Bug 98205 – Round image sizes when zooming

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Emil A Eklund]

We currently floor image sizes when zooming which can result in images being rendered at one pixel less than the actual size. This is especially likely to happen for very large images.

Downstream webkit bug: http://code.google.com/p/chromium/issues/detail?id=150802

[Emil A Eklund]

Created attachment 166757 [details]
Patch

[Eric Seidel (no email)]

Comment on attachment 166757 [details]
Patch

LayoutTests/platform/chromium-linux/svg/zoom/page/zoom-svg-through-object-with-percentage-size-expected.png looks like they aren't quite in the same y-offset after zooming?

[Emil A Eklund]

The(In reply to comment #2)
> (From update of attachment 166757 [details])
> LayoutTests/platform/chromium-linux/svg/zoom/page/zoom-svg-through-object-with-percentage-size-expected.png looks like they aren't quite in the same y-offset after zooming?

Correct. This patch doesn't change that though, it only changes the size of the image to that it is the same size as the svg element.

[Build Bot]

Comment on attachment 166757 [details]
Patch

Attachment 166757 [details] did not pass mac-ews (mac):
Output: http://queues.webkit.org/results/14123568

New failing tests:
svg/zoom/page/zoom-svg-through-object-with-percentage-size.xhtml
svg/zoom/page/zoom-svg-through-object-with-absolute-size-2.xhtml
fast/sub-pixel/zoomed-image-tiles.html
svg/zoom/page/zoom-svg-through-object-with-absolute-size.xhtml

[Emil A Eklund]

Created attachment 166941 [details]
Patch

[Eric Seidel (no email)]

Comment on attachment 166941 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=166941&action=review

OK.

> Source/WebCore/loader/cache/CachedImage.cpp:268
> +    imageSize.setWidth(lroundf(imageSize.width() * widthScale));
> +    imageSize.setHeight(lroundf(imageSize.height() * heightScale));

We could have also written this in terms of LayoutUnit primatives and done this w/o #ifdefs. :)

[Emil A Eklund]

(In reply to comment #6)
> (From update of attachment 166941 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=166941&action=review
> 
> OK.
> 
> > Source/WebCore/loader/cache/CachedImage.cpp:268
> > +    imageSize.setWidth(lroundf(imageSize.width() * widthScale));
> > +    imageSize.setHeight(lroundf(imageSize.height() * heightScale));
> 
> We could have also written this in terms of LayoutUnit primatives and done this w/o #ifdefs. :)

I'd rather keep it as a IntSize as we need to represent images that way but yeah, I suppose we could have.

[Emil A Eklund]

Committed r130329: <http://trac.webkit.org/changeset/130329>