1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008 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 * Functions for allocating/managing framebuffers and renderbuffers.
28 * Also, routines for reading/writing renderbuffer data as ubytes,
29 * ushorts, uints, etc.
30 */
31
32 #include <stdio.h>
33 #include "glheader.h"
34
35 #include "blend.h"
36 #include "buffers.h"
37 #include "context.h"
38 #include "draw_validate.h"
39 #include "enums.h"
40 #include "formats.h"
41 #include "macros.h"
42 #include "mtypes.h"
43 #include "fbobject.h"
44 #include "framebuffer.h"
45 #include "renderbuffer.h"
46 #include "texobj.h"
47 #include "glformats.h"
48 #include "state.h"
49 #include "util/u_memory.h"
50
51
52
53 /**
54 * Compute/set the _DepthMax field for the given framebuffer.
55 * This value depends on the Z buffer resolution.
56 */
57 static void
compute_depth_max(struct gl_framebuffer * fb)58 compute_depth_max(struct gl_framebuffer *fb)
59 {
60 if (fb->Visual.depthBits == 0) {
61 /* Special case. Even if we don't have a depth buffer we need
62 * good values for DepthMax for Z vertex transformation purposes
63 * and for per-fragment fog computation.
64 */
65 fb->_DepthMax = (1 << 16) - 1;
66 }
67 else if (fb->Visual.depthBits < 32) {
68 fb->_DepthMax = (1 << fb->Visual.depthBits) - 1;
69 }
70 else {
71 /* Special case since shift values greater than or equal to the
72 * number of bits in the left hand expression's type are undefined.
73 */
74 fb->_DepthMax = 0xffffffff;
75 }
76 fb->_DepthMaxF = (GLfloat) fb->_DepthMax;
77
78 /* Minimum resolvable depth value, for polygon offset */
79 fb->_MRD = (GLfloat)1.0 / fb->_DepthMaxF;
80 }
81
82 /**
83 * Allocate a new gl_framebuffer object.
84 * This is the default function for ctx->Driver.NewFramebuffer().
85 * This is for allocating user-created framebuffers, not window-system
86 * framebuffers!
87 */
88 struct gl_framebuffer *
_mesa_new_framebuffer(struct gl_context * ctx,GLuint name)89 _mesa_new_framebuffer(struct gl_context *ctx, GLuint name)
90 {
91 struct gl_framebuffer *fb;
92 (void) ctx;
93 assert(name != 0);
94 fb = CALLOC_STRUCT(gl_framebuffer);
95 if (fb) {
96 _mesa_initialize_user_framebuffer(fb, name);
97 }
98 return fb;
99 }
100
101
102 /**
103 * Initialize a gl_framebuffer object. Typically used to initialize
104 * window system-created framebuffers, not user-created framebuffers.
105 * \sa _mesa_initialize_user_framebuffer
106 */
107 void
_mesa_initialize_window_framebuffer(struct gl_framebuffer * fb,const struct gl_config * visual)108 _mesa_initialize_window_framebuffer(struct gl_framebuffer *fb,
109 const struct gl_config *visual)
110 {
111 assert(fb);
112 assert(visual);
113
114 memset(fb, 0, sizeof(struct gl_framebuffer));
115
116 simple_mtx_init(&fb->Mutex, mtx_plain);
117
118 fb->RefCount = 1;
119
120 /* save the visual */
121 fb->Visual = *visual;
122
123 /* Init read/draw renderbuffer state */
124 if (visual->doubleBufferMode) {
125 fb->_NumColorDrawBuffers = 1;
126 fb->ColorDrawBuffer[0] = GL_BACK;
127 fb->_ColorDrawBufferIndexes[0] = BUFFER_BACK_LEFT;
128 fb->ColorReadBuffer = GL_BACK;
129 fb->_ColorReadBufferIndex = BUFFER_BACK_LEFT;
130 }
131 else {
132 fb->_NumColorDrawBuffers = 1;
133 fb->ColorDrawBuffer[0] = GL_FRONT;
134 fb->_ColorDrawBufferIndexes[0] = BUFFER_FRONT_LEFT;
135 fb->ColorReadBuffer = GL_FRONT;
136 fb->_ColorReadBufferIndex = BUFFER_FRONT_LEFT;
137 }
138
139 fb->Delete = _mesa_destroy_framebuffer;
140 fb->_Status = GL_FRAMEBUFFER_COMPLETE_EXT;
141 fb->_AllColorBuffersFixedPoint = !visual->floatMode;
142 fb->_HasSNormOrFloatColorBuffer = visual->floatMode;
143 fb->_HasAttachments = true;
144 fb->FlipY = true;
145
146 fb->SampleLocationTable = NULL;
147 fb->ProgrammableSampleLocations = 0;
148 fb->SampleLocationPixelGrid = 0;
149
150 compute_depth_max(fb);
151 }
152
153
154 /**
155 * Initialize a user-created gl_framebuffer object.
