Bug 198998 – [CoordinatedGraphics] support bounds origin

• Component: WebKitGTK
• Status: RESOLVED FIXED

[Philippe Normand]

It seems that now, only fixed elements of the page scroll. The others remain stuck, I'll attach a screenshot.

[Philippe Normand]

Created attachment 372458 [details]
screenshot

The header bar moves when scrolling (it should remain fixed on top of the page) while the rest of the page doesn't move (it should)

[Philippe Normand]

Simon, would you have any hint? Reverting your patch fixes the regression.

[Simon Fraser (smfr)]

Have GTK take GraphicsLayer boundsOrigin into account when positioning descendant layers.

[Zan Dobersek]

Created attachment 372478 [details]
WIP

[Simon Fraser (smfr)]

Comment on attachment 372478 [details]
WIP

View in context: https://bugs.webkit.org/attachment.cgi?id=372478&action=review

> Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:919
> -        layerState.mainBackingStore->invalidate({ { }, IntSize { m_size } });
> +        layerState.mainBackingStore->invalidate({ IntPoint { m_boundsOrigin }, IntSize { m_size } });

Invalidation always needs to round out (expand). So enclosingIntRect()

> Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:926
> +        layerState.mainBackingStore->createTilesIfNeeded(transformedVisibleRect(), IntRect(m_boundsOrigin.x(), m_boundsOrigin.y(), m_size.width(), m_size.height()));

enclosingIntRect()?

[Carlos Garcia Campos]

Is this GTK specific? Or coordinated graphics? isn't WPE affected?

[Zan Dobersek]

Comment on attachment 372478 [details]
WIP

View in context: https://bugs.webkit.org/attachment.cgi?id=372478&action=review

>> Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:919
>> +        layerState.mainBackingStore->invalidate({ IntPoint { m_boundsOrigin }, IntSize { m_size } });
> 
> Invalidation always needs to round out (expand). So enclosingIntRect()

This actually has to go unchanged as it relates to the content rectangle, not the layer one.

>> Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:926
>> +        layerState.mainBackingStore->createTilesIfNeeded(transformedVisibleRect(), IntRect(m_boundsOrigin.x(), m_boundsOrigin.y(), m_size.width(), m_size.height()));
> 
> enclosingIntRect()?

Same here.

> Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:1112
> -    m_layerTransform.setPosition(m_adjustedPosition);
> +    m_layerTransform.setPosition({ m_adjustedPosition.x() - m_boundsOrigin.x(), m_adjustedPosition.y() - m_boundsOrigin.y() });

Main requirement is to have the bounds origin properly complement the position value. This was a good start, but further changes are needed in computePixelAlignment().

[Zan Dobersek]

Created attachment 372548 [details]
WIP

[Adrian Perez]

(In reply to Zan Dobersek from comment #8)
> Created attachment 372548 [details]
> WIP

I have tried this patch locally and so far the few websites
that I tested so far (e.g. GitHub, Twitter igalia.com) are
working well \o/

[Simon Fraser (smfr)]

I reverted most of the change that caused this, so page scrolling on trunk is probably OK again. If GTK ever wants accelerated overflow scroll, then it will need this patch.

[Alice Mikhaylenko]

I don't know if it's related, but kinetic scrolling is broken in trunk. It jumps up a bit instead of triggering kinetic scrolling.

[Zan Dobersek]

Repurposing.

[Zan Dobersek]

Created attachment 379633 [details]
Patch

[Zan Dobersek]

Comment on attachment 379633 [details]
Patch

Clearing flags on attachment: 379633

Committed r250418: <https://trac.webkit.org/changeset/250418>

[Zan Dobersek]

All reviewed patches have been landed.  Closing bug.