framebuffer.c revision cd6b8dd9e82fedc55d033131fbc0f8ee950567c8
1/* 2 * Mesa 3-D graphics library 3 * Version: 7.2 4 * 5 * Copyright (C) 1999-2008 Brian Paul 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 "Software"), 9 * to deal in the Software without restriction, including without limitation 10 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 11 * and/or sell copies of the Software, and to permit persons to whom the 12 * Software is furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included 15 * in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23 */ 24 25 26/** 27 * Functions for allocating/managing framebuffers and renderbuffers. 28 * Also, routines for reading/writing renderbuffer data as ubytes, 29 * ushorts, uints, etc. 30 */ 31 32 33#include "glheader.h" 34#include "imports.h" 35#include "buffers.h" 36#include "context.h" 37#include "depthstencil.h" 38#include "formats.h" 39#include "macros.h" 40#include "mtypes.h" 41#include "fbobject.h" 42#include "framebuffer.h" 43#include "renderbuffer.h" 44#include "texobj.h" 45 46 47 48/** 49 * Compute/set the _DepthMax field for the given framebuffer. 50 * This value depends on the Z buffer resolution. 51 */ 52static void 53compute_depth_max(struct gl_framebuffer *fb) 54{ 55 if (fb->Visual.depthBits == 0) { 56 /* Special case. Even if we don't have a depth buffer we need 57 * good values for DepthMax for Z vertex transformation purposes 58 * and for per-fragment fog computation. 59 */ 60 fb->_DepthMax = (1 << 16) - 1; 61 } 62 else if (fb->Visual.depthBits < 32) { 63 fb->_DepthMax = (1 << fb->Visual.depthBits) - 1; 64 } 65 else { 66 /* Special case since shift values greater than or equal to the 67 * number of bits in the left hand expression's type are undefined. 68 */ 69 fb->_DepthMax = 0xffffffff; 70 } 71 fb->_DepthMaxF = (GLfloat) fb->_DepthMax; 72 73 /* Minimum resolvable depth value, for polygon offset */ 74 fb->_MRD = (GLfloat)1.0 / fb->_DepthMaxF; 75} 76 77 78/** 79 * Create and initialize a gl_framebuffer object. 80 * This is intended for creating _window_system_ framebuffers, not generic 81 * framebuffer objects ala GL_EXT_framebuffer_object. 82 * 83 * \sa _mesa_new_framebuffer 84 */ 85struct gl_framebuffer * 86_mesa_create_framebuffer(const GLvisual *visual) 87{ 88 struct gl_framebuffer *fb = CALLOC_STRUCT(gl_framebuffer); 89 assert(visual); 90 if (fb) { 91 _mesa_initialize_framebuffer(fb, visual); 92 } 93 return fb; 94} 95 96 97/** 98 * Allocate a new gl_framebuffer object. 99 * This is the default function for ctx->Driver.NewFramebuffer(). 100 * This is for allocating user-created framebuffers, not window-system 101 * framebuffers! 102 * \sa _mesa_create_framebuffer 103 */ 104struct gl_framebuffer * 105_mesa_new_framebuffer(GLcontext *ctx, GLuint name) 106{ 107 struct gl_framebuffer *fb; 108 (void) ctx; 109 assert(name != 0); 110 fb = CALLOC_STRUCT(gl_framebuffer); 111 if (fb) { 112 fb->Name = name; 113 fb->RefCount = 1; 114 fb->_NumColorDrawBuffers = 1; 115 fb->ColorDrawBuffer[0] = GL_COLOR_ATTACHMENT0_EXT; 116 fb->_ColorDrawBufferIndexes[0] = BUFFER_COLOR0; 117 fb->ColorReadBuffer = GL_COLOR_ATTACHMENT0_EXT; 118 fb->_ColorReadBufferIndex = BUFFER_COLOR0; 119 fb->Delete = _mesa_destroy_framebuffer; 120 _glthread_INIT_MUTEX(fb->Mutex); 121 } 122 return fb; 123} 124 125 126/** 127 * Initialize a gl_framebuffer object. Typically used to initialize 128 * window system-created framebuffers, not user-created framebuffers. 