156 * \sa _mesa_initialize_window_framebuffer
157 */
158 void
_mesa_initialize_user_framebuffer(struct gl_framebuffer * fb,GLuint name)159 _mesa_initialize_user_framebuffer(struct gl_framebuffer *fb, GLuint name)
160 {
161 assert(fb);
162 assert(name);
163
164 memset(fb, 0, sizeof(struct gl_framebuffer));
165
166 fb->Name = name;
167 fb->RefCount = 1;
168 fb->_NumColorDrawBuffers = 1;
169 fb->ColorDrawBuffer[0] = GL_COLOR_ATTACHMENT0_EXT;
170 fb->_ColorDrawBufferIndexes[0] = BUFFER_COLOR0;
171 fb->ColorReadBuffer = GL_COLOR_ATTACHMENT0_EXT;
172 fb->_ColorReadBufferIndex = BUFFER_COLOR0;
173 fb->SampleLocationTable = NULL;
174 fb->ProgrammableSampleLocations = 0;
175 fb->SampleLocationPixelGrid = 0;
176 fb->Delete = _mesa_destroy_framebuffer;
177 simple_mtx_init(&fb->Mutex, mtx_plain);
178 }
179
180
181 /**
182 * Deallocate buffer and everything attached to it.
183 * Typically called via the gl_framebuffer->Delete() method.
184 */
185 void
_mesa_destroy_framebuffer(struct gl_framebuffer * fb)186 _mesa_destroy_framebuffer(struct gl_framebuffer *fb)
187 {
188 if (fb) {
189 _mesa_free_framebuffer_data(fb);
190 free(fb->Label);
191 free(fb);
192 }
193 }
194
195
196 /**
197 * Free all the data hanging off the given gl_framebuffer, but don't free
198 * the gl_framebuffer object itself.
199 */
200 void
_mesa_free_framebuffer_data(struct gl_framebuffer * fb)201 _mesa_free_framebuffer_data(struct gl_framebuffer *fb)
202 {
203 assert(fb);
204 assert(fb->RefCount == 0);
205
206 simple_mtx_destroy(&fb->Mutex);
207
208 for (unsigned i = 0; i < BUFFER_COUNT; i++) {
209 struct gl_renderbuffer_attachment *att = &fb->Attachment[i];
210 if (att->Renderbuffer) {
211 _mesa_reference_renderbuffer(&att->Renderbuffer, NULL);
212 }
213 if (att->Texture) {
214 _mesa_reference_texobj(&att->Texture, NULL);
215 }
216 assert(!att->Renderbuffer);
217 assert(!att->Texture);
218 att->Type = GL_NONE;
219 }
220
221 free(fb->SampleLocationTable);
222 fb->SampleLocationTable = NULL;
223 }
224
225
226 /**
227 * Set *ptr to point to fb, with refcounting and locking.
228 * This is normally only called from the _mesa_reference_framebuffer() macro
229 * when there's a real pointer change.
230 */
231 void
_mesa_reference_framebuffer_(struct gl_framebuffer ** ptr,struct gl_framebuffer * fb)232 _mesa_reference_framebuffer_(struct gl_framebuffer **ptr,
233 struct gl_framebuffer *fb)
234 {
235 if (*ptr) {
236 /* unreference old renderbuffer */
237 GLboolean deleteFlag = GL_FALSE;
238 struct gl_framebuffer *oldFb = *ptr;
239
240 simple_mtx_lock(&oldFb->Mutex);
241 assert(oldFb->RefCount > 0);
242 oldFb->RefCount--;
243 deleteFlag = (oldFb->RefCount == 0);
244 simple_mtx_unlock(&oldFb->Mutex);
245
246 if (deleteFlag)
247 oldFb->Delete(oldFb);
248
249 *ptr = NULL;
250 }
251
252 if (fb) {
253 simple_mtx_lock(&fb->Mutex);
254 fb->RefCount++;
255 simple_mtx_unlock(&fb->Mutex);
256 *ptr = fb;
257 }
258 }
259
260
261 /**
262 * Resize the given framebuffer's renderbuffers to the new width and height.
263 * This should only be used for window-system framebuffers, not
264 * user-created renderbuffers (i.e. made with GL_EXT_framebuffer_object).
265 * This will typically be called directly from a device driver.
266 *
267 * \note it's possible for ctx to be null since a window can be resized
268 * without a currently bound rendering context.
269 */
270 void
_mesa_resize_framebuffer(struct gl_context * ctx,struct gl_framebuffer * fb,GLuint width,GLuint height)271 _mesa_resize_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb,
272 GLuint width, GLuint height)
273 {
274 /* XXX I think we could check if the size is not changing
275 * and return early.
276 */
277
278 /* Can only resize win-sys framebuffer objects */
279 assert(_mesa_is_winsys_fbo(fb));
280
281 for (unsigned i = 0; i < BUFFER_COUNT; i++) {
282 struct gl_renderbuffer_attachment *att = &fb->Attachment[i];
283 if (att->Type == GL_RENDERBUFFER_EXT && att->Renderbuffer) {
284 struct gl_renderbuffer *rb = att->Renderbuffer;
285 /* only resize if size is changing */
286 if (rb->Width != width || rb->Height != height) {
287 if (rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) {
288 assert(rb->Width == width);
289 assert(rb->Height == height);
290 }
291 else {
292 _mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer");
293 /* no return */
294 }
295 }
296 }
297 }
298
299 fb->Width = width;
300 fb->Height = height;
301
302 if (ctx) {
303 /* update scissor / window bounds */
304 _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
305 /* Signal new buffer state so that swrast will update its clipping
306 * info (the CLIP_BIT flag).
