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
 119    if (rb) {
 120       for (c = 0; c < 4; c++) {
 121          if (ctx->Color.ColorMask[idx][c] &&
 122              _mesa_format_has_color_component(rb->Format, c)) {
 123             return true;
 124          }
 125       }
 126    }
 127
 128    return false;
 129 }
 130
 131
 132 /**
 133  * Clear buffers.
 134  *
 135  * \param mask bit-mask indicating the buffers to be cleared.
 136  *
 137  * Flushes the vertices and verifies the parameter.
 138  * If __struct gl_contextRec::NewState is set then calls _mesa_update_state()
 139  * to update gl_frame_buffer::_Xmin, etc.  If the rasterization mode is set to
 140  * GL_RENDER then requests the driver to clear the buffers, via the
 141  * dd_function_table::Clear callback.
 142  */
 143 static ALWAYS_INLINE void
 144 clear(struct gl_context *ctx, GLbitfield mask, bool no_error)
 145 {
 146    FLUSH_VERTICES(ctx, 0);
 147    FLUSH_CURRENT(ctx, 0);
 148
 149    if (!no_error) {
 150       if (mask & ~(GL_COLOR_BUFFER_BIT |
 151                    GL_DEPTH_BUFFER_BIT |
 152                    GL_STENCIL_BUFFER_BIT |
 153                    GL_ACCUM_BUFFER_BIT)) {
 154          _mesa_error( ctx, GL_INVALID_VALUE, "glClear(0x%x)", mask);
 155          return;
 156       }
 157
 158       /* Accumulation buffers were removed in core contexts, and they never
 159        * existed in OpenGL ES.
 160        */
 161       if ((mask & GL_ACCUM_BUFFER_BIT) != 0
 162           && (ctx->API == API_OPENGL_CORE || _mesa_is_gles(ctx))) {
 163          _mesa_error( ctx, GL_INVALID_VALUE, "glClear(GL_ACCUM_BUFFER_BIT)");
 164          return;
 165       }
 166    }
 167
 168    if (ctx->NewState) {
 169       _mesa_update_state( ctx );        /* update _Xmin, etc */
 170    }
 171
 172    if (!no_error && ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 173       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
 174                   "glClear(incomplete framebuffer)");
 175       return;
 176    }
 177
 178    if (ctx->RasterDiscard)
 179       return;
 180
 181    if (ctx->RenderMode == GL_RENDER) {
 182       GLbitfield bufferMask;
 183
 184       /* don't clear depth buffer if depth writing disabled */
 185       if (!ctx->Depth.Mask)
 186          mask &= ~GL_DEPTH_BUFFER_BIT;
 187
 188       /* Build the bitmask to send to device driver's Clear function.
 189        * Note that the GL_COLOR_BUFFER_BIT flag will expand to 0, 1, 2 or 4
 190        * of the BUFFER_BIT_FRONT/BACK_LEFT/RIGHT flags, or one of the
 191        * BUFFER_BIT_COLORn flags.
