73228 2011-11-28 10:29:33 -0800 Synchronization problem in Canvas/WebGLRenderingContext when listener asks for image 2011-11-28 17:38:51 -0800 1 1 1 Unclassified WebKit New Bugs 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 danakj danakj backer kbr piman webkit.review.bot oldest_to_newest 509932 0 danakj 2011-11-28 10:29:33 -0800 If a listener to HTMLCanvasElement contentChanged asks for the current image, the canvas will stop updating its contents forever. Two classes: HTMLCanvasElement || WebGLRenderingContext ----------------------GOOD------------------------------ ask for image here ----> paints onto canvas marks NOT DIRTY (ie nothing new to send to canvas) saves cache <---- ----------------------GOOD------------------------------ new stuff in webgl clears cache <---- marks DIRTY (stuff to be painted in canvas) ----------------------BAD------------------------------- new stuff in webgl clears cache <---- notify people ask for image here ----> paints onto canvas marks NOT DIRTY (ie nothing new to send to canvas) saves cache <---- marks DIRTY (stuff to be painted in canvas) Now there is a cached image, so it will never paint onto canvas again. And the canvas is marked dirty so WebGL will never draw onto it again. Each is waiting for the other. 509941 1 116780 danakj 2011-11-28 10:40:47 -0800 Created attachment 116780 Patch 509945 2 danakj 2011-11-28 10:44:57 -0800 This patch: Since the cached image is cleared before notifying people about the change, mark the canvas dirty before also. This a) keeps them in sync. b) if a listener requests the image, it will cache the requested version correctly. An alternate version of this patch would be to clear the cache and mark dirty after notifying listeners. In b) above, this would throw away the cache and cause extra work in the next request for the image. 510129 3 kbr 2011-11-28 13:41:31 -0800 Have you run the preserveDrawingBuffer related tests in fast/canvas/webgl with these changes, both in DRT and in the browser? Have you verified that printing of WebGL content works after this change? 510161 4 danakj 2011-11-28 14:13:09 -0800 (In reply to comment #3) > Have you run the preserveDrawingBuffer related tests in fast/canvas/webgl with these changes, both in DRT and in the browser? All of fast/canvas/webgl passes with platform chromium-linux and chromium-gpu. fast/canvas/webgl/premultiplyalpha-test.html passes in the browser. > Have you verified that printing of WebGL content works after this change? Printing WebGL aquarium to a PDF worked. 