307 */
308 ctx->NewState |= _NEW_BUFFERS;
309 }
310 }
311
312 /**
313 * Given a bounding box, intersect the bounding box with the scissor of
314 * a specified vieport.
315 *
316 * \param ctx GL context.
317 * \param idx Index of the desired viewport
318 * \param bbox Bounding box for the scissored viewport. Stored as xmin,
319 * xmax, ymin, ymax.
320 */
321 void
_mesa_intersect_scissor_bounding_box(const struct gl_context * ctx,unsigned idx,int * bbox)322 _mesa_intersect_scissor_bounding_box(const struct gl_context *ctx,
323 unsigned idx, int *bbox)
324 {
325 if (ctx->Scissor.EnableFlags & (1u << idx)) {
326 if (ctx->Scissor.ScissorArray[idx].X > bbox[0]) {
327 bbox[0] = ctx->Scissor.ScissorArray[idx].X;
328 }
329 if (ctx->Scissor.ScissorArray[idx].Y > bbox[2]) {
330 bbox[2] = ctx->Scissor.ScissorArray[idx].Y;
331 }
332 if (ctx->Scissor.ScissorArray[idx].X + ctx->Scissor.ScissorArray[idx].Width < bbox[1]) {
333 bbox[1] = ctx->Scissor.ScissorArray[idx].X + ctx->Scissor.ScissorArray[idx].Width;
334 }
335 if (ctx->Scissor.ScissorArray[idx].Y + ctx->Scissor.ScissorArray[idx].Height < bbox[3]) {
336 bbox[3] = ctx->Scissor.ScissorArray[idx].Y + ctx->Scissor.ScissorArray[idx].Height;
337 }
338 /* finally, check for empty region */
339 if (bbox[0] > bbox[1]) {
340 bbox[0] = bbox[1];
341 }
342 if (bbox[2] > bbox[3]) {
343 bbox[2] = bbox[3];
344 }
345 }
346 }
347
348 /**
349 * Calculate the inclusive bounding box for the scissor of a specific viewport
350 *
351 * \param ctx GL context.
352 * \param buffer Framebuffer to be checked against
353 * \param idx Index of the desired viewport
354 * \param bbox Bounding box for the scissored viewport. Stored as xmin,
355 * xmax, ymin, ymax.
356 *
357 * \warning This function assumes that the framebuffer dimensions are up to
358 * date.
359 *
360 * \sa _mesa_clip_to_region
361 */
362 static void
scissor_bounding_box(const struct gl_context * ctx,const struct gl_framebuffer * buffer,unsigned idx,int * bbox)363 scissor_bounding_box(const struct gl_context *ctx,
364 const struct gl_framebuffer *buffer,
365 unsigned idx, int *bbox)
366 {
367 bbox[0] = 0;
368 bbox[2] = 0;
369 bbox[1] = buffer->Width;
370 bbox[3] = buffer->Height;
371
372 _mesa_intersect_scissor_bounding_box(ctx, idx, bbox);
373
374 assert(bbox[0] <= bbox[1]);
375 assert(bbox[2] <= bbox[3]);
376 }
377
378 /**
379 * Update the context's current drawing buffer's Xmin, Xmax, Ymin, Ymax fields.
380 * These values are computed from the buffer's width and height and
381 * the scissor box, if it's enabled.
382 * \param ctx the GL context.
383 */
384 void
_mesa_update_draw_buffer_bounds(struct gl_context * ctx,struct gl_framebuffer * buffer)385 _mesa_update_draw_buffer_bounds(struct gl_context *ctx,
386 struct gl_framebuffer *buffer)
387 {
388 int bbox[4];
389
390 if (!buffer)
391 return;
392
393 /* Default to the first scissor as that's always valid */
394 scissor_bounding_box(ctx, buffer, 0, bbox);
395 buffer->_Xmin = bbox[0];
396 buffer->_Ymin = bbox[2];
397 buffer->_Xmax = bbox[1];
398 buffer->_Ymax = bbox[3];
399 }
400
401
402 /**
403 * The glGet queries of the framebuffer red/green/blue size, stencil size,
404 * etc. are satisfied by the fields of ctx->DrawBuffer->Visual. These can
405 * change depending on the renderbuffer bindings. This function updates
406 * the given framebuffer's Visual from the current renderbuffer bindings.
407 *
408 * This may apply to user-created framebuffers or window system framebuffers.
409 *
410 * Also note: ctx->DrawBuffer->Visual.depthBits might not equal
411 * ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer.DepthBits.
412 * The former one is used to convert floating point depth values into
413 * integer Z values.
414 */
415 void
_mesa_update_framebuffer_visual(struct gl_context * ctx,struct gl_framebuffer * fb)416 _mesa_update_framebuffer_visual(struct gl_context *ctx,
417 struct gl_framebuffer *fb)
418 {
419 memset(&fb->Visual, 0, sizeof(fb->Visual));
420
421 /* find first RGB renderbuffer */
422 for (unsigned i = 0; i < BUFFER_COUNT; i++) {
423 if (fb->Attachment[i].Renderbuffer) {
424 const struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer;
425 const GLenum baseFormat = _mesa_get_format_base_format(rb->Format);
426 const mesa_format fmt = rb->Format;
427
428 /* Grab samples and sampleBuffers from any attachment point (assuming
429 * the framebuffer is complete, we'll get the same answer from all
430 * attachments).
