbuffer);
 369             return;
 370          }
 371          else if (mask && !ctx->RasterDiscard) {
 372             union gl_color_union clearSave;
 373
 374             /* save color */
 375             clearSave = ctx->Color.ClearColor;
 376             /* set color */
 377             COPY_4V(ctx->Color.ClearColor.i, value);
 378             /* clear buffer(s) */
 379             ctx->Driver.Clear(ctx, mask);
 380             /* restore color */
 381             ctx->Color.ClearColor = clearSave;
 382          }
 383       }
 384       break;
 385    default:
 386       /* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
 387        * of the OpenGL 4.5 spec states:
 388        *
 389        *    "An INVALID_ENUM error is generated by ClearBufferiv and
 390        *     ClearNamedFramebufferiv if buffer is not COLOR or STENCIL."
 391        */
 392       _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferiv(buffer=%s)",
 393                   _mesa_enum_to_string(buffer));
 394       return;
 395    }
 396 }
 397
 398
 399 /**
 400  * The ClearBuffer framework is so complicated and so riddled with the
 401  * assumption that the framebuffer is bound that, for now, we will just fake
 402  * direct state access clearing for the user.
 403  */
 404 void GLAPIENTRY
 405 _mesa_ClearNamedFramebufferiv(GLuint framebuffer, GLenum buffer,
 406                               GLint drawbuffer, const GLint *value)
 407 {
 408    GLint oldfb;
 409
 410    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 411    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 412    _mesa_ClearBufferiv(buffer, drawbuffer, value);
 413    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 414 }
 415
 416
 417 /**
 418  * New in GL 3.0
 419  * Clear unsigned integer color buffer (not depth, not stencil).
 420  */
 421 void GLAPIENTRY
 422 _mesa_ClearBufferuiv(GLenum buffer, GLint drawbuffer, const GLuint *value)
 423 {
 424    GET_CURRENT_CONTEXT(ctx);
 425
 426    FLUSH_VERTICES(ctx, 0);
 427    FLUSH_CURRENT(ctx, 0);
 428
 429    if (ctx->NewState) {
 430       _mesa_update_state( ctx );
 431    }
 432
 433    switch (buffer) {
 434    case GL_COLOR:
 435       {
 436          const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
 437          if (mask == INVALID_MASK) {
 438             _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferuiv(drawbuffer=%d)",
 439                         drawbuffer);
 440             return;
 441          }
 442          else if (mask && !ctx->RasterDiscard) {
 443             union gl_color_union clearSave;
 444
 445             /* save color */
 446             clearSave = ctx->Color.ClearColor;
 447             /* set color */
 448             COPY_4V(ctx->Color.ClearColor.ui, value);
 449             /* clear buffer(s) */
 450             ctx->Driver.Clear(ctx, mask);
 451             /* restore color */
 452             ctx->Color.ClearColor = clearSave;
 453          }
 454       }
 455       break;
 456    default:
 457       /* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
 458        * of the OpenGL 4.5 spec states:
 459        *
 460        *    "An INVALID_ENUM error is generated by ClearBufferuiv and
 461        *     ClearNamedFramebufferuiv if buffer is not COLOR."
 462        */
 463       _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferuiv(buffer=%s)",
 464                   _mesa_enum_to_string(buffer));
 465       return;
 466    }
 467 }
 468
 469
 470 /**
 471  * The ClearBuffer framework is so complicated and so riddled with the
 472  * assumption that the framebuffer is bound that, for now, we will just fake
 473  * direct state access clearing for the user.
 474  */
 475 void GLAPIENTRY
 476 _mesa_ClearNamedFramebufferuiv(GLuint framebuffer, GLenum buffer,
 477                                GLint drawbuffer, const GLuint *value)
 478 {
 479    GLint oldfb;
 480
 481    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 482    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 483    _mesa_ClearBufferuiv(buffer, drawbuffer, value);
 484    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 485 }
 486
 487
 488 /**
 489  * New in GL 3.0
 490  * Clear fixed-pt or float color buffer or depth buffer (not stencil).
 491  */
 492 void GLAPIENTRY
 493 _mesa_ClearBufferfv(GLenum buffer, GLint drawbuffer, const GLfloat *value)
 494 {
 495    GET_CURRENT_CONTEXT(ctx);
 496
 497    FLUSH_VERTICES(ctx, 0);
 498    FLUSH_CURRENT(ctx, 0);
 499
 500    if (ctx->NewState) {
 501       _mesa_update_state( ctx );
 502    }
 503
 504    switch (buffer) {
 505    case GL_DEPTH:
 506       /* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
 507        *
 508        *     "ClearBuffer generates an INVALID VALUE error if buffer is
 509        *     COLOR and drawbuffer is less than zero, or greater than the
 510        *     value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
 511        *     STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
 512        */
 513       if (drawbuffer != 0) {
 514          _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfv(drawbuffer=%d)",
 515                      drawbuffer);
 516          return;
 517       }
 518       else if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer
 519                && !ctx->RasterDiscard) {
 520          /* Save current depth clear value, set to 'value', do the
 521           * depth clear and restore the clear value.
