Subpixel rendering: Nested layers with subpixel accumulation paint to wrong position.

[zalan]

Subpixels need to be accumulated through nested layer to calculate correct painting positing.

[zalan]

Created attachment 226551 [details]
Patch

[Csaba Osztrogonác]

Comment on attachment 226551 [details]
Patch

Clearing flags on attachment: 226551

Committed r165540: <http://trac.webkit.org/changeset/165540>

[Csaba Osztrogonác]

All reviewed patches have been landed.  Closing bug.

[WebKit Commit Bot]

Re-opened since this is blocked by bug 130199

[Build Bot]

Comment on attachment 226551 [details]
Patch

Attachment 226551 [details] did not pass mac-ews (mac):
Output: http://webkit-queues.appspot.com/results/6741007710289920

New failing tests:
compositing/hidpi-absolute-subpixel-positioned-transformed-elements.html

[Build Bot]

Created attachment 226642 [details]
Archive of layout-test-results from webkit-ews-08 for mac-mountainlion

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: webkit-ews-08  Port: mac-mountainlion  Platform: Mac OS X 10.8.5

[Build Bot]

Comment on attachment 226551 [details]
Patch

Attachment 226551 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.appspot.com/results/4589675771592704

New failing tests:
compositing/hidpi-absolute-subpixel-positioned-transformed-elements.html

[Build Bot]

Created attachment 226645 [details]
Archive of layout-test-results from webkit-ews-15 for mac-mountainlion-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: webkit-ews-15  Port: mac-mountainlion-wk2  Platform: Mac OS X 10.8.5

[zalan]

Created attachment 227145 [details]
Patch

[Simon Fraser (smfr)]

Comment on attachment 227145 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=227145&action=review

> Source/WebCore/rendering/RenderLayer.cpp:4176
> +    // Translate the graphics context to the snapping position to avoid off-device-pixel positing. This works as long as the user defined
> +    // transform is not producing subpixel results (translate(0.5px, 0.5px) vs. translate(0.7px, 0.7px))

"This works as long as" isn't really adding information here, and it's not clear what "works" means. I'd remove this second sentence.

[zalan]

(In reply to comment #10)
> (From update of attachment 227145 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=227145&action=review
> 
> > Source/WebCore/rendering/RenderLayer.cpp:4176
> > +    // Translate the graphics context to the snapping position to avoid off-device-pixel positing. This works as long as the user defined
> > +    // transform is not producing subpixel results (translate(0.5px, 0.5px) vs. translate(0.7px, 0.7px))
> 
> "This works as long as" isn't really adding information here, and it's not clear what "works" means. I'd remove this second sentence.
Indeed. Thanks for the review.

[zalan]

Created attachment 227242 [details]
Patch

[zalan]

Comment on attachment 227242 [details]
Patch

EWS testing.

[WebKit Commit Bot]

Comment on attachment 227242 [details]
Patch

Clearing flags on attachment: 227242

Committed r165963: <http://trac.webkit.org/changeset/165963>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.