431 */
432 fb->Visual.samples = rb->NumSamples;
433
434 if (_mesa_is_legal_color_format(ctx, baseFormat)) {
435 fb->Visual.redBits = _mesa_get_format_bits(fmt, GL_RED_BITS);
436 fb->Visual.greenBits = _mesa_get_format_bits(fmt, GL_GREEN_BITS);
437 fb->Visual.blueBits = _mesa_get_format_bits(fmt, GL_BLUE_BITS);
438 fb->Visual.alphaBits = _mesa_get_format_bits(fmt, GL_ALPHA_BITS);
439 fb->Visual.rgbBits = fb->Visual.redBits + fb->Visual.greenBits +
440 fb->Visual.blueBits + fb->Visual.alphaBits;
441 if (_mesa_is_format_srgb(fmt))
442 fb->Visual.sRGBCapable = ctx->Extensions.EXT_sRGB;
443 break;
444 }
445 }
446 }
447
448 fb->Visual.floatMode = GL_FALSE;
449 for (unsigned i = 0; i < BUFFER_COUNT; i++) {
450 if (i == BUFFER_DEPTH)
451 continue;
452 if (fb->Attachment[i].Renderbuffer) {
453 const struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer;
454 const mesa_format fmt = rb->Format;
455
456 if (_mesa_get_format_datatype(fmt) == GL_FLOAT) {
457 fb->Visual.floatMode = GL_TRUE;
458 break;
459 }
460 }
461 }
462
463 if (fb->Attachment[BUFFER_DEPTH].Renderbuffer) {
464 const struct gl_renderbuffer *rb =
465 fb->Attachment[BUFFER_DEPTH].Renderbuffer;
466 const mesa_format fmt = rb->Format;
467 fb->Visual.depthBits = _mesa_get_format_bits(fmt, GL_DEPTH_BITS);
468 }
469
470 if (fb->Attachment[BUFFER_STENCIL].Renderbuffer) {
471 const struct gl_renderbuffer *rb =
472 fb->Attachment[BUFFER_STENCIL].Renderbuffer;
473 const mesa_format fmt = rb->Format;
474 fb->Visual.stencilBits = _mesa_get_format_bits(fmt, GL_STENCIL_BITS);
475 }
476
477 if (fb->Attachment[BUFFER_ACCUM].Renderbuffer) {
478 const struct gl_renderbuffer *rb =
479 fb->Attachment[BUFFER_ACCUM].Renderbuffer;
480 const mesa_format fmt = rb->Format;
481 fb->Visual.accumRedBits = _mesa_get_format_bits(fmt, GL_RED_BITS);
482 fb->Visual.accumGreenBits = _mesa_get_format_bits(fmt, GL_GREEN_BITS);
483 fb->Visual.accumBlueBits = _mesa_get_format_bits(fmt, GL_BLUE_BITS);
484 fb->Visual.accumAlphaBits = _mesa_get_format_bits(fmt, GL_ALPHA_BITS);
485 }
486
487 compute_depth_max(fb);
488 _mesa_update_allow_draw_out_of_order(ctx);
489 _mesa_update_valid_to_render_state(ctx);
490 }
491
492
493 /*
494 * Example DrawBuffers scenarios:
495 *
496 * 1. glDrawBuffer(GL_FRONT_AND_BACK), fixed-func or shader writes to
497 * "gl_FragColor" or program writes to the "result.color" register:
498 *
499 * fragment color output renderbuffer
500 * --------------------- ---------------
501 * color[0] Front, Back
502 *
503 *
504 * 2. glDrawBuffers(3, [GL_FRONT, GL_AUX0, GL_AUX1]), shader writes to
505 * gl_FragData[i] or program writes to result.color[i] registers:
506 *
507 * fragment color output renderbuffer
508 * --------------------- ---------------
509 * color[0] Front
510 * color[1] Aux0
511 * color[3] Aux1
512 *
513 *
514 * 3. glDrawBuffers(3, [GL_FRONT, GL_AUX0, GL_AUX1]) and shader writes to
515 * gl_FragColor, or fixed function:
516 *
517 * fragment color output renderbuffer
518 * --------------------- ---------------
519 * color[0] Front, Aux0, Aux1
520 *
521 *
522 * In either case, the list of renderbuffers is stored in the
523 * framebuffer->_ColorDrawBuffers[] array and
524 * framebuffer->_NumColorDrawBuffers indicates the number of buffers.
525 * The renderer (like swrast) has to look at the current fragment shader
526 * to see if it writes to gl_FragColor vs. gl_FragData[i] to determine
527 * how to map color outputs to renderbuffers.
528 *
529 * Note that these two calls are equivalent (for fixed function fragment
530 * shading anyway):
531 * a) glDrawBuffer(GL_FRONT_AND_BACK); (assuming non-stereo framebuffer)
532 * b) glDrawBuffers(2, [GL_FRONT_LEFT, GL_BACK_LEFT]);
533 */
534
535
536
537
538 /**
539 * Update the (derived) list of color drawing renderbuffer pointers.
540 * Later, when we're rendering we'll loop from 0 to _NumColorDrawBuffers
541 * writing colors.
