942951 - WebGL assertion failure as WebGLContext::GetBitsPerTexel hits unexpected format GL_RGB32F

Status: RESOLVED FIXED

(Core :: Graphics: CanvasWebGL, defect)

Description

[Benoit Jacob [:bjacob] (mostly away)]

STR:
 1. Make a *debug* build
 2. Visit WebGL Pasta: http://alteredqualia.com/three/examples/webgl_pasta.html
 3. Go to about:memory and hit 'measure'

Result: assertion failure:

#5  <signal handler called>
#6  0x00007f36be42f0df in mozilla::WebGLContext::GetBitsPerTexel (format=34837, type=5126) at /hack/mozilla-central/content/canvas/src/WebGLContextValidate.cpp:522
#7  0x00007f36be447ef5 in mozilla::WebGLTexture::ImageInfo::MemoryUsage (this=0x7f3694019b28) at /hack/mozilla-central/content/canvas/src/WebGLTexture.cpp:51
#8  0x00007f36be447fef in mozilla::WebGLTexture::MemoryUsage (this=0x7f36940d6060) at /hack/mozilla-central/content/canvas/src/WebGLTexture.cpp:68
#9  0x00007f36be43638a in mozilla::WebGLMemoryReporterWrapper::GetTextureMemoryUsed () at /hack/mozilla-central/content/canvas/src/WebGLMemoryReporterWrapper.h:72
#10 0x00007f36be42a733 in WebGLMemoryReporter::CollectReports (this=0x7f368e727c70, aCb=0x7f365ec85460, aClosure=0x0) at /hack/mozilla-central/content/canvas/src/WebGLContextReporter.cpp:38

(gdb) frame 6
#6  0x00007f36be42f0df in mozilla::WebGLContext::GetBitsPerTexel (format=34837, type=5126) at /hack/mozilla-central/content/canvas/src/WebGLContextValidate.cpp:522
522         MOZ_ASSERT(false);
(gdb) l 460
455             ErrorInvalidValue("%s: width and height must be >= 0", info);
456             return false;
457         }
458
459         if (width > maxAllowedSize || height > maxAllowedSize) {
460             ErrorInvalidValue("%s: the maximum texture size for level %d is %d", info, level, maxAllowedSize);
461             return false;
462         }
463
464         return true;
(gdb) 
465     }
466
467     uint32_t WebGLContext::GetBitsPerTexel(GLenum format, GLenum type)
468     {
469         // If there is no defined format or type, we're not taking up any memory
470         if (!format || !type) {
471             return 0;
472         }
473
474         if (format == LOCAL_GL_DEPTH_COMPONENT) {
(gdb) 
475             if (type == LOCAL_GL_UNSIGNED_SHORT)
476                 return 2;
477             else if (type == LOCAL_GL_UNSIGNED_INT)
478                 return 4;
479         } else if (format == LOCAL_GL_DEPTH_STENCIL) {
480             if (type == LOCAL_GL_UNSIGNED_INT_24_8_EXT)
481                 return 4;
482         }
483
484         if (type == LOCAL_GL_UNSIGNED_BYTE || type == LOCAL_GL_FLOAT) {
(gdb) 
485             int multiplier = type == LOCAL_GL_FLOAT ? 32 : 8;
486             switch (format) {
487                 case LOCAL_GL_ALPHA:
488                 case LOCAL_GL_LUMINANCE:
489                     return 1 * multiplier;
490                 case LOCAL_GL_LUMINANCE_ALPHA:
491                     return 2 * multiplier;
492                 case LOCAL_GL_RGB:
493                 case LOCAL_GL_SRGB_EXT:
494                     return 3 * multiplier;
(gdb) 
495                 case LOCAL_GL_RGBA:
496                 case LOCAL_GL_SRGB_ALPHA_EXT:
497                     return 4 * multiplier;
498                 case LOCAL_GL_COMPRESSED_RGB_PVRTC_2BPPV1:
499                 case LOCAL_GL_COMPRESSED_RGBA_PVRTC_2BPPV1:
500                     return 2;
501                 case LOCAL_GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
502                 case LOCAL_GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
503                 case LOCAL_GL_ATC_RGB:
504                 case LOCAL_GL_COMPRESSED_RGB_PVRTC_4BPPV1:
(gdb) 
505                 case LOCAL_GL_COMPRESSED_RGBA_PVRTC_4BPPV1:
506                     return 4;
507                 case LOCAL_GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
508                 case LOCAL_GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
509                 case LOCAL_GL_ATC_RGBA_EXPLICIT_ALPHA:
510                 case LOCAL_GL_ATC_RGBA_INTERPOLATED_ALPHA:
511                     return 8;
512                 default:
513                     break;
514             }
(gdb) 
515         } else if (type == LOCAL_GL_UNSIGNED_SHORT_4_4_4_4 ||
516                    type == LOCAL_GL_UNSIGNED_SHORT_5_5_5_1 ||
517                    type == LOCAL_GL_UNSIGNED_SHORT_5_6_5)
518         {
519             return 16;
520         }
521
522         MOZ_ASSERT(false);  // ### CRASH HERE! ###
523         return 0;
524     }


(gdb) p/x format
$7 = 0x8815           // GL_RGB32F
(gdb) p/x type
$8 = 0x1406           // GL_FLOAT


The question is how did we end up with GL_RGB32F as the format here? That is not a valid 'format' parameter to WebGL.texImage2D, even with OES_TEXTURE_FLOAT.

Is this a format/internalformat mismatch i.e. are we recording an internalformat of RGB32F here? If yes, does the present function need to be updated to accept such internalformat values?

Comment 1

[u480271]

Benoit,

Following the STR I was unable to reproduce. Is there more to it?

Comment 2

[Benoit Jacob [:bjacob] (mostly away)]

OK, nevermind then, thanks for trying, but if this doesn't reproduce for you then there's probably nothing that you can do about this bug; I'll try to take a look.

Comment 3

[Kelsey Gilbert [:jgilbert]]

I can repro.

Comment 4

[Kelsey Gilbert [:jgilbert]]

Attachment: float-mem

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/b50e11876aee

Please make sure that future patches include a commit message when requesting checkin.

Comment 6

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/b50e11876aee