 192        */
 193       bufferMask = 0;
 194       if (mask & GL_COLOR_BUFFER_BIT) {
 195          GLuint i;
 196          for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
 197             GLint buf = ctx->DrawBuffer->_ColorDrawBufferIndexes[i];
 198
 199             if (buf >= 0 && color_buffer_writes_enabled(ctx, i)) {
 200                bufferMask |= 1 << buf;
 201             }
 202          }
 203       }
 204
 205       if ((mask & GL_DEPTH_BUFFER_BIT)
 206           && ctx->DrawBuffer->Visual.haveDepthBuffer) {
 207          bufferMask |= BUFFER_BIT_DEPTH;
 208       }
 209
 210       if ((mask & GL_STENCIL_BUFFER_BIT)
 211           && ctx->DrawBuffer->Visual.haveStencilBuffer) {
 212          bufferMask |= BUFFER_BIT_STENCIL;
 213       }
 214
 215       if ((mask & GL_ACCUM_BUFFER_BIT)
 216           && ctx->DrawBuffer->Visual.haveAccumBuffer) {
 217          bufferMask |= BUFFER_BIT_ACCUM;
 218       }
 219
 220       assert(ctx->Driver.Clear);
 221       ctx->Driver.Clear(ctx, bufferMask);
 222    }
 223 }
 224
 225
 226 void GLAPIENTRY
 227 _mesa_Clear_no_error(GLbitfield mask)
 228 {
 229    GET_CURRENT_CONTEXT(ctx);
 230    clear(ctx, mask, true);
 231 }
 232
 233
 234 void GLAPIENTRY
 235 _mesa_Clear(GLbitfield mask)
 236 {
 237    GET_CURRENT_CONTEXT(ctx);
 238
 239    if (MESA_VERBOSE & VERBOSE_API)
 240       _mesa_debug(ctx, "glClear 0x%x\n", mask);
 241
 242    clear(ctx, mask, false);
 243 }
 244
 245
 246 /** Returned by make_color_buffer_mask() for errors */
 247 #define INVALID_MASK ~0x0U
 248
 249
 250 /**
 251  * Convert the glClearBuffer 'drawbuffer' parameter into a bitmask of
 252  * BUFFER_BIT_x values.
 253  * Return INVALID_MASK if the drawbuffer value is invalid.
 254  */
 255 static GLbitfield
 256 make_color_buffer_mask(struct gl_context *ctx, GLint drawbuffer)
 257 {
 258    const struct gl_renderbuffer_attachment *att = ctx->DrawBuffer->Attachment;
 259    GLbitfield mask = 0x0;
 260
 261    /* From the GL 4.0 specification:
 262     *   If buffer is COLOR, a particular draw buffer DRAW_BUFFERi is
 263     *   specified by passing i as the parameter drawbuffer, and value
 264     *   points to a four-element vector specifying the R, G, B, and A
 265     *   color to clear that draw buffer to. If the draw buffer is one
 266     *   of FRONT, BACK, LEFT, RIGHT, or FRONT_AND_BACK, identifying
 267     *   multiple buffers, each selected buffer is cleared to the same
 268     *   value.
 269     *
 270     * Note that "drawbuffer" and "draw buffer" have different meaning.
 271     * "drawbuffer" specifies DRAW_BUFFERi, while "draw buffer" is what's
 272     * assigned to DRAW_BUFFERi. It could be COLOR_ATTACHMENT0, FRONT, BACK,
 273     * etc.
 274     */
 275    if (drawbuffer < 0 || drawbuffer >= (GLint)ctx->Const.MaxDrawBuffers) {
 276       return INVALID_MASK;
 277    }
 278
 279    switch (ctx->DrawBuffer->ColorDrawBuffer[drawbuffer]) {
 280    case GL_FRONT:
 281       if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 282          mask |= BUFFER_BIT_FRONT_LEFT;
 283       if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
 284          mask |= BUFFER_BIT_FRONT_RIGHT;
 285       break;
 286    case GL_BACK:
 287       /* For GLES contexts with a single buffered configuration, we actually
 288        * only have a front renderbuffer, so any clear calls to GL_BACK should
 289        * affect that buffer. See draw_buffer_enum_to_bitmask for details.