 522           * XXX in the future we may have a new ctx->Driver.ClearBuffer()
 523           * hook instead.
 524           */
 525          const GLclampd clearSave = ctx->Depth.Clear;
 526          ctx->Depth.Clear = *value;
 527          ctx->Driver.Clear(ctx, BUFFER_BIT_DEPTH);
 528          ctx->Depth.Clear = clearSave;
 529       }
 530       /* clear depth buffer to value */
 531       break;
 532    case GL_COLOR:
 533       {
 534          const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
 535          if (mask == INVALID_MASK) {
 536             _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfv(drawbuffer=%d)",
 537                         drawbuffer);
 538             return;
 539          }
 540          else if (mask && !ctx->RasterDiscard) {
 541             union gl_color_union clearSave;
 542
 543             /* save color */
 544             clearSave = ctx->Color.ClearColor;
 545             /* set color */
 546             COPY_4V(ctx->Color.ClearColor.f, value);
 547             /* clear buffer(s) */
 548             ctx->Driver.Clear(ctx, mask);
 549             /* restore color */
 550             ctx->Color.ClearColor = clearSave;
 551          }
 552       }
 553       break;
 554    default:
 555       /* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
 556        * of the OpenGL 4.5 spec states:
 557        *
 558        *    "An INVALID_ENUM error is generated by ClearBufferfv and
 559        *     ClearNamedFramebufferfv if buffer is not COLOR or DEPTH."
 560        */
 561       _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferfv(buffer=%s)",
 562                   _mesa_enum_to_string(buffer));
 563       return;
 564    }
 565 }
 566
 567
 568 /**
 569  * The ClearBuffer framework is so complicated and so riddled with the
 570  * assumption that the framebuffer is bound that, for now, we will just fake
 571  * direct state access clearing for the user.
 572  */
 573 void GLAPIENTRY
 574 _mesa_ClearNamedFramebufferfv(GLuint framebuffer, GLenum buffer,
 575                               GLint drawbuffer, const GLfloat *value)
 576 {
 577    GLint oldfb;
 578
 579    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 580    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 581    _mesa_ClearBufferfv(buffer, drawbuffer, value);
 582    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 583 }
 584
 585
 586 /**
 587  * New in GL 3.0
 588  * Clear depth/stencil buffer only.
 589  */
 590 void GLAPIENTRY
 591 _mesa_ClearBufferfi(GLenum buffer, GLint drawbuffer,
 592                     GLfloat depth, GLint stencil)
 593 {
 594    GET_CURRENT_CONTEXT(ctx);
 595    GLbitfield mask = 0;
 596
 597    FLUSH_VERTICES(ctx, 0);
 598    FLUSH_CURRENT(ctx, 0);
 599
 600    if (buffer != GL_DEPTH_STENCIL) {
 601       _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferfi(buffer=%s)",
 602                   _mesa_enum_to_string(buffer));
 603       return;
 604    }
 605
 606    /* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
 607     *
 608     *     "ClearBuffer generates an INVALID VALUE error if buffer is
 609     *     COLOR and drawbuffer is less than zero, or greater than the
 610     *     value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
 611     *     STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
 612     */
 613    if (drawbuffer != 0) {
 614       _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfi(drawbuffer=%d)",
 615                   drawbuffer);
 616       return;
 617    }
 618
 619    if (ctx->RasterDiscard)
 620       return;
 621
 622    if (ctx->NewState) {
 623       _mesa_update_state( ctx );
 624    }
 625
 626    if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer)
 627       mask |= BUFFER_BIT_DEPTH;
 628    if (ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer)
 629       mask |= BUFFER_BIT_STENCIL;
 630
 631    if (mask) {
 632       /* save current clear values */
 633       const GLclampd clearDepthSave = ctx->Depth.Clear;
 634       const GLuint clearStencilSave = ctx->Stencil.Clear;
 635
 636       /* set new clear values */
 637       ctx->Depth.Clear = depth;
 638       ctx->Stencil.Clear = stencil;
 639
 640       /* clear buffers */
 641       ctx->Driver.Clear(ctx, mask);
 642
 643       /* restore */
 644       ctx->Depth.Clear = clearDepthSave;
 645       ctx->Stencil.Clear = clearStencilSave;
 646    }
 647 }
 648
 649
 650 /**
 651  * The ClearBuffer framework is so complicated and so riddled with the
 652  * assumption that the framebuffer is bound that, for now, we will just fake
 653  * direct state access clearing for the user.
 654  */
 655 void GLAPIENTRY
 656 _mesa_ClearNamedFramebufferfi(GLuint framebuffer, GLenum buffer,
 657                               GLint drawbuffer, GLfloat depth, GLint stencil)
 658 {
 659    GLint oldfb;
 660
 661    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 662    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 663    _mesa_ClearBufferfi(buffer, drawbuffer, depth, stencil);
 664    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 665 }