[csswg-drafts] [cssom-view] Layout dimension that divides+rounds+sums to value greater than original dividend

BevanR has just created a new issue for https://github.com/w3c/csswg-drafts:

== [cssom-view] Layout dimension that divides+rounds+sums to value greater than original dividend ==
Is there any specification for HTML layout dimensions that divide, round and sum to a value greater than the original dividend?

For example;

- A container has two columns.
- Both columns are 50% the width of the parent.
- The width of the container is 9 pixels.
- How wide should each column be?

Major web browsers handle this differently;

Browser | First | Second | `element.offsetWidth` | Aliases †
------- | ----- | ------ | --------------------- | -------
Chrome | 5 | 4 | 5 and 4 respectively | No
Safari | 5 | 4 | 5, _even for the 4px column_ | No
Firefox | 4.5 | 4.5 | rounded to 5 | Yes
Edge | 4.5 | 4.5 | rounded to 5 | Yes
 
† Allows element boundaries to be mid-pixel, causing that pixel to be aliased based on the two elements that it straddles.

Test cases;

- [Column width](https://bevanr.github.io/5-and-5-is-9/width.html)
- [Row height](https://bevanr.github.io/5-and-5-is-9/height.html)

The specification for [`offsetWidth`](https://drafts.csswg.org/cssom-view/#dom-htmlelement-offsetwidth) only says that offsetWidth must be an integer.  Is this specified elsewhere?  Should it be?

Is this the correct place to discuss?

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/1211 using your GitHub account

Received on Thursday, 13 April 2017 02:14:53 UTC