129 * \sa _mesa_create_framebuffer 130 */ 131void 132_mesa_initialize_framebuffer(struct gl_framebuffer *fb, const GLvisual *visual) 133{ 134 assert(fb); 135 assert(visual); 136 137 _mesa_bzero(fb, sizeof(struct gl_framebuffer)); 138 139 _glthread_INIT_MUTEX(fb->Mutex); 140 141 fb->RefCount = 1; 142 143 /* save the visual */ 144 fb->Visual = *visual; 145 146 /* Init read/draw renderbuffer state */ 147 if (visual->doubleBufferMode) { 148 fb->_NumColorDrawBuffers = 1; 149 fb->ColorDrawBuffer[0] = GL_BACK; 150 fb->_ColorDrawBufferIndexes[0] = BUFFER_BACK_LEFT; 151 fb->ColorReadBuffer = GL_BACK; 152 fb->_ColorReadBufferIndex = BUFFER_BACK_LEFT; 153 } 154 else { 155 fb->_NumColorDrawBuffers = 1; 156 fb->ColorDrawBuffer[0] = GL_FRONT; 157 fb->_ColorDrawBufferIndexes[0] = BUFFER_FRONT_LEFT; 158 fb->ColorReadBuffer = GL_FRONT; 159 fb->_ColorReadBufferIndex = BUFFER_FRONT_LEFT; 160 } 161 162 fb->Delete = _mesa_destroy_framebuffer; 163 fb->_Status = GL_FRAMEBUFFER_COMPLETE_EXT; 164 165 compute_depth_max(fb); 166} 167 168 169/** 170 * Deallocate buffer and everything attached to it. 171 * Typically called via the gl_framebuffer->Delete() method. 172 */ 173void 174_mesa_destroy_framebuffer(struct gl_framebuffer *fb) 175{ 176 if (fb) { 177 _mesa_free_framebuffer_data(fb); 178 _mesa_free(fb); 179 } 180} 181 182 183/** 184 * Free all the data hanging off the given gl_framebuffer, but don't free 185 * the gl_framebuffer object itself. 186 */ 187void 188_mesa_free_framebuffer_data(struct gl_framebuffer *fb) 189{ 190 GLuint i; 191 192 assert(fb); 193 assert(fb->RefCount == 0); 194 195 _glthread_DESTROY_MUTEX(fb->Mutex); 196 197 for (i = 0; i < BUFFER_COUNT; i++) { 198 struct gl_renderbuffer_attachment *att = &fb->Attachment[i]; 199 if (att->Renderbuffer) { 200 _mesa_reference_renderbuffer(&att->Renderbuffer, NULL); 201 } 202 if (att->Texture) { 203 _mesa_reference_texobj(&att->Texture, NULL); 204 } 205 ASSERT(!att->Renderbuffer); 206 ASSERT(!att->Texture); 207 att->Type = GL_NONE; 208 } 209 210 /* unbind _Depth/_StencilBuffer to decr ref counts */ 211 _mesa_reference_renderbuffer(&fb->_DepthBuffer, NULL); 212 _mesa_reference_renderbuffer(&fb->_StencilBuffer, NULL); 213} 214 215 216/** 217 * Set *ptr to point to fb, with refcounting and locking. 218 */ 219void 220_mesa_reference_framebuffer(struct gl_framebuffer **ptr, 221 struct gl_framebuffer *fb) 222{ 223 assert(ptr); 224 if (*ptr == fb) { 225 /* no change */ 226 return; 227 } 228 229 if (*ptr) { 230 /* unreference old renderbuffer */ 231 GLboolean deleteFlag = GL_FALSE; 232 struct gl_framebuffer *oldFb = *ptr; 233 234 _glthread_LOCK_MUTEX(oldFb->Mutex); 235 ASSERT(oldFb->RefCount > 0); 236 oldFb->RefCount--; 237 deleteFlag = (oldFb->RefCount == 0); 238 _glthread_UNLOCK_MUTEX(oldFb->Mutex); 239 240 if (deleteFlag) 241 oldFb->Delete(oldFb); 242 243 *ptr = NULL; 244 } 245 assert(!*ptr); 246 247 if (fb) { 248 _glthread_LOCK_MUTEX(fb->Mutex); 249 fb->RefCount++; 250 _glthread_UNLOCK_MUTEX(fb->Mutex); 251 *ptr = fb; 252 } 253} 254 255 256/** 257 * Resize the given framebuffer's renderbuffers to the new width and height. 258 * This should only be used for window-system framebuffers, not 259 * user-created renderbuffers (i.e. made with GL_EXT_framebuffer_object). 260 * This will typically be called via ctx->Driver.ResizeBuffers() or directly 261 * from a device driver. 262 * 263 * \note it's possible for ctx to be null since a window can be resized 264 * without a currently bound rendering context. 265 */ 266void 267_mesa_resize_framebuffer(GLcontext *ctx, struct gl_framebuffer *fb, 268 GLuint width, GLuint height) 269{ 270 GLuint i; 271 272 /* XXX I think we could check if the size is not changing 273 * and return early. 