- From: Amelia Bellamy-Royds via GitHub <sysbot+gh@w3.org>
- Date: Tue, 18 Sep 2018 01:08:16 +0000
- To: public-svg-issues@w3.org
Looking closer at the section on clamping values, I think this should either be dropped completely or significantly rewritten. Rules about clamping color component values and opacity values are now defined in CSS Color. (And, quite frankly, the SVG 1 wording isn't very clear to start with, relying on vague phrases like "at the time which opacity values have to be processed".) Most other properties where clamping is relevant should have the clamping behavior defined as part of the property definition. For now, I'll probably leave in a one-paragraph general rule: "Where not otherwise specified…" clamping should happen as late as possible. That way, there is no normative change in case of any properties or attributes which _don't_ have their own detailed rules. _____________________________ For reference, the existing text is as follows: <h2 id="RangeClamping">Clamping values which are restricted to a particular range</h2> <p>Some numeric attribute and property values have restricted ranges, such as color component values. When out-of-range values are provided, the user agent shall defer any error checking until after presentation time, as composited actions might produce intermediate values which are out-of-range but final values which are within range.</p> <p>Color values are not in error if they are out-of-range, even if final computations produce an out-of-range color value at presentation time. It is recommended that user agents clamp color values to the nearest color value (possibly determined by simple clipping) which the system can process as late as possible (e.g., presentation time), although it is acceptable for user agents to clamp color values as early as parse time. Thus, implementation dependencies might preclude consistent behavior across different systems when out-of-range color values are used.</p> <p>Opacity values out-of-range are not in error and should be clamped to the range 0 to 1 at the time which opacity values have to be processed (e.g., at presentation time or when it is necessary to perform intermediate filter effect calculations).</p> -- GitHub Notification of comment by AmeliaBR Please view or discuss this issue at https://github.com/w3c/svgwg/issues/520#issuecomment-422219897 using your GitHub account
Received on Tuesday, 18 September 2018 01:08:18 UTC