 290        */
 291       if (_mesa_is_gles(ctx))
 292          if (!ctx->DrawBuffer->Visual.doubleBufferMode)
 293             if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 294                mask |= BUFFER_BIT_FRONT_LEFT;
 295       if (att[BUFFER_BACK_LEFT].Renderbuffer)
 296          mask |= BUFFER_BIT_BACK_LEFT;
 297       if (att[BUFFER_BACK_RIGHT].Renderbuffer)
 298          mask |= BUFFER_BIT_BACK_RIGHT;
 299       break;
 300    case GL_LEFT:
 301       if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 302          mask |= BUFFER_BIT_FRONT_LEFT;
 303       if (att[BUFFER_BACK_LEFT].Renderbuffer)
 304          mask |= BUFFER_BIT_BACK_LEFT;
 305       break;
 306    case GL_RIGHT:
 307       if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
 308          mask |= BUFFER_BIT_FRONT_RIGHT;
 309       if (att[BUFFER_BACK_RIGHT].Renderbuffer)
 310          mask |= BUFFER_BIT_BACK_RIGHT;
 311       break;
 312    case GL_FRONT_AND_BACK:
 313       if (att[BUFFER_FRONT_LEFT].Renderbuffer)
 314          mask |= BUFFER_BIT_FRONT_LEFT;
 315       if (att[BUFFER_BACK_LEFT].Renderbuffer)
 316          mask |= BUFFER_BIT_BACK_LEFT;
 317       if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
 318          mask |= BUFFER_BIT_FRONT_RIGHT;
 319       if (att[BUFFER_BACK_RIGHT].Renderbuffer)
 320          mask |= BUFFER_BIT_BACK_RIGHT;
 321       break;
 322    default:
 323       {
 324          GLint buf = ctx->DrawBuffer->_ColorDrawBufferIndexes[drawbuffer];
 325
 326          if (buf >= 0 && att[buf].Renderbuffer) {
 327             mask |= 1 << buf;
 328          }
 329       }
 330    }
 331
 332    return mask;
 333 }
 334
 335
 336
 337 /**
 338  * New in GL 3.0
 339  * Clear signed integer color buffer or stencil buffer (not depth).
 340  */
 341 static ALWAYS_INLINE void
 342 clear_bufferiv(struct gl_context *ctx, GLenum buffer, GLint drawbuffer,
 343                const GLint *value, bool no_error)
 344 {
 345    FLUSH_VERTICES(ctx, 0);
 346    FLUSH_CURRENT(ctx, 0);
 347
 348    if (ctx->NewState) {
 349       _mesa_update_state( ctx );
 350    }
 351
 352    switch (buffer) {
 353    case GL_STENCIL:
 354       /* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
 355        *
 356        *     "ClearBuffer generates an INVALID VALUE error if buffer is
 357        *     COLOR and drawbuffer is less than zero, or greater than the
 358        *     value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
 359        *     STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
 360        */
 361       if (!no_error && drawbuffer != 0) {
 362          _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferiv(drawbuffer=%d)",
 363                      drawbuffer);
 364          return;
 365       }
 366       else if (ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer
 367                && !ctx->RasterDiscard) {
 368          /* Save current stencil clear value, set to 'value', do the
 369           * stencil clear and restore the clear value.
 370           * XXX in the future we may have a new ctx->Driver.ClearBuffer()
 371           * hook instead.
 372           */
 373          const GLuint clearSave = ctx->Stencil.Clear;
 374          ctx->Stencil.Clear = *value;
 375          ctx->Driver.Clear(ctx, BUFFER_BIT_STENCIL);
 376          ctx->Stencil.Clear = clearSave;
 377       }
 378       break;
 379    case GL_COLOR:
 380       {
 381          const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
 382          if (!no_error && mask == INVALID_MASK) {
 383             _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferiv(drawbuffer=%d)",
 384                         drawbuffer);
 385             return;
 386          }
 387          else if (mask && !ctx->RasterDiscard) {
 388             union gl_color_union clearSave;
 389
 390             /* save color */
 391             clearSave = ctx->Color.ClearColor;
 392             /* set color */
 393             COPY_4V(ctx->Color.ClearColor.i, value);
 394             /* clear buffer(s) */
 395             ctx->Driver.Clear(ctx, mask);
 396             /* restore color */
 397             ctx->Color.ClearColor = clearSave;
 398          }
 399       }
 400       break;
 401    default:
 402       if (!no_error) {
 403          /* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
 404           * of the OpenGL 4.5 spec states:
 405           *
 406           *    "An INVALID_ENUM error is generated by ClearBufferiv and
 407           *     ClearNamedFramebufferiv if buffer is not COLOR or STENCIL."