274 */ 275 276 /* For window system framebuffers, Name is zero */ 277 assert(fb->Name == 0); 278 279 for (i = 0; i < BUFFER_COUNT; i++) { 280 struct gl_renderbuffer_attachment *att = &fb->Attachment[i]; 281 if (att->Type == GL_RENDERBUFFER_EXT && att->Renderbuffer) { 282 struct gl_renderbuffer *rb = att->Renderbuffer; 283 /* only resize if size is changing */ 284 if (rb->Width != width || rb->Height != height) { 285 if (rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) { 286 ASSERT(rb->Width == width); 287 ASSERT(rb->Height == height); 288 } 289 else { 290 _mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer"); 291 /* no return */ 292 } 293 } 294 } 295 } 296 297 if (fb->_DepthBuffer) { 298 struct gl_renderbuffer *rb = fb->_DepthBuffer; 299 if (rb->Width != width || rb->Height != height) { 300 if (!rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) { 301 _mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer"); 302 } 303 } 304 } 305 306 if (fb->_StencilBuffer) { 307 struct gl_renderbuffer *rb = fb->_StencilBuffer; 308 if (rb->Width != width || rb->Height != height) { 309 if (!rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) { 310 _mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer"); 311 } 312 } 313 } 314 315 fb->Width = width; 316 fb->Height = height; 317 318 if (ctx) { 319 /* update scissor / window bounds */ 320 _mesa_update_draw_buffer_bounds(ctx); 321 /* Signal new buffer state so that swrast will update its clipping 322 * info (the CLIP_BIT flag). 323 */ 324 ctx->NewState |= _NEW_BUFFERS; 325 } 326} 327 328 329 330/** 331 * XXX THIS IS OBSOLETE - drivers should take care of detecting window 332 * size changes and act accordingly, likely calling _mesa_resize_framebuffer(). 333 * 334 * GL_MESA_resize_buffers extension. 335 * 336 * When this function is called, we'll ask the window system how large 337 * the current window is. If it's a new size, we'll call the driver's 338 * ResizeBuffers function. The driver will then resize its color buffers 339 * as needed, and maybe call the swrast's routine for reallocating 340 * swrast-managed depth/stencil/accum/etc buffers. 341 * \note This function should only be called through the GL API, not 342 * from device drivers (as was done in the past). 343 */ 344void 345_mesa_resizebuffers( GLcontext *ctx ) 346{ 347 ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx ); 348 349 if (MESA_VERBOSE & VERBOSE_API) 350 _mesa_debug(ctx, "glResizeBuffersMESA\n"); 351 352 if (!ctx->Driver.GetBufferSize) { 353 return; 354 } 355 356 if (ctx->WinSysDrawBuffer) { 357 GLuint newWidth, newHeight; 358 GLframebuffer *buffer = ctx->WinSysDrawBuffer; 359 360 assert(buffer->Name == 0); 361 362 /* ask device driver for size of output buffer */ 363 ctx->Driver.GetBufferSize( buffer, &newWidth, &newHeight ); 364 365 /* see if size of device driver's color buffer (window) has changed */ 366 if (buffer->Width != newWidth || buffer->Height != newHeight) { 367 if (ctx->Driver.ResizeBuffers) 368 ctx->Driver.ResizeBuffers(ctx, buffer, newWidth, newHeight ); 369 } 370 } 371 372 if (ctx->WinSysReadBuffer 373 && ctx->WinSysReadBuffer != ctx->WinSysDrawBuffer) { 374 GLuint newWidth, newHeight; 375 GLframebuffer *buffer = ctx->WinSysReadBuffer; 376 377 assert(buffer->Name == 0); 378 379 /* ask device driver for size of read buffer */ 380 ctx->Driver.GetBufferSize( buffer, &newWidth, &newHeight ); 381 382 /* see if size of device driver's color buffer (window) has changed */ 383 if (buffer->Width != newWidth || buffer->Height != newHeight) { 384 if (ctx->Driver.ResizeBuffers) 385 ctx->Driver.ResizeBuffers(ctx, buffer, newWidth, newHeight ); 386 } 387 } 388 389 ctx->NewState |= _NEW_BUFFERS; /* to update