510176 5 116780 kbr 2011-11-28 14:27:54 -0800 Comment on attachment 116780 Patch OK. The patch looks fine otherwise. r=me 510369 6 116780 webkit.review.bot 2011-11-28 17:38:47 -0800 Comment on attachment 116780 Patch Clearing flags on attachment: 116780 Committed r101311: <http://trac.webkit.org/changeset/101311> 510370 7 webkit.review.bot 2011-11-28 17:38:51 -0800 All reviewed patches have been landed. Closing bug. 116780 2011-11-28 10:40:47 -0800 2011-11-28 17:38:47 -0800 Patch bug-73228-20111128134046.patch text/plain 1969 danakj U3VidmVyc2lvbiBSZXZpc2lvbjogMTAxMjYzCmRpZmYgLS1naXQgYS9Tb3VyY2UvV2ViQ29yZS9D aGFuZ2VMb2cgYi9Tb3VyY2UvV2ViQ29yZS9DaGFuZ2VMb2cKaW5kZXggYmUwYjdmNGUxM2M0NmE0 ODlkMTE0MGIzNjkzYjYxZWYyNzMyNzU2Ni4uMzU0YzdjYzA2YjQ1NzZkNTgxMjU1ODMzZjQ4M2Nh ZGFhNGVjMWRiNCAxMDA2NDQKLS0tIGEvU291cmNlL1dlYkNvcmUvQ2hhbmdlTG9nCisrKyBiL1Nv dXJjZS9XZWJDb3JlL0NoYW5nZUxvZwpAQCAtMSwzICsxLDEzIEBACisyMDExLTExLTI4ICBEYW5h IEphbnNlbnMgIDxkYW5ha2pAY2hyb21pdW0ub3JnPgorCisgICAgICAgIFN5bmNocm9uaXphdGlv biBwcm9ibGVtIGluIENhbnZhcy9XZWJHTFJlbmRlcmluZ0NvbnRleHQgd2hlbiBsaXN0ZW5lciBh c2tzIGZvciBpbWFnZQorICAgICAgICBodHRwczovL2J1Z3Mud2Via2l0Lm9yZy9zaG93X2J1Zy5j Z2k/aWQ9NzMyMjgKKworICAgICAgICBSZXZpZXdlZCBieSBOT0JPRFkgKE9PUFMhKS4KKworICAg ICAgICAqIGh0bWwvY2FudmFzL1dlYkdMUmVuZGVyaW5nQ29udGV4dC5jcHA6CisgICAgICAgIChX ZWJDb3JlOjpXZWJHTFJlbmRlcmluZ0NvbnRleHQ6Om1hcmtDb250ZXh0Q2hhbmdlZCk6CisKIDIw MTEtMTEtMjggIEFuZHJlYXMgS2xpbmcgIDxrbGluZ0B3ZWJraXQub3JnPgogCiAgICAgICAgIElu c3BlY3RvckNTU0FnZW50OiBSZW1vdmUgdW51c2VkIGZ1bmN0aW9uIGlubGluZVN0eWxlRWxlbWVu dCgpLgpkaWZmIC0tZ2l0IGEvU291cmNlL1dlYkNvcmUvaHRtbC9jYW52YXMvV2ViR0xSZW5kZXJp bmdDb250ZXh0LmNwcCBiL1NvdXJjZS9XZWJDb3JlL2h0bWwvY2FudmFzL1dlYkdMUmVuZGVyaW5n Q29udGV4dC5jcHAKaW5kZXggMzBiOGZmNjE3ZmM0MDMyZjI0MmQ0ZmYzMTk0ODRjMTE1MDRiYTlk NS4uYzhjM2NiYTUzNjg1Mzc5YzhlZWFkNDMxYzhhODBlMzc2MWI2MjI5OSAxMDA2NDQKLS0tIGEv U291cmNlL1dlYkNvcmUvaHRtbC9jYW52YXMvV2ViR0xSZW5kZXJpbmdDb250ZXh0LmNwcAorKysg Yi9Tb3VyY2UvV2ViQ29yZS9odG1sL2NhbnZhcy9XZWJHTFJlbmRlcmluZ0NvbnRleHQuY3BwCkBA IC01NDEsMTYgKzU0MSwxOCBAQCB2b2lkIFdlYkdMUmVuZGVyaW5nQ29udGV4dDo6bWFya0NvbnRl eHRDaGFuZ2VkKCkKICAgICBtX2xheWVyQ2xlYXJlZCA9IGZhbHNlOwogI2lmIFVTRShBQ0NFTEVS QVRFRF9DT01QT1NJVElORykKICAgICBSZW5kZXJCb3gqIHJlbmRlckJveCA9IGNhbnZhcygpLT5y ZW5kZXJCb3goKTsKLSAgICBpZiAocmVuZGVyQm94ICYmIHJlbmRlckJveC0+aGFzTGF5ZXIoKSAm JiByZW5kZXJCb3gtPmxheWVyKCktPmhhc0FjY2VsZXJhdGVkQ29tcG9zaXRpbmcoKSkKKyAgICBp ZiAocmVuZGVyQm94ICYmIHJlbmRlckJveC0+aGFzTGF5ZXIoKSAmJiByZW5kZXJCb3gtPmxheWVy KCktPmhhc0FjY2VsZXJhdGVkQ29tcG9zaXRpbmcoKSkgeworICAgICAgICBtX21hcmtlZENhbnZh c0RpcnR5ID0gdHJ1ZTsKICAgICAgICAgcmVuZGVyQm94LT5sYXllcigpLT5jb250ZW50Q2hhbmdl ZChSZW5kZXJMYXllcjo6Q2FudmFzQ2hhbmdlZCk7Ci0gICAgZWxzZSB7CisgICAgfSBlbHNlIHsK ICNlbmRpZgotICAgICAgICBpZiAoIW1fbWFya2VkQ2FudmFzRGlydHkpCisgICAgICAgIGlmICgh bV9tYXJrZWRDYW52YXNEaXJ0eSkgeworICAgICAgICAgICAgbV9tYXJrZWRDYW52YXNEaXJ0eSA9 IHRydWU7CiAgICAgICAgICAgICBjYW52YXMoKS0+ZGlkRHJhdyhGbG9hdFJlY3QoMCwgMCwgY2Fu dmFzKCktPndpZHRoKCksIGNhbnZhcygpLT5oZWlnaHQoKSkpOworICAgICAgICB9CiAjaWYgVVNF KEFDQ0VMRVJBVEVEX0NPTVBPU0lUSU5HKQogICAgIH0KICNlbmRpZgotICAgIG1fbWFya2VkQ2Fu dmFzRGlydHkgPSB0cnVlOwogfQogCiBib29sIFdlYkdMUmVuZGVyaW5nQ29udGV4dDo6Y2xlYXJJ ZkNvbXBvc2l0ZWQoR0MzRGJpdGZpZWxkIG1hc2spCg==