[CSSWG] Minutes Seattle F2F Wed 2014-01-29 PM IV: Custom Filters, SVG Hover Effects

Custom Filters
--------------

   RESOLVED: take custom shaders out in a week, unless somebody objects
             before that.

SVG Hover Effects
-----------------

   CSSWG and SVGWG discussed translating some common hover effects from
   CSS to SVG, and the problems thereof.

====== Full minutes below ======

Custom filters removed?
-----------------------

   krit: Agenda request: filter effects and custom filters.
   <krit> http://dev.w3.org/fxtf/filters/
   krit: We had to limit them already because of security.
   krit: And they don't have the expected power.
   krit: Current impls have problems with them.
   krit: Especially with combined custom and standard filters.
   krit: (Not all impls.)
   krit: We still believe in filter effects, but custom filters isn't
         the right solution.
   Simon: We removed them in webkit, so support the removal.

   krit: New feature would not use shaders.
   ChrisL: Seems slightly sad since Microsoft added webGL support.
   ChrisL: But if two impls removed them already...
   krit: No impls currently remaining.
   Rossen: What was this again?
   krit: Pixel manipulation with WebGL
   heycam: Plan for replacement?
   krit: Looking for more use cases, providing hit testing effects.
   krit: Hit testing was a problem with current solution.
   heycam: So no future for generic shader-like thing?
   krit: Many users were relying on pixel shaders, but they were security
         threat, so we had to limit them already.
   krit: Couldn't actually look at color value.
   krit: We want to come up with a proposal, and want feedback.
   krit: More focus on use case of CSS.

   heycam: A bit afraid to get a 100 different canned effects...
   florian: What is the proposal?
   krit: Not in presentable shape yet.
   Rossen: Can we remove after seeing the new proposal?
   sgalineau: But it is holding up the spec.
   ChrisL: Are you asking to defer removal a bit?
   sgalineau: The feature will go away, so what do we get by keeping it
              in a bit longer?
   krit: I'm more focusing on SVG filters at the moment, and bringing
         that to LC.
   <sgalineau> the feature would end up at risk so not sure what the value
               of keeping it around
   plinss: So take out? move to future level?
   krit: Other impls might take it up again.
   Rossen: Like to defer decision by a week.
   krit: OK with me.
   sgalineau: What do we get in a week?
   RESOLVED: take custom shaders out in a week, unless somebody objects
             before that.

Hover Effects in SVG
--------------------

   Topic: backgrounds and colors and outlines in SVG
   shepazu: Sometimes want to use outlines and colors, e.g., on hover.
   shepazu: SVG doesn't have on-hover effect on it sown.
   shepazu: Have to find the bounding box yourself.
   shepazu: These effects do no affect flow.
   krit: :hover is supported.
   ChrisL: What spec?
   krit: it is automatic.
   shepazu: Is this a terrible idea?
   shepazu: Would we allow whole background thing, or just color?
   shepazu: Fill area would be bounding box of element.
   shepazu: Use case is hover.

   krit: Why not add an element behind it?
   shepazu: Kind of a pain. I've done it.
   shepazu: Keep track of transforms, etc, yourself.
   shepazu: It is not perfect, but it is a start.
   shepazu: Could add stroke effects to the outline also, vector effects.
   shepazu: But simple thing now, and rest for future.

   heycam: [showing something]
   heycam: Approaches in the past included filters, and filling bounding
           box with color. Bit of a hack.
   shepazu: I prefer "on hover, background = white"
   krit: Sceptical about background. Don't see use case.
   krit: Don't think this is what you really want to have.
   krit: Consider a complex shape, rectangle behind it is not what you want.

   smfr: repeated images with fill?
   krit: Yes, just decided today :-)
   shepazu: I suggested things that don't change reflow.
   [discussion of what it should look like for different shapes]
   shepazu: SVG often used for icons.
   krit: Icons don't have hover.
   simonf: Often element behind the icon has the hover.
   krit: Outline for accessibility.

   shepazu: I'd like to find out the concerns of the CSS WG with this.
   [CSS WG has no opinion]

   ChrisL: More consensus on outline than on backgrounds.
   florian: CSS doesn't have definition of where outline goes, does it?
   dbaron: Correct. I have thought about it, but not finished.
   florian: I remember something about 3d transforms making outline harder.
   krit: Outline gets smaller when object is smaller because of clip path,
         but we decided recently that outline should actually be clipped.
   <ed> svg tiny 1.2 has viewport-fill and viewport-fill-opacity properties
        that are similar to what shepazu is asking for with bg, though
        more limited in which elements they apply to

   heycam: Does CSS define outline is outside the box?
   dbaron: We have or had an outline-offset.
   florian: I think we have neither a definition nor interop.
   leif: Significant latitude for impls.
   ChrisL: That was certainly so with the orig definition.
   leif: Not even defined if it is on top of everything, or only on top
         of the element
   leif: But outline-offset is not problematic, but don't know about interop.

Meeting closed.
<RRSAgent> http://www.w3.org/2014/01/30-css-minutes.html

Received on Thursday, 20 February 2014 00:21:36 UTC