scissor / window bounds */ 390} 391 392 393/* 394 * XXX THIS IS OBSOLETE 395 */ 396void GLAPIENTRY 397_mesa_ResizeBuffersMESA( void ) 398{ 399 GET_CURRENT_CONTEXT(ctx); 400 401 if (ctx->Extensions.MESA_resize_buffers) 402 _mesa_resizebuffers( ctx ); 403} 404 405 406 407/** 408 * Examine all the framebuffer's renderbuffers to update the Width/Height 409 * fields of the framebuffer. If we have renderbuffers with different 410 * sizes, set the framebuffer's width and height to the min size. 411 * Note: this is only intended for user-created framebuffers, not 412 * window-system framebuffes. 413 */ 414static void 415update_framebuffer_size(GLcontext *ctx, struct gl_framebuffer *fb) 416{ 417 GLuint minWidth = ~0, minHeight = ~0; 418 GLuint i; 419 420 /* user-created framebuffers only */ 421 assert(fb->Name); 422 423 for (i = 0; i < BUFFER_COUNT; i++) { 424 struct gl_renderbuffer_attachment *att = &fb->Attachment[i]; 425 const struct gl_renderbuffer *rb = att->Renderbuffer; 426 if (rb) { 427 minWidth = MIN2(minWidth, rb->Width); 428 minHeight = MIN2(minHeight, rb->Height); 429 } 430 } 431 432 if (minWidth != ~0) { 433 fb->Width = minWidth; 434 fb->Height = minHeight; 435 } 436 else { 437 fb->Width = 0; 438 fb->Height = 0; 439 } 440} 441 442 443/** 444 * Update the context's current drawing buffer's Xmin, Xmax, Ymin, Ymax fields. 445 * These values are computed from the buffer's width and height and 446 * the scissor box, if it's enabled. 447 * \param ctx the GL context. 448 */ 449void 450_mesa_update_draw_buffer_bounds(GLcontext *ctx) 451{ 452 struct gl_framebuffer *buffer = ctx->DrawBuffer; 453 454 if (!buffer) 455 return; 456 457 if (buffer->Name) { 458 /* user-created framebuffer size depends on the renderbuffers */ 459 update_framebuffer_size(ctx, buffer); 460 } 461 462 buffer->_Xmin = 0; 463 buffer->_Ymin = 0; 464 buffer->_Xmax = buffer->Width; 465 buffer->_Ymax = buffer->Height; 466 467 if (ctx->Scissor.Enabled) { 468 if (ctx->Scissor.X > buffer->_Xmin) { 469 buffer->_Xmin = ctx->Scissor.X; 470 } 471 if (ctx->Scissor.Y > buffer->_Ymin) { 472 buffer->_Ymin = ctx->Scissor.Y; 473 } 474 if (ctx->Scissor.X + ctx->Scissor.Width < buffer->_Xmax) { 475 buffer->_Xmax = ctx->Scissor.X + ctx->Scissor.Width; 476 } 477 if (ctx->Scissor.Y + ctx->Scissor.Height < buffer->_Ymax) { 478 buffer->_Ymax = ctx->Scissor.Y + ctx->Scissor.Height; 479 } 480 /* finally, check for empty region */ 481 if (buffer->_Xmin > buffer->_Xmax) { 482 buffer->_Xmin = buffer->_Xmax; 483 } 484 if (buffer->_Ymin > buffer->_Ymax) { 485 buffer->_Ymin = buffer->_Ymax; 486 } 487 } 488 489 ASSERT(buffer->_Xmin <= buffer->_Xmax); 490 ASSERT(buffer->_Ymin <= buffer->_Ymax); 491} 492 493 494/** 495 * The glGet queries of the framebuffer red/green/blue size, stencil size, 496 * etc. are satisfied by the fields of ctx->DrawBuffer->Visual. These can 497 * change depending on the renderbuffer bindings. This function updates 498 * the given framebuffer's Visual from the current renderbuffer bindings. 499 * 500 * This may apply to user-created framebuffers or window system framebuffers. 501 * 502 * Also note: ctx->DrawBuffer->Visual.depthBits might not equal 503 * ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer.DepthBits. 504 * The former one is used to convert floating point depth values into 505 * integer Z values. 