542 */
543 static void
update_color_draw_buffers(struct gl_framebuffer * fb)544 update_color_draw_buffers(struct gl_framebuffer *fb)
545 {
546 GLuint output;
547
548 /* set 0th buffer to NULL now in case _NumColorDrawBuffers is zero */
549 fb->_ColorDrawBuffers[0] = NULL;
550
551 for (output = 0; output < fb->_NumColorDrawBuffers; output++) {
552 gl_buffer_index buf = fb->_ColorDrawBufferIndexes[output];
553 if (buf != BUFFER_NONE) {
554 fb->_ColorDrawBuffers[output] = fb->Attachment[buf].Renderbuffer;
555 }
556 else {
557 fb->_ColorDrawBuffers[output] = NULL;
558 }
559 }
560 }
561
562
563 /**
564 * Update the (derived) color read renderbuffer pointer.
565 * Unlike the DrawBuffer, we can only read from one (or zero) color buffers.
566 */
567 static void
update_color_read_buffer(struct gl_framebuffer * fb)568 update_color_read_buffer(struct gl_framebuffer *fb)
569 {
570 if (fb->_ColorReadBufferIndex == BUFFER_NONE ||
571 fb->DeletePending ||
572 fb->Width == 0 ||
573 fb->Height == 0) {
574 fb->_ColorReadBuffer = NULL; /* legal! */
575 }
576 else {
577 assert(fb->_ColorReadBufferIndex >= 0);
578 assert(fb->_ColorReadBufferIndex < BUFFER_COUNT);
579 fb->_ColorReadBuffer
580 = fb->Attachment[fb->_ColorReadBufferIndex].Renderbuffer;
581 }
582 }
583
584
585 /**
586 * Update a gl_framebuffer's derived state.
587 *
588 * Specifically, update these framebuffer fields:
589 * _ColorDrawBuffers
590 * _NumColorDrawBuffers
591 * _ColorReadBuffer
592 *
593 * If the framebuffer is user-created, make sure it's complete.
594 *
595 * The following functions (at least) can effect framebuffer state:
596 * glReadBuffer, glDrawBuffer, glDrawBuffersARB, glFramebufferRenderbufferEXT,
597 * glRenderbufferStorageEXT.
598 */
599 static void
update_framebuffer(struct gl_context * ctx,struct gl_framebuffer * fb)600 update_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
601 {
602 if (_mesa_is_winsys_fbo(fb)) {
603 /* This is a window-system framebuffer */
604 /* Need to update the FB's GL_DRAW_BUFFER state to match the
605 * context state (GL_READ_BUFFER too).
606 */
607 if (fb->ColorDrawBuffer[0] != ctx->Color.DrawBuffer[0]) {
608 _mesa_drawbuffers(ctx, fb, ctx->Const.MaxDrawBuffers,
609 ctx->Color.DrawBuffer, NULL);
610 }
611
612 /* Call device driver function if fb is the bound draw buffer. */
613 if (fb == ctx->DrawBuffer) {
614 if (ctx->Driver.DrawBufferAllocate)
615 ctx->Driver.DrawBufferAllocate(ctx);
616 }
617 }
618 else {
619 /* This is a user-created framebuffer.
620 * Completeness only matters for user-created framebuffers.
621 */
622 if (fb->_Status != GL_FRAMEBUFFER_COMPLETE) {
623 _mesa_test_framebuffer_completeness(ctx, fb);
624 }
625 }
626
627 /* Strictly speaking, we don't need to update the draw-state
628 * if this FB is bound as ctx->ReadBuffer (and conversely, the
629 * read-state if this FB is bound as ctx->DrawBuffer), but no
630 * harm.
631 */
632 update_color_draw_buffers(fb);
633 update_color_read_buffer(fb);
634
635 compute_depth_max(fb);
636 }
637
638
639 /**
640 * Update state related to the draw/read framebuffers.
641 */
642 void
_mesa_update_framebuffer(struct gl_context * ctx,struct gl_framebuffer * readFb,struct gl_framebuffer * drawFb)643 _mesa_update_framebuffer(struct gl_context *ctx,
644 struct gl_framebuffer *readFb,
645 struct gl_framebuffer *drawFb)
646 {
647 assert(ctx);
648
649 update_framebuffer(ctx, drawFb);
650 if (readFb != drawFb)
651 update_framebuffer(ctx, readFb);
652
653 _mesa_update_clamp_vertex_color(ctx, drawFb);
654 _mesa_update_clamp_fragment_color(ctx, drawFb);
655 }
656
657
658 /**
659 * Check if the renderbuffer for a read/draw operation exists.
660 * \param format a basic image format such as GL_RGB, GL_RGBA, GL_ALPHA,
661 * GL_DEPTH_COMPONENT, etc. or GL_COLOR, GL_DEPTH, GL_STENCIL.
662 * \param reading if TRUE, we're going to read from the buffer,
663 if FALSE, we're going to write to the buffer.
