36366 2010-03-19 07:26:23 -0700 Repaint loop when painting using scaled CTMs with different translations 2010-03-19 08:34:39 -0700 1 1 1 Unclassified WebKit Layout and Rendering 528+ (Nightly build) PC OS X 10.5 RESOLVED FIXED P2 Normal --- 1 koivisto webkit-unassigned hausmann manyoso oliver oldest_to_newest 201845 0 koivisto 2010-03-19 07:26:23 -0700 The code in RenderBoxModelScaleObserver::shouldPaintBackgroundAtLowQuality tests if the scaling has changed from the previous value by comparing the transformations: // We are scaled, but we painted already at this size, so just keep using whatever mode we last painted with. if ((!contextIsScaled || data->transform() == currentTransform) && data->size() == size) return data->useLowQualityScale(); This test fails if the scale is the same but the translation changes. This can lead to infinite repaint loop, if the document is painted in pieces using different translations (for example for tiling). 201850 1 51154 koivisto 2010-03-19 07:56:01 -0700 Created attachment 51154 patch 201862 2 51154 hausmann 2010-03-19 08:26:46 -0700 Comment on attachment 51154 patch Landing manually 201863 3 hausmann 2010-03-19 08:28:29 -0700 Committed r56239: <http://trac.webkit.org/changeset/56239> 51154 2010-03-19 07:56:01 -0700 2010-03-19 08:26:46 -0700 patch low-quality-background-transform.patch text/plain 2068 koivisto SW5kZXg6IFdlYkNvcmUvQ2hhbmdlTG9nCj09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09 PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT0KLS0tIFdlYkNvcmUvQ2hhbmdlTG9n CShyZXZpc2lvbiA1NjIzNykKKysrIFdlYkNvcmUvQ2hhbmdlTG9nCSh3b3JraW5nIGNvcHkpCkBA IC0xLDMgKzEsMTkgQEAKKzIwMTAtMDMtMTkgIEFudHRpIEtvaXZpc3RvICA8a29pdmlzdG9AaWtp LmZpPgorCisgICAgICAgIFJldmlld2VkIGJ5IE5PQk9EWSAoT09QUyEpLgorCisgICAgICAgIGh0 dHBzOi8vYnVncy53ZWJraXQub3JnL3Nob3dfYnVnLmNnaT9pZD0zNjM2NgorICAgICAgICBSZXBh aW50IGxvb3Agd2hlbiBwYWludGluZyB1c2luZyBzY2FsZWQgQ1RNcyB3aXRoIGRpZmZlcmVudCB0 cmFuc2xhdGlvbnMKKyAgICAgICAgCisgICAgICAgIFRoZSBjb2RlIGluIFJlbmRlckJveE1vZGVs U2NhbGVPYnNlcnZlcjo6c2hvdWxkUGFpbnRCYWNrZ3JvdW5kQXRMb3dRdWFsaXR5CisgICAgICAg