506 */ 507void 508_mesa_update_framebuffer_visual(struct gl_framebuffer *fb) 509{ 510 GLuint i; 511 512 _mesa_bzero(&fb->Visual, sizeof(fb->Visual)); 513 fb->Visual.rgbMode = GL_TRUE; /* assume this */ 514 515#if 0 /* this _might_ be needed */ 516 if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) { 517 /* leave visual fields zero'd */ 518 return; 519 } 520#endif 521 522 /* find first RGB or CI renderbuffer */ 523 for (i = 0; i < BUFFER_COUNT; i++) { 524 if (fb->Attachment[i].Renderbuffer) { 525 const struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer; 526 const GLenum baseFormat = _mesa_get_format_base_format(rb->Format); 527 const gl_format fmt = rb->Format; 528 529 if (baseFormat == GL_RGBA || baseFormat == GL_RGB) { 530 fb->Visual.redBits = _mesa_get_format_bits(fmt, GL_RED_BITS); 531 fb->Visual.greenBits = _mesa_get_format_bits(fmt, GL_GREEN_BITS); 532 fb->Visual.blueBits = _mesa_get_format_bits(fmt, GL_BLUE_BITS); 533 fb->Visual.alphaBits = _mesa_get_format_bits(fmt, GL_ALPHA_BITS); 534 fb->Visual.rgbBits = fb->Visual.redBits 535 + fb->Visual.greenBits + fb->Visual.blueBits; 536 fb->Visual.floatMode = GL_FALSE; 537 fb->Visual.samples = rb->NumSamples; 538 break; 539 } 540 else if (baseFormat == GL_COLOR_INDEX) { 541 fb->Visual.indexBits = _mesa_get_format_bits(fmt, GL_INDEX_BITS); 542 fb->Visual.rgbMode = GL_FALSE; 543 break; 544 } 545 } 546 } 547 548 if (fb->Attachment[BUFFER_DEPTH].Renderbuffer) { 549 const struct gl_renderbuffer *rb = 550 fb->Attachment[BUFFER_DEPTH].Renderbuffer; 551 const gl_format fmt = rb->Format; 552 fb->Visual.haveDepthBuffer = GL_TRUE; 553 fb->Visual.depthBits = _mesa_get_format_bits(fmt, GL_DEPTH_BITS); 554 } 555 556 if (fb->Attachment[BUFFER_STENCIL].Renderbuffer) { 557 const struct gl_renderbuffer *rb = 558 fb->Attachment[BUFFER_STENCIL].Renderbuffer; 559 const gl_format fmt = rb->Format; 560 fb->Visual.haveStencilBuffer = GL_TRUE; 561 fb->Visual.stencilBits = _mesa_get_format_bits(fmt, GL_STENCIL_BITS); 562 } 563 564 if (fb->Attachment[BUFFER_ACCUM].Renderbuffer) { 565 const struct gl_renderbuffer *rb = 566 fb->Attachment[BUFFER_ACCUM].Renderbuffer; 567 const gl_format fmt = rb->Format; 568 fb->Visual.haveAccumBuffer = GL_TRUE; 569 fb->Visual.accumRedBits = _mesa_get_format_bits(fmt, GL_RED_BITS); 570 fb->Visual.accumGreenBits = _mesa_get_format_bits(fmt, GL_GREEN_BITS); 571 fb->Visual.accumBlueBits = _mesa_get_format_bits(fmt, GL_BLUE_BITS); 572 fb->Visual.accumAlphaBits = _mesa_get_format_bits(fmt, GL_ALPHA_BITS); 573 } 574 575 compute_depth_max(fb); 576} 577 578 579/** 580 * Update the framebuffer's _DepthBuffer field using the renderbuffer 581 * found at the given attachment index. 582 * 583 * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer, 584 * create and install a depth wrapper/adaptor. 585 * 586 * \param fb the framebuffer whose _DepthBuffer field to update 587 * \param attIndex indicates the renderbuffer to possibly wrap 588 */ 589void 590_mesa_update_depth_buffer(GLcontext *ctx, 591 struct gl_framebuffer *fb, 592 GLuint attIndex) 593{ 594 struct gl_renderbuffer *depthRb; 595 596 /* only one possiblity for now */ 597 ASSERT(attIndex == BUFFER_DEPTH); 598 599 depthRb = fb->Attachment[attIndex].Renderbuffer; 600 601 if (depthRb && depthRb->_BaseFormat == GL_DEPTH_STENCIL) { 602 /* The attached depth buffer is a GL_DEPTH_STENCIL renderbuffer */ 603 if (!fb->_DepthBuffer 604 || fb->_DepthBuffer->Wrapped != depthRb 605 || _mesa_get_format_base_format(fb->_DepthBuffer->Format) != GL_DEPTH_COMPONENT) { 606 /* need to update wrapper */ 607 struct gl_renderbuffer *wrapper 608 = _mesa_new_z24_renderbuffer_wrapper(ctx, depthRb); 609 _mesa_reference_renderbuffer(&fb->_DepthBuffer, wrapper); 610 ASSERT(fb->_DepthBuffer->Wrapped == depthRb); 611 } 612 } 613 else { 614 /* depthRb may be null */ 615 _mesa_reference_renderbuffer(&fb->_DepthBuffer, depthRb); 616 } 617} 618 619 620/** 621 * Update the framebuffer's _StencilBuffer field using the renderbuffer 622 * found at the given attachment index. 