664 * \return GL_TRUE if buffer exists, GL_FALSE otherwise
665 */
666 static GLboolean
renderbuffer_exists(struct gl_context * ctx,struct gl_framebuffer * fb,GLenum format,GLboolean reading)667 renderbuffer_exists(struct gl_context *ctx,
668 struct gl_framebuffer *fb,
669 GLenum format,
670 GLboolean reading)
671 {
672 const struct gl_renderbuffer_attachment *att = fb->Attachment;
673
674 /* If we don't know the framebuffer status, update it now */
675 if (fb->_Status == 0) {
676 _mesa_test_framebuffer_completeness(ctx, fb);
677 }
678
679 if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
680 return GL_FALSE;
681 }
682
683 switch (format) {
684 case GL_COLOR:
685 case GL_RED:
686 case GL_GREEN:
687 case GL_BLUE:
688 case GL_ALPHA:
689 case GL_LUMINANCE:
690 case GL_LUMINANCE_ALPHA:
691 case GL_INTENSITY:
692 case GL_RG:
693 case GL_RGB:
694 case GL_BGR:
695 case GL_RGBA:
696 case GL_BGRA:
697 case GL_ABGR_EXT:
698 case GL_RED_INTEGER_EXT:
699 case GL_RG_INTEGER:
700 case GL_GREEN_INTEGER_EXT:
701 case GL_BLUE_INTEGER_EXT:
702 case GL_ALPHA_INTEGER_EXT:
703 case GL_RGB_INTEGER_EXT:
704 case GL_RGBA_INTEGER_EXT:
705 case GL_BGR_INTEGER_EXT:
706 case GL_BGRA_INTEGER_EXT:
707 case GL_LUMINANCE_INTEGER_EXT:
708 case GL_LUMINANCE_ALPHA_INTEGER_EXT:
709 if (reading) {
710 /* about to read from a color buffer */
711 const struct gl_renderbuffer *readBuf = fb->_ColorReadBuffer;
712 if (!readBuf) {
713 return GL_FALSE;
714 }
715 assert(_mesa_get_format_bits(readBuf->Format, GL_RED_BITS) > 0 ||
716 _mesa_get_format_bits(readBuf->Format, GL_ALPHA_BITS) > 0 ||
717 _mesa_get_format_bits(readBuf->Format, GL_TEXTURE_LUMINANCE_SIZE) > 0 ||
718 _mesa_get_format_bits(readBuf->Format, GL_TEXTURE_INTENSITY_SIZE) > 0 ||
719 _mesa_get_format_bits(readBuf->Format, GL_INDEX_BITS) > 0);
720 }
721 else {
722 /* about to draw to zero or more color buffers (none is OK) */
723 return GL_TRUE;
724 }
725 break;
726 case GL_DEPTH:
727 case GL_DEPTH_COMPONENT:
728 if (att[BUFFER_DEPTH].Type == GL_NONE) {
729 return GL_FALSE;
730 }
731 break;
732 case GL_STENCIL:
733 case GL_STENCIL_INDEX:
734 if (att[BUFFER_STENCIL].Type == GL_NONE) {
735 return GL_FALSE;
736 }
737 break;
738 case GL_DEPTH_STENCIL_EXT:
739 if (att[BUFFER_DEPTH].Type == GL_NONE ||
740 att[BUFFER_STENCIL].Type == GL_NONE) {
741 return GL_FALSE;
742 }
743 break;
744 case GL_DEPTH_STENCIL_TO_RGBA_NV:
745 case GL_DEPTH_STENCIL_TO_BGRA_NV:
746 if (att[BUFFER_DEPTH].Type == GL_NONE ||
747 att[BUFFER_STENCIL].Type == GL_NONE) {
748 return GL_FALSE;
749 }
750 break;
751 default:
752 _mesa_problem(ctx,
753 "Unexpected format 0x%x in renderbuffer_exists",
754 format);
755 return GL_FALSE;
756 }
757
758 /* OK */
759 return GL_TRUE;
760 }
761
762
763 /**
764 * Check if the renderbuffer for a read operation (glReadPixels, glCopyPixels,
765 * glCopyTex[Sub]Image, etc) exists.
766 * \param format a basic image format such as GL_RGB, GL_RGBA, GL_ALPHA,
767 * GL_DEPTH_COMPONENT, etc. or GL_COLOR, GL_DEPTH, GL_STENCIL.
768 * \return GL_TRUE if buffer exists, GL_FALSE otherwise
769 */
770 GLboolean
_mesa_source_buffer_exists(struct gl_context * ctx,GLenum format)771 _mesa_source_buffer_exists(struct gl_context *ctx, GLenum format)
772 {
773 return renderbuffer_exists(ctx, ctx->ReadBuffer, format, GL_TRUE);
774 }
775
776
777 /**
778 * As above, but for drawing operations.
779 */
780 GLboolean
_mesa_dest_buffer_exists(struct gl_context * ctx,GLenum format)781 _mesa_dest_buffer_exists(struct gl_context *ctx, GLenum format)
782 {
783 return renderbuffer_exists(ctx, ctx->DrawBuffer, format, GL_FALSE);
784 }
785
786
787 /**
788 * Used to answer the GL_IMPLEMENTATION_COLOR_READ_FORMAT_OES queries (using
789 * GetIntegerv, GetFramebufferParameteriv, etc)
790 *
791 * If @fb is NULL, the method returns the value for the current bound
792 * framebuffer.