IHRlc3RzIGlmIHRoZSBzY2FsaW5nIGhhcyBjaGFuZ2VkIGZyb20gdGhlIHByZXZpb3VzIHZhbHVl IGJ5IGNvbXBhcmluZyB0aGUKKyAgICAgICAgdHJhbnNmb3JtYXRpb25zLiBUaGUgdGVzdCBmYWls cyBpZiB0aGUgc2NhbGUgaXMgdGhlIHNhbWUgYnV0IHRoZSB0cmFuc2xhdGlvbiAKKyAgICAgICAg Y2hhbmdlcy4gVGhpcyBjYW4gbGVhZCB0byBpbmZpbml0ZSByZXBhaW50IGxvb3AgaWYgdGhlIGRv Y3VtZW50IGlzIHBhaW50ZWQgCisgICAgICAgIGluIHBpZWNlcyB1c2luZyBkaWZmZXJlbnQgdHJh bnNsYXRpb25zIChmb3IgZXhhbXBsZSBmb3IgdGlsaW5nKS4KKworICAgICAgICAqIHJlbmRlcmlu Zy9SZW5kZXJCb3hNb2RlbE9iamVjdC5jcHA6CisgICAgICAgIChXZWJDb3JlOjpSZW5kZXJCb3hN b2RlbFNjYWxlT2JzZXJ2ZXI6OnNob3VsZFBhaW50QmFja2dyb3VuZEF0TG93UXVhbGl0eSk6CisK IDIwMTAtMDMtMTkgIFBhdmVsIEZlbGRtYW4gIDxwZmVsZG1hbkBjaHJvbWl1bS5vcmc+CiAKICAg ICAgICAgUmV2aWV3ZWQgYnkgVGltb3RoeSBIYXRjaGVyLgpJbmRleDogV2ViQ29yZS9yZW5kZXJp bmcvUmVuZGVyQm94TW9kZWxPYmplY3QuY3BwCj09PT09PT09PT09PT09PT09PT09PT09PT09PT09 PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT0KLS0tIFdlYkNvcmUvcmVuZGVy aW5nL1JlbmRlckJveE1vZGVsT2JqZWN0LmNwcAkocmV2aXNpb24gNTYyMzUpCisrKyBXZWJDb3Jl L3JlbmRlcmluZy9SZW5kZXJCb3hNb2RlbE9iamVjdC5jcHAJKHdvcmtpbmcgY29weSkKQEAgLTE1 OCw4ICsxNTgsMTAgQEAgYm9vbCBSZW5kZXJCb3hNb2RlbFNjYWxlT2JzZXJ2ZXI6OnNob3VsZAog ICAgICAgICByZXR1cm4gZmFsc2U7CiAgICAgfQogCisgICAgY29uc3QgQWZmaW5lVHJhbnNmb3Jt JiB0ciA9IGRhdGEtPnRyYW5zZm9ybSgpOworICAgIGJvb2wgc2NhbGVVbmNoYW5nZWQgPSB0ci5h KCkgPT0gY3VycmVudFRyYW5zZm9ybS5hKCkgJiYgdHIuYigpID09IGN1cnJlbnRUcmFuc2Zvcm0u YigpICYmIHRyLmMoKSA9PSBjdXJyZW50VHJhbnNmb3JtLmMoKSAmJiB0ci5kKCkgPT0gY3VycmVu dFRyYW5zZm9ybS5kKCk7CiAgICAgLy8gV2UgYXJlIHNjYWxlZCwgYnV0IHdlIHBhaW50ZWQgYWxy ZWFkeSBhdCB0aGlzIHNpemUsIHNvIGp1c3Qga2VlcCB1c2luZyB3aGF0ZXZlciBtb2RlIHdlIGxh c3QgcGFpbnRlZCB3aXRoLgotICAgIGlmICgoIWNvbnRleHRJc1NjYWxlZCB8fCBkYXRhLT50cmFu c2Zvcm0oKSA9PSBjdXJyZW50VHJhbnNmb3JtKSAmJiBkYXRhLT5zaXplKCkgPT0gc2l6ZSkKKyAg ICBpZiAoKCFjb250ZXh0SXNTY2FsZWQgfHwgc2NhbGVVbmNoYW5nZWQpICYmIGRhdGEtPnNpemUo KSA9PSBzaXplKQogICAgICAgICByZXR1cm4gZGF0YS0+dXNlTG93UXVhbGl0eVNjYWxlKCk7CiAK ICAgICAvLyBXZSBoYXZlIGRhdGEgYW5kIG91ciBzaXplIGp1c3QgY2hhbmdlZC4gIElmIHRoaXMg Y2hhbmdlIGhhcHBlbmVkIHF1aWNrbHksIGdvIGludG8gbG93IHF1YWxpdHkgbW9kZSBhbmQgdGhl biBzZXQgYSByZXBhaW50Cg==