623 * 624 * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer, 625 * create and install a stencil wrapper/adaptor. 626 * 627 * \param fb the framebuffer whose _StencilBuffer field to update 628 * \param attIndex indicates the renderbuffer to possibly wrap 629 */ 630void 631_mesa_update_stencil_buffer(GLcontext *ctx, 632 struct gl_framebuffer *fb, 633 GLuint attIndex) 634{ 635 struct gl_renderbuffer *stencilRb; 636 637 ASSERT(attIndex == BUFFER_DEPTH || 638 attIndex == BUFFER_STENCIL); 639 640 stencilRb = fb->Attachment[attIndex].Renderbuffer; 641 642 if (stencilRb && stencilRb->_BaseFormat == GL_DEPTH_STENCIL) { 643 /* The attached stencil buffer is a GL_DEPTH_STENCIL renderbuffer */ 644 if (!fb->_StencilBuffer 645 || fb->_StencilBuffer->Wrapped != stencilRb 646 || _mesa_get_format_base_format(fb->_StencilBuffer->Format) != GL_STENCIL_INDEX) { 647 /* need to update wrapper */ 648 struct gl_renderbuffer *wrapper 649 = _mesa_new_s8_renderbuffer_wrapper(ctx, stencilRb); 650 _mesa_reference_renderbuffer(&fb->_StencilBuffer, wrapper); 651 ASSERT(fb->_StencilBuffer->Wrapped == stencilRb); 652 } 653 } 654 else { 655 /* stencilRb may be null */ 656 _mesa_reference_renderbuffer(&fb->_StencilBuffer, stencilRb); 657 } 658} 659 660 661/* 662 * Example DrawBuffers scenarios: 663 * 664 * 1. glDrawBuffer(GL_FRONT_AND_BACK), fixed-func or shader writes to 665 * "gl_FragColor" or program writes to the "result.color" register: 666 * 667 * fragment color output renderbuffer 668 * --------------------- --------------- 669 * color[0] Front, Back 670 * 671 * 672 * 2. glDrawBuffers(3, [GL_FRONT, GL_AUX0, GL_AUX1]), shader writes to 673 * gl_FragData[i] or program writes to result.color[i] registers: 674 * 675 * fragment color output renderbuffer 676 * --------------------- --------------- 677 * color[0] Front 678 * color[1] Aux0 679 * color[3] Aux1 680 * 681 * 682 * 3. glDrawBuffers(3, [GL_FRONT, GL_AUX0, GL_AUX1]) and shader writes to 683 * gl_FragColor, or fixed function: 684 * 685 * fragment color output renderbuffer 686 * --------------------- --------------- 687 * color[0] Front, Aux0, Aux1 688 * 689 * 690 * In either case, the list of renderbuffers is stored in the 691 * framebuffer->_ColorDrawBuffers[] array and 692 * framebuffer->_NumColorDrawBuffers indicates the number of buffers. 693 * The renderer (like swrast) has to look at the current fragment shader 694 * to see if it writes to gl_FragColor vs. gl_FragData[i] to determine 695 * how to map color outputs to renderbuffers. 696 * 697 * Note that these two calls are equivalent (for fixed function fragment 698 * shading anyway): 699 * a) glDrawBuffer(GL_FRONT_AND_BACK); (assuming non-stereo framebuffer) 700 * b) glDrawBuffers(2, [GL_FRONT_LEFT, GL_BACK_LEFT]); 701 */ 702 703 704 705 706/** 707 * Update the (derived) list of color drawing renderbuffer pointers. 708 * Later, when we're rendering we'll loop from 0 to _NumColorDrawBuffers 709 * writing colors. 710 */ 711static void 712update_color_draw_buffers(GLcontext *ctx, struct gl_framebuffer *fb) 713{ 714 GLuint output; 715 716 /* set 0th buffer to NULL now in case _NumColorDrawBuffers is zero */ 717 fb->_ColorDrawBuffers[0] = NULL; 718 719 for (output = 0; output < fb->_NumColorDrawBuffers; output++) { 720 GLint buf = fb->_ColorDrawBufferIndexes[output]; 721 if (buf >= 0) { 722 fb->_ColorDrawBuffers[output] = fb->Attachment[buf].Renderbuffer; 723 } 724 else { 725 fb->_ColorDrawBuffers[output] = NULL; 726 } 727 } 728} 729 730 731/** 732 * Update the (derived) color read renderbuffer pointer. 