[css-masking] 'mask: none' clear all masking operations

Hi,

During the WG meeting today, there was a question if 'mask: none;' can clear all masking operations on an element.

As an introduction, the CSS Masking spec defines three main properties: mask, mask-box-image and clip-path where some are shorthands for a couple of longhand properties:

mask
    * mask-image, mask-source-type, mask-repeat, mask-position, mask-clip, mask-size

mask-box-image:
    * mask-box-image-source, mask-box-image-slice, mask-box-image-width, mask-box-image-outset, mask-box-image-repeat

While the 'mask*' properties are similar to the 'background*' properties,
the 'mask-box-image*' properties are similar to the 'border-image*' properties.

Since 'mask' and 'mask-box-image' are two shorthands, it seems to be impossible to disable all masking operations with 'mask: none'. The biggest problem is that the initial value for 'mask-image' is 'none' and therefore would always disable 'mask-box-image' as well.

I added a note to the 'mask' property, that 'mask: none' will just disable masking by the 'mask*' properties, but not for 'mask-box-image*' properties. If there are no objections, I will remove the issue 1 (Shall ‘mask: none’ influence ‘mask-box-image’? This would mean to "link" the both shorthand properties.) that I added to investigate into this raised concern.

Greetings,
Dirk

Received on Thursday, 30 May 2013 01:01:33 UTC