793 */
794 GLenum
_mesa_get_color_read_format(struct gl_context * ctx,struct gl_framebuffer * fb,const char * caller)795 _mesa_get_color_read_format(struct gl_context *ctx,
796 struct gl_framebuffer *fb,
797 const char *caller)
798 {
799 if (ctx->NewState)
800 _mesa_update_state(ctx);
801
802 if (fb == NULL)
803 fb = ctx->ReadBuffer;
804
805 if (!fb || !fb->_ColorReadBuffer) {
806 /*
807 * From OpenGL 4.5 spec, section 18.2.2 "ReadPixels":
808 *
809 * "An INVALID_OPERATION error is generated by GetIntegerv if pname
810 * is IMPLEMENTATION_COLOR_READ_FORMAT or IMPLEMENTATION_COLOR_-
811 * READ_TYPE and any of:
812 * * the read framebuffer is not framebuffer complete.
813 * * the read framebuffer is a framebuffer object, and the selected
814 * read buffer (see section 18.2.1) has no image attached.
815 * * the selected read buffer is NONE."
816 *
817 * There is not equivalent quote for GetFramebufferParameteriv or
818 * GetNamedFramebufferParameteriv, but from section 9.2.3 "Framebuffer
819 * Object Queries":
820 *
821 * "Values of framebuffer-dependent state are identical to those that
822 * would be obtained were the framebuffer object bound and queried
823 * using the simple state queries in that table."
824 *
825 * Where "using the simple state queries" refer to use GetIntegerv. So
826 * we will assume that on that situation the same error should be
827 * triggered too.
828 */
829 _mesa_error(ctx, GL_INVALID_OPERATION,
830 "%s(GL_IMPLEMENTATION_COLOR_READ_FORMAT: no GL_READ_BUFFER)",
831 caller);
832 return GL_NONE;
833 }
834 else {
835 const mesa_format format = fb->_ColorReadBuffer->Format;
836
837 switch (format) {
838 case MESA_FORMAT_RGBA_UINT8:
839 return GL_RGBA_INTEGER;
840 case MESA_FORMAT_B8G8R8A8_UNORM:
841 return GL_BGRA;
842 case MESA_FORMAT_B5G6R5_UNORM:
843 case MESA_FORMAT_R11G11B10_FLOAT:
844 return GL_RGB;
845 case MESA_FORMAT_RG_FLOAT32:
846 case MESA_FORMAT_RG_FLOAT16:
847 case MESA_FORMAT_RG_UNORM8:
848 return GL_RG;
849 case MESA_FORMAT_RG_SINT32:
850 case MESA_FORMAT_RG_UINT32:
851 case MESA_FORMAT_RG_SINT16:
852 case MESA_FORMAT_RG_UINT16:
853 case MESA_FORMAT_RG_SINT8:
854 case MESA_FORMAT_RG_UINT8:
855 return GL_RG_INTEGER;
856 case MESA_FORMAT_R_FLOAT32:
857 case MESA_FORMAT_R_FLOAT16:
858 case MESA_FORMAT_R_UNORM16:
859 case MESA_FORMAT_R_UNORM8:
860 case MESA_FORMAT_R_SNORM16:
861 case MESA_FORMAT_R_SNORM8:
862 return GL_RED;
863 case MESA_FORMAT_R_SINT32:
864 case MESA_FORMAT_R_UINT32:
865 case MESA_FORMAT_R_SINT16:
866 case MESA_FORMAT_R_UINT16:
867 case MESA_FORMAT_R_SINT8:
868 case MESA_FORMAT_R_UINT8:
869 return GL_RED_INTEGER;
870 default:
871 break;
872 }
873
874 if (_mesa_is_format_integer(format))
875 return GL_RGBA_INTEGER;
876 else
877 return GL_RGBA;
878 }
879 }
880
881
882 /**
883 * Used to answer the GL_IMPLEMENTATION_COLOR_READ_TYPE_OES queries (using
884 * GetIntegerv, GetFramebufferParameteriv, etc)
885 *
886 * If @fb is NULL, the method returns the value for the current bound
887 * framebuffer.
888 */
889 GLenum
_mesa_get_color_read_type(struct gl_context * ctx,struct gl_framebuffer * fb,const char * caller)890 _mesa_get_color_read_type(struct gl_context *ctx,
891 struct gl_framebuffer *fb,
892 const char *caller)
893 {
894 if (ctx->NewState)
895 _mesa_update_state(ctx);
896
897 if (fb == NULL)
898 fb = ctx->ReadBuffer;
899
900 if (!fb || !fb->_ColorReadBuffer) {
901 /*
902 * See comment on _mesa_get_color_read_format
903 */
904 _mesa_error(ctx, GL_INVALID_OPERATION,
905 "%s(GL_IMPLEMENTATION_COLOR_READ_TYPE: no GL_READ_BUFFER)",
906 caller);
907 return GL_NONE;
908 }
909 else {
910 const mesa_format format = fb->_ColorReadBuffer->Format;
911 GLenum data_type;
912 GLuint comps;
913
914 _mesa_uncompressed_format_to_type_and_comps(format, &data_type, &comps);
915
916 return data_type;
917 }
918 }
919
920
921 /**
922 * Returns the read renderbuffer for the specified format.