733 * Unlike the DrawBuffer, we can only read from one (or zero) color buffers. 734 */ 735static void 736update_color_read_buffer(GLcontext *ctx, struct gl_framebuffer *fb) 737{ 738 (void) ctx; 739 if (fb->_ColorReadBufferIndex == -1 || 740 fb->DeletePending || 741 fb->Width == 0 || 742 fb->Height == 0) { 743 fb->_ColorReadBuffer = NULL; /* legal! */ 744 } 745 else { 746 ASSERT(fb->_ColorReadBufferIndex >= 0); 747 ASSERT(fb->_ColorReadBufferIndex < BUFFER_COUNT); 748 fb->_ColorReadBuffer 749 = fb->Attachment[fb->_ColorReadBufferIndex].Renderbuffer; 750 } 751} 752 753 754/** 755 * Update a gl_framebuffer's derived state. 756 * 757 * Specifically, update these framebuffer fields: 758 * _ColorDrawBuffers 759 * _NumColorDrawBuffers 760 * _ColorReadBuffer 761 * _DepthBuffer 762 * _StencilBuffer 763 * 764 * If the framebuffer is user-created, make sure it's complete. 765 * 766 * The following functions (at least) can effect framebuffer state: 767 * glReadBuffer, glDrawBuffer, glDrawBuffersARB, glFramebufferRenderbufferEXT, 768 * glRenderbufferStorageEXT. 769 */ 770static void 771update_framebuffer(GLcontext *ctx, struct gl_framebuffer *fb) 772{ 773 if (fb->Name == 0) { 774 /* This is a window-system framebuffer */ 775 /* Need to update the FB's GL_DRAW_BUFFER state to match the 776 * context state (GL_READ_BUFFER too). 777 */ 778 if (fb->ColorDrawBuffer[0] != ctx->Color.DrawBuffer[0]) { 779 _mesa_drawbuffers(ctx, ctx->Const.MaxDrawBuffers, 780 ctx->Color.DrawBuffer, NULL); 781 } 782 if (fb->ColorReadBuffer != ctx->Pixel.ReadBuffer) { 783 784 } 785 } 786 else { 787 /* This is a user-created framebuffer. 788 * Completeness only matters for user-created framebuffers. 789 */ 790 if (fb->_Status != GL_FRAMEBUFFER_COMPLETE) { 791 _mesa_test_framebuffer_completeness(ctx, fb); 792 } 793 } 794 795 /* Strictly speaking, we don't need to update the draw-state 796 * if this FB is bound as ctx->ReadBuffer (and conversely, the 797 * read-state if this FB is bound as ctx->DrawBuffer), but no 798 * harm. 799 */ 800 update_color_draw_buffers(ctx, fb); 801 update_color_read_buffer(ctx, fb); 802 _mesa_update_depth_buffer(ctx, fb, BUFFER_DEPTH); 803 _mesa_update_stencil_buffer(ctx, fb, BUFFER_STENCIL); 804 805 compute_depth_max(fb); 806} 807 808 809/** 810 * Update state related to the current draw/read framebuffers. 811 */ 812void 813_mesa_update_framebuffer(GLcontext *ctx) 814{ 815 struct gl_framebuffer *drawFb = ctx->DrawBuffer; 816 struct gl_framebuffer *readFb = ctx->ReadBuffer; 817 818 update_framebuffer(ctx, drawFb); 819 if (readFb != drawFb) 820 update_framebuffer(ctx, readFb); 821} 822 823 824/** 825 * Check if the renderbuffer for a read operation (glReadPixels, glCopyPixels, 826 * glCopyTex[Sub]Image, etc) exists. 827 * \param format a basic image format such as GL_RGB, GL_RGBA, GL_ALPHA, 828 * GL_DEPTH_COMPONENT, etc. or GL_COLOR, GL_DEPTH, GL_STENCIL. 829 * \return GL_TRUE if buffer exists, GL_FALSE otherwise 830 */ 831GLboolean 832_mesa_source_buffer_exists(GLcontext *ctx, GLenum format) 833{ 834 const struct gl_renderbuffer_attachment *att = ctx->ReadBuffer->Attachment; 835 836 /* If we don't know the framebuffer status, update it now */ 837 if (ctx->ReadBuffer->_Status == 0) { 838 _mesa_test_framebuffer_completeness(ctx, ctx->ReadBuffer); 839 } 840 841 if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) { 842 return GL_FALSE; 843 } 844 845 switch (format) { 846 case GL_COLOR: 847 case GL_RED: 848 case GL_GREEN: 849 case GL_BLUE: 850 case GL_ALPHA: 851 case GL_LUMINANCE: 852 case GL_LUMINANCE_ALPHA: 853 case GL_INTENSITY: 854 case GL_RGB: 855 case GL_BGR: 856 