 408           */
 409          _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferiv(buffer=%s)",
 410                      _mesa_enum_to_string(buffer));
 411       }
 412       return;
 413    }
 414 }
 415
 416
 417 void GLAPIENTRY
 418 _mesa_ClearBufferiv_no_error(GLenum buffer, GLint drawbuffer, const GLint *value)
 419 {
 420    GET_CURRENT_CONTEXT(ctx);
 421    clear_bufferiv(ctx, buffer, drawbuffer, value, true);
 422 }
 423
 424
 425 void GLAPIENTRY
 426 _mesa_ClearBufferiv(GLenum buffer, GLint drawbuffer, const GLint *value)
 427 {
 428    GET_CURRENT_CONTEXT(ctx);
 429    clear_bufferiv(ctx, buffer, drawbuffer, value, false);
 430 }
 431
 432
 433 /**
 434  * The ClearBuffer framework is so complicated and so riddled with the
 435  * assumption that the framebuffer is bound that, for now, we will just fake
 436  * direct state access clearing for the user.
 437  */
 438 void GLAPIENTRY
 439 _mesa_ClearNamedFramebufferiv(GLuint framebuffer, GLenum buffer,
 440                               GLint drawbuffer, const GLint *value)
 441 {
 442    GLint oldfb;
 443
 444    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 445    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 446    _mesa_ClearBufferiv(buffer, drawbuffer, value);
 447    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 448 }
 449
 450
 451 /**
 452  * New in GL 3.0
 453  * Clear unsigned integer color buffer (not depth, not stencil).
 454  */
 455 static ALWAYS_INLINE void
 456 clear_bufferuiv(struct gl_context *ctx, GLenum buffer, GLint drawbuffer,
 457                 const GLuint *value, bool no_error)
 458 {
 459    FLUSH_VERTICES(ctx, 0);
 460    FLUSH_CURRENT(ctx, 0);
 461
 462    if (ctx->NewState) {
 463       _mesa_update_state( ctx );
 464    }
 465
 466    switch (buffer) {
 467    case GL_COLOR:
 468       {
 469          const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
 470          if (!no_error && mask == INVALID_MASK) {
 471             _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferuiv(drawbuffer=%d)",
 472                         drawbuffer);
 473             return;
 474          }
 475          else if (mask && !ctx->RasterDiscard) {
 476             union gl_color_union clearSave;
 477
 478             /* save color */
 479             clearSave = ctx->Color.ClearColor;
 480             /* set color */
 481             COPY_4V(ctx->Color.ClearColor.ui, value);
 482             /* clear buffer(s) */
 483             ctx->Driver.Clear(ctx, mask);
 484             /* restore color */
 485             ctx->Color.ClearColor = clearSave;
 486          }
 487       }
 488       break;
 489    default:
 490       if (!no_error) {
 491          /* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
 492           * of the OpenGL 4.5 spec states:
 493           *
 494           *    "An INVALID_ENUM error is generated by ClearBufferuiv and
 495           *     ClearNamedFramebufferuiv if buffer is not COLOR."
 496           */
 497          _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferuiv(buffer=%s)",
 498                      _mesa_enum_to_string(buffer));
 499       }
 500       return;
 501    }
 502 }
 503
 504
 505 void GLAPIENTRY
 506 _mesa_ClearBufferuiv_no_error(GLenum buffer, GLint drawbuffer,
 507                               const GLuint *value)
 508 {
 509    GET_CURRENT_CONTEXT(ctx);
 510    clear_bufferuiv(ctx, buffer, drawbuffer, value, true);
 511 }
 512
 513
 514 void GLAPIENTRY
 515 _mesa_ClearBufferuiv(GLenum buffer, GLint drawbuffer, const GLuint *value)
 516 {
 517    GET_CURRENT_CONTEXT(ctx);
 518    clear_bufferuiv(ctx, buffer, drawbuffer, value, false);
 519 }
 520
 521
 522 /**
 523  * The ClearBuffer framework is so complicated and so riddled with the
 524  * assumption that the framebuffer is bound that, for now, we will just fake
 525  * direct state access clearing for the user.