923 */
924 struct gl_renderbuffer *
_mesa_get_read_renderbuffer_for_format(const struct gl_context * ctx,GLenum format)925 _mesa_get_read_renderbuffer_for_format(const struct gl_context *ctx,
926 GLenum format)
927 {
928 const struct gl_framebuffer *rfb = ctx->ReadBuffer;
929
930 if (_mesa_is_color_format(format)) {
931 return rfb->Attachment[rfb->_ColorReadBufferIndex].Renderbuffer;
932 } else if (_mesa_is_depth_format(format) ||
933 _mesa_is_depthstencil_format(format)) {
934 return rfb->Attachment[BUFFER_DEPTH].Renderbuffer;
935 } else {
936 return rfb->Attachment[BUFFER_STENCIL].Renderbuffer;
937 }
938 }
939
940
941 /**
942 * Print framebuffer info to stderr, for debugging.
943 */
944 void
_mesa_print_framebuffer(const struct gl_framebuffer * fb)945 _mesa_print_framebuffer(const struct gl_framebuffer *fb)
946 {
947 fprintf(stderr, "Mesa Framebuffer %u at %p\n", fb->Name, (void *) fb);
948 fprintf(stderr, " Size: %u x %u Status: %s\n", fb->Width, fb->Height,
949 _mesa_enum_to_string(fb->_Status));
950 fprintf(stderr, " Attachments:\n");
951
952 for (unsigned i = 0; i < BUFFER_COUNT; i++) {
953 const struct gl_renderbuffer_attachment *att = &fb->Attachment[i];
954 if (att->Type == GL_TEXTURE) {
955 const struct gl_texture_image *texImage = att->Renderbuffer->TexImage;
956 fprintf(stderr,
957 " %2d: Texture %u, level %u, face %u, slice %u, complete %d\n",
958 i, att->Texture->Name, att->TextureLevel, att->CubeMapFace,
959 att->Zoffset, att->Complete);
960 fprintf(stderr, " Size: %u x %u x %u Format %s\n",
961 texImage->Width, texImage->Height, texImage->Depth,
962 _mesa_get_format_name(texImage->TexFormat));
963 }
964 else if (att->Type == GL_RENDERBUFFER) {
965 fprintf(stderr, " %2d: Renderbuffer %u, complete %d\n",
966 i, att->Renderbuffer->Name, att->Complete);
967 fprintf(stderr, " Size: %u x %u Format %s\n",
968 att->Renderbuffer->Width, att->Renderbuffer->Height,
969 _mesa_get_format_name(att->Renderbuffer->Format));
970 }
971 else {
972 fprintf(stderr, " %2d: none\n", i);
973 }
974 }
975 }
976
977 bool
_mesa_is_front_buffer_reading(const struct gl_framebuffer * fb)978 _mesa_is_front_buffer_reading(const struct gl_framebuffer *fb)
979 {
980 if (!fb || _mesa_is_user_fbo(fb))
981 return false;
982
983 return fb->_ColorReadBufferIndex == BUFFER_FRONT_LEFT;
984 }
985
986 bool
_mesa_is_front_buffer_drawing(const struct gl_framebuffer * fb)987 _mesa_is_front_buffer_drawing(const struct gl_framebuffer *fb)
988 {
989 if (!fb || _mesa_is_user_fbo(fb))
990 return false;
991
992 return (fb->_NumColorDrawBuffers >= 1 &&
993 fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT);
994 }
995
996 static inline GLuint
_mesa_geometric_nonvalidated_samples(const struct gl_framebuffer * buffer)997 _mesa_geometric_nonvalidated_samples(const struct gl_framebuffer *buffer)
998 {
999 return buffer->_HasAttachments ?
1000 buffer->Visual.samples :
1001 buffer->DefaultGeometry.NumSamples;
1002 }
1003
1004 bool
_mesa_is_multisample_enabled(const struct gl_context * ctx)1005 _mesa_is_multisample_enabled(const struct gl_context *ctx)
1006 {
1007 /* The sample count may not be validated by the driver, but when it is set,
1008 * we know that is in a valid range and no driver should ever validate a
1009 * multisampled framebuffer to non-multisampled and vice-versa.
1010 */
1011 return ctx->Multisample.Enabled &&
1012 ctx->DrawBuffer &&
1013 _mesa_geometric_nonvalidated_samples(ctx->DrawBuffer) >= 1;
1014 }
1015
1016 /**
1017 * Is alpha testing enabled and applicable to the currently bound
1018 * framebuffer?
1019 */
1020 bool
_mesa_is_alpha_test_enabled(const struct gl_context * ctx)1021 _mesa_is_alpha_test_enabled(const struct gl_context *ctx)
1022 {
1023 bool buffer0_is_integer = ctx->DrawBuffer->_IntegerBuffers & 0x1;
1024 return (ctx->Color.AlphaEnabled && !buffer0_is_integer);
1025 }
1026
1027 /**
1028 * Is alpha to coverage enabled and applicable to the currently bound
1029 * framebuffer?
1030 */
1031 bool
_mesa_is_alpha_to_coverage_enabled(const struct gl_context * ctx)1032 _mesa_is_alpha_to_coverage_enabled(const struct gl_context *ctx)
1033 {
1034 bool buffer0_is_integer = ctx->DrawBuffer->_IntegerBuffers & 0x1;
1035 return (ctx->Multisample.SampleAlphaToCoverage &&
1036 _mesa_is_multisample_enabled(ctx) &&
1037 !buffer0_is_integer);
1038 }
1039