case GL_RGBA: 857 case GL_BGRA: 858 case GL_ABGR_EXT: 859 case GL_COLOR_INDEX: 860 if (ctx->ReadBuffer->_ColorReadBuffer == NULL) { 861 return GL_FALSE; 862 } 863 ASSERT(_mesa_get_format_bits(ctx->ReadBuffer->_ColorReadBuffer->Format, GL_RED_BITS) > 0 || 864 _mesa_get_format_bits(ctx->ReadBuffer->_ColorReadBuffer->Format, GL_INDEX_BITS) > 0); 865 break; 866 case GL_DEPTH: 867 case GL_DEPTH_COMPONENT: 868 if (!att[BUFFER_DEPTH].Renderbuffer) { 869 return GL_FALSE; 870 } 871 /*ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);*/ 872 break; 873 case GL_STENCIL: 874 case GL_STENCIL_INDEX: 875 if (!att[BUFFER_STENCIL].Renderbuffer) { 876 return GL_FALSE; 877 } 878 /*ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);*/ 879 break; 880 case GL_DEPTH_STENCIL_EXT: 881 if (!att[BUFFER_DEPTH].Renderbuffer || 882 !att[BUFFER_STENCIL].Renderbuffer) { 883 return GL_FALSE; 884 } 885 /* 886 ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0); 887 ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0); 888 */ 889 break; 890 default: 891 _mesa_problem(ctx, 892 "Unexpected format 0x%x in _mesa_source_buffer_exists", 893 format); 894 return GL_FALSE; 895 } 896 897 /* OK */ 898 return GL_TRUE; 899} 900 901 902/** 903 * As above, but for drawing operations. 904 * XXX could do some code merging w/ above function. 905 */ 906GLboolean 907_mesa_dest_buffer_exists(GLcontext *ctx, GLenum format) 908{ 909 const struct gl_renderbuffer_attachment *att = ctx->DrawBuffer->Attachment; 910 911 /* If we don't know the framebuffer status, update it now */ 912 if (ctx->DrawBuffer->_Status == 0) { 913 _mesa_test_framebuffer_completeness(ctx, ctx->DrawBuffer); 914 } 915 916 if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) { 917 return GL_FALSE; 918 } 919 920 switch (format) { 921 case GL_COLOR: 922 case GL_RED: 923 case GL_GREEN: 924 case GL_BLUE: 925 case GL_ALPHA: 926 case GL_LUMINANCE: 927 case GL_LUMINANCE_ALPHA: 928 case GL_INTENSITY: 929 case GL_RGB: 930 case GL_BGR: 931 case GL_RGBA: 932 case GL_BGRA: 933 case GL_ABGR_EXT: 934 case GL_COLOR_INDEX: 935 /* Nothing special since GL_DRAW_BUFFER could be GL_NONE. */ 936 /* Could assert that colorbuffer has RedBits > 0 */ 937 break; 938 case GL_DEPTH: 939 case GL_DEPTH_COMPONENT: 940 if (!att[BUFFER_DEPTH].Renderbuffer) { 941 return GL_FALSE; 942 } 943 /*ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);*/ 944 break; 945 case GL_STENCIL: 946 case GL_STENCIL_INDEX: 947 if (!att[BUFFER_STENCIL].Renderbuffer) { 948 return GL_FALSE; 949 } 950 /*ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);*/ 951 break; 952 case GL_DEPTH_STENCIL_EXT: 953 if (!att[BUFFER_DEPTH].Renderbuffer || 954 !att[BUFFER_STENCIL].Renderbuffer) { 955 return GL_FALSE; 956 } 957 /* 958 ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0); 959 ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0); 960 */ 961 break; 962 default: 963 _mesa_problem(ctx, 964 "Unexpected format 0x%x in _mesa_dest_buffer_exists", 965 format); 966 return GL_FALSE; 967 } 968 969 /* OK */ 970 return GL_TRUE; 971} 972 973GLenum 974_mesa_get_color_read_format(GLcontext *ctx) 975{ 976 switch (ctx->ReadBuffer->_ColorReadBuffer->Format) { 977 case MESA_FORMAT_ARGB8888: 978 return GL_BGRA; 979 case MESA_FORMAT_RGB565: 980 return GL_BGR; 981 default: 982 return GL_RGBA; 983 } 984} 985 986GLenum 987_mesa_get_color_read_type(GLcontext *ctx) 988{ 989 switch (ctx->ReadBuffer->_ColorReadBuffer->Format) { 990 case MESA_FORMAT_ARGB8888: 991 return GL_UNSIGNED_BYTE; 992 case MESA_FORMAT_RGB565: 993 return GL_UNSIGNED_SHORT_5_6_5_REV; 994 default: 995 return GL_UNSIGNED_BYTE; 996 } 997} 998