 526  */
 527 void GLAPIENTRY
 528 _mesa_ClearNamedFramebufferuiv(GLuint framebuffer, GLenum buffer,
 529                                GLint drawbuffer, const GLuint *value)
 530 {
 531    GLint oldfb;
 532
 533    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 534    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 535    _mesa_ClearBufferuiv(buffer, drawbuffer, value);
 536    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 537 }
 538
 539
 540 /**
 541  * New in GL 3.0
 542  * Clear fixed-pt or float color buffer or depth buffer (not stencil).
 543  */
 544 static ALWAYS_INLINE void
 545 clear_bufferfv(struct gl_context *ctx, GLenum buffer, GLint drawbuffer,
 546                const GLfloat *value, bool no_error)
 547 {
 548    FLUSH_VERTICES(ctx, 0);
 549    FLUSH_CURRENT(ctx, 0);
 550
 551    if (ctx->NewState) {
 552       _mesa_update_state( ctx );
 553    }
 554
 555    switch (buffer) {
 556    case GL_DEPTH:
 557       /* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
 558        *
 559        *     "ClearBuffer generates an INVALID VALUE error if buffer is
 560        *     COLOR and drawbuffer is less than zero, or greater than the
 561        *     value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
 562        *     STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
 563        */
 564       if (!no_error && drawbuffer != 0) {
 565          _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfv(drawbuffer=%d)",
 566                      drawbuffer);
 567          return;
 568       }
 569       else if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer
 570                && !ctx->RasterDiscard) {
 571          /* Save current depth clear value, set to 'value', do the
 572           * depth clear and restore the clear value.
 573           * XXX in the future we may have a new ctx->Driver.ClearBuffer()
 574           * hook instead.
 575           */
 576          const GLclampd clearSave = ctx->Depth.Clear;
 577          ctx->Depth.Clear = *value;
 578          ctx->Driver.Clear(ctx, BUFFER_BIT_DEPTH);
 579          ctx->Depth.Clear = clearSave;
 580       }
 581       /* clear depth buffer to value */
 582       break;
 583    case GL_COLOR:
 584       {
 585          const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
 586          if (!no_error && mask == INVALID_MASK) {
 587             _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfv(drawbuffer=%d)",
 588                         drawbuffer);
 589             return;
 590          }
 591          else if (mask && !ctx->RasterDiscard) {
 592             union gl_color_union clearSave;
 593
 594             /* save color */
 595             clearSave = ctx->Color.ClearColor;
 596             /* set color */
 597             COPY_4V(ctx->Color.ClearColor.f, value);
 598             /* clear buffer(s) */
 599             ctx->Driver.Clear(ctx, mask);
 600             /* restore color */
 601             ctx->Color.ClearColor = clearSave;
 602          }
 603       }
 604       break;
 605    default:
 606       if (!no_error) {
 607          /* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
 608           * of the OpenGL 4.5 spec states:
 609           *
 610           *    "An INVALID_ENUM error is generated by ClearBufferfv and
 611           *     ClearNamedFramebufferfv if buffer is not COLOR or DEPTH."
 612           */
 613          _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferfv(buffer=%s)",
 614                      _mesa_enum_to_string(buffer));
 615       }
 616       return;
 617    }
 618 }
 619
 620
 621 void GLAPIENTRY
 622 _mesa_ClearBufferfv_no_error(GLenum buffer, GLint drawbuffer,
 623                              const GLfloat *value)
 624 {
 625    GET_CURRENT_CONTEXT(ctx);
 626    clear_bufferfv(ctx, buffer, drawbuffer, value, true);
 627 }
 628
 629
 630 void GLAPIENTRY
 631 _mesa_ClearBufferfv(GLenum buffer, GLint drawbuffer, const GLfloat *value)
 632 {
 633    GET_CURRENT_CONTEXT(ctx);
 634    clear_bufferfv(ctx, buffer, drawbuffer, value, false);
 635 }
 636
 637
 638 /**
 639  * The ClearBuffer framework is so complicated and so riddled with the
 640  * assumption that the framebuffer is bound that, for now, we will just fake
 641  * direct state access clearing for the user.
