[css-masking] Minor comments on Mask Rendering Model

https://dvcs.w3.org/hg/FXTF/raw-file/tip/masking/index.html#the-mask-rendering-model

   # The application of the ‘clip-path’, ‘mask’ or ‘mask-image’ properties
   # to an element formatted with the CSS box model establishes a stacking
   # context in the same way that CSS ‘opacity’ does

Append a reference to CSS3 Color here.

   # The ‘mask’ and ‘mask-image’ properties have no effect on the geometry
   # of any element's CSS boxes.

This seems to imply that 'clip-path' does have an effect on their geometry.
Is that true?

Also 'mask-box-image' isn't mentioned in this section. Should it be?

This section is a little messy thematically. I would group the sentence
about hit-testing with the one about geometry, and the one about
compositing with the one about stacking contexts.

https://dvcs.w3.org/hg/FXTF/raw-file/tip/masking/index.html#layering
5.1 Layering Multiple Mask Images

This should probably be part of 6, Mask, not up in this section, which seems
to be general to all the features in the spec.

# The first layer is the layer closest to the user, the next one is painted
# behind the first, and so on.

Does the ordering actually make a difference for masks? If not, maybe
this paragraph isn't needed.

5.2. Calculating mask values
https://dvcs.w3.org/hg/FXTF/raw-file/tip/masking/index.html#MaskValues

The title is rather cryptic to me, who doesn't study graphics operations.
Maybe "Mask Interpretation"? It should mention the 'mask-source-type'
and 'mask-type' properties and how they affect this interpretation.

I would put a <dl> in here, and define "alpha mask" and "luminance mask"
or somesuch, partly to create a referenceable definition but mostly
because that will help make this section easier to grok.

~fantasai

Received on Tuesday, 2 April 2013 01:08:03 UTC