1338393 - Filter: have the coordinates in the FilterDescription be independent of the filter resolution

Status: NEW

(Core :: Web Painting, defect)

Description

[u459114]

Bug 1287492 comment 26
mstange said:
It would be really nice to have the coordinates in the FilterDescription be independent of the filter resolution (for example in float user space pixels) and then convert to actual pixels only during painting, when we create FilterNodes from the FilterDescription (in FilterSupport). At that point we'd be able to look at the DrawTarget to know what resolution we should use for the intermediate surfaces and the FilterNode coordinate attributes.

Comment 1

[u459114]

1.
nsSVGFilterInstance::nsSVGFilterInstance(const nsStyleFilter& aFilter,
                                         nsIFrame* aTargetFrame,
                                         nsIContent* aTargetContent,
                                         const UserSpaceMetrics& aMetrics,
                                         const gfxRect& aTargetBBox,
                                         const gfxSize& aUserSpaceToFilterSpaceScale,
                                         const gfxSize& aFilterSpaceToUserSpaceScale)
Remove the last two scale vectors. How about aMetrics?

2. 
nsCSSFilterInstance cssFilterInstance(aFilter, shadowFallbackColor,
                                        mTargetBounds,
                                        mFrameSpaceInCSSPxToFilterSpaceTransform)
Remove the last parameter.

Comment 2

[u459114]

Attachment: Bug 1338393 - Part 1. Remove nsSVGFilterInstance::mUserSpaceBounds.

mUserSpaceBounds is not used at all. Remove it and all calculation relative to
it.

Review commit: https://reviewboard.mozilla.org/r/112074/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/112074/

Comment 3

[u459114]

1. All attributes store in FilterPrimitiveDescription need to be float type. 
2. All attributes store in FilterPrimitiveDescription need to be in user-space(not filter space)
3. FilterPrimitiveDescription::PrimitiveSubregion should return Rect, instead of IntRect. Subregion should be in user space, not filter space
4. FilterPrimitiveDescription::FilterSpaceBounds should be rename as UserSpaceBounds and return Rect instead
5. FilterPrimitiveDescription generators(nsSVGFilterInstance/nsCSSFilterInstance) should not bring userspace-to-filterspace scale vectors into FilterPrimitiveDescription.
6. FilterSupport is in charge of convert user-space attributes in FilterPrimitiveDescription to filter-space attributes in FilterNodes.