 642  */
 643 void GLAPIENTRY
 644 _mesa_ClearNamedFramebufferfv(GLuint framebuffer, GLenum buffer,
 645                               GLint drawbuffer, const GLfloat *value)
 646 {
 647    GLint oldfb;
 648
 649    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 650    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 651    _mesa_ClearBufferfv(buffer, drawbuffer, value);
 652    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 653 }
 654
 655
 656 /**
 657  * New in GL 3.0
 658  * Clear depth/stencil buffer only.
 659  */
 660 static ALWAYS_INLINE void
 661 clear_bufferfi(struct gl_context *ctx, GLenum buffer, GLint drawbuffer,
 662                GLfloat depth, GLint stencil, bool no_error)
 663 {
 664    GLbitfield mask = 0;
 665
 666    FLUSH_VERTICES(ctx, 0);
 667    FLUSH_CURRENT(ctx, 0);
 668
 669    if (!no_error) {
 670       if (buffer != GL_DEPTH_STENCIL) {
 671          _mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferfi(buffer=%s)",
 672                      _mesa_enum_to_string(buffer));
 673          return;
 674       }
 675
 676       /* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
 677        *
 678        *     "ClearBuffer generates an INVALID VALUE error if buffer is
 679        *     COLOR and drawbuffer is less than zero, or greater than the
 680        *     value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
 681        *     STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
 682        */
 683       if (drawbuffer != 0) {
 684          _mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfi(drawbuffer=%d)",
 685                      drawbuffer);
 686          return;
 687       }
 688    }
 689
 690    if (ctx->RasterDiscard)
 691       return;
 692
 693    if (ctx->NewState) {
 694       _mesa_update_state( ctx );
 695    }
 696
 697    if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer)
 698       mask |= BUFFER_BIT_DEPTH;
 699    if (ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer)
 700       mask |= BUFFER_BIT_STENCIL;
 701
 702    if (mask) {
 703       /* save current clear values */
 704       const GLclampd clearDepthSave = ctx->Depth.Clear;
 705       const GLuint clearStencilSave = ctx->Stencil.Clear;
 706
 707       /* set new clear values */
 708       ctx->Depth.Clear = depth;
 709       ctx->Stencil.Clear = stencil;
 710
 711       /* clear buffers */
 712       ctx->Driver.Clear(ctx, mask);
 713
 714       /* restore */
 715       ctx->Depth.Clear = clearDepthSave;
 716       ctx->Stencil.Clear = clearStencilSave;
 717    }
 718 }
 719
 720
 721 void GLAPIENTRY
 722 _mesa_ClearBufferfi_no_error(GLenum buffer, GLint drawbuffer,
 723                              GLfloat depth, GLint stencil)
 724 {
 725    GET_CURRENT_CONTEXT(ctx);
 726    clear_bufferfi(ctx, buffer, drawbuffer, depth, stencil, true);
 727 }
 728
 729
 730 void GLAPIENTRY
 731 _mesa_ClearBufferfi(GLenum buffer, GLint drawbuffer,
 732                     GLfloat depth, GLint stencil)
 733 {
 734    GET_CURRENT_CONTEXT(ctx);
 735    clear_bufferfi(ctx, buffer, drawbuffer, depth, stencil, false);
 736 }
 737
 738
 739 /**
 740  * The ClearBuffer framework is so complicated and so riddled with the
 741  * assumption that the framebuffer is bound that, for now, we will just fake
 742  * direct state access clearing for the user.
 743  */
 744 void GLAPIENTRY
 745 _mesa_ClearNamedFramebufferfi(GLuint framebuffer, GLenum buffer,
 746                               GLint drawbuffer, GLfloat depth, GLint stencil)
 747 {
 748    GLint oldfb;
 749
 750    _mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
 751    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
 752    _mesa_ClearBufferfi(buffer, drawbuffer, depth, stencil);
 753    _mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
 754 }