[webkit-reviews] review denied: [Bug 95258] Add support for blendmode to webkit rendering engine : [Attachment 161090] First try

[bugzilla-daemon at webkit.org]

Simon Fraser (smfr) <simon.fraser at apple.com> has denied Rik Cabanier
<cabanier at adobe.com>'s request for review:
Bug 95258: Add support for blendmode to webkit rendering engine
https://bugs.webkit.org/show_bug.cgi?id=95258

Attachment 161090: First try
https://bugs.webkit.org/attachment.cgi?id=161090&action=review

------- Additional Comments from Simon Fraser (smfr) <simon.fraser at apple.com>
View in context: https://bugs.webkit.org/attachment.cgi?id=161090&action=review


> Source/WebCore/ChangeLog:12
> +	   No new tests (OOPS!).

OOPS

This patch does change behavior: it makes compositing layers for blending, so
this should be tested.

> Source/WebCore/rendering/RenderInline.h:128
> +    virtual bool requiresLayer() const { return isInFlowPositioned() ||
isTransparent() || hasMask() || hasFilter() || hasBlendMode(); }

It might be worth making a method on RenderObject for hasMask() || hasFilter()
|| hasBlendMode(), since these all have similar effects.

> Source/WebCore/rendering/RenderLayerBacking.cpp:963
>  {
> -    return style->hasBorder() || style->hasBorderRadius() ||
style->hasOutline() || style->hasAppearance() || style->boxShadow() ||
style->hasFilter();
> +    return style->hasBorder() || style->hasBorderRadius() ||
style->hasOutline() || style->hasAppearance() || style->boxShadow() ||
style->hasFilter() || style->hasBlendMode();
>  }

I'm not sure this is correct. We use hasBoxDecorations() to tell if we need
backing store, but I don't think the blend mode needs to affect that answer.

> Source/WebCore/rendering/RenderLayerCompositor.cpp:1484
> +	   || renderer->hasBlendMode())

Again, not sure if this is true for all platforms. I don't think we need
backing store for CA to do blending.