- From: Dirk Schulze <dschulze@adobe.com>
- Date: Tue, 15 Oct 2013 10:37:18 -0700
- To: Chris Lilley <chris@w3.org>
- CC: FX <public-fx@w3.org>
On Oct 15, 2013, at 6:02 PM, Chris Lilley <chris@w3.org> wrote: > Hello , > > > Here is a proposal for a new feHSL element which performs hue rotation > and saturation changes without suffering from internal clipping. Due > to filter effects clipping after each primitive, saturation increases > will still suffer from clipping in a multi-stage pipeline. > > I didn't provide for any operations on the L axis of HSL because > operations on lightness or luminance are already available by other > means. > I wonder how the proposal solves the problem. The input is still RGB, the output is still RGB. It might differ between linearRGB or sRGB. So you still have the clipping, no? Could you elaborate more please? Also, would the new element ignore the color-interpolation-filters property? Greetings, Dirk > ================================================= > > Name: feHSL > Categories: Filter primitive element > Content model: Any number of the following elements, in any order: > > <animate> > <set> > > Attributes: > > core attributes — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’ > presentation attributes — ‘alignment-baseline’, ‘baseline-shift’, > ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, > ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, > ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, > ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, > ‘flood-color’, ‘flood-opacity’, ‘font’, ‘font-family’, ‘font-size’, > ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, > ‘font-weight’, ‘glyph-orientation-horizontal’, > ‘glyph-orientation-vertical’, ‘image-rendering’, ‘isolation’, > ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker’, > ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘mix-blend-mode’, > ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, > ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, > ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, > ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, > ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, > ‘word-spacing’, ‘writing-mode’ > filter primitive attributes — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’ > ‘class’ > ‘style’ > ‘in’ > ‘type’ > ‘value’ > > DOM Interfaces: SVGFEHSLElement > > This filter applies a transformation in HSL colorspace. Input values > are converted (if needed) from the colorspace given by > 'color-interpolation-filters' to sRGB, and then to HSL for processing. > Results are converted from HSL to the colorspace given by > 'color-interpolation-filters'. > > The calculations are performed on non-premultiplied color values. > > Attribute definitions: > > type = "hue" | "saturation" > Indicates the type of operation to be performed: hue rotation or > saturation/desaturation. The lacuna value for 'type' is "hue". > > value = <number> > For type="hue", the value represents a hue rotation in degrees. > Positive and negative angles may be specified. The new hue angle H' > is given by > > H' = (H + value) mod 360 > > For type="saturation", the value represents a saturation multiplier. > Values less than 1.0 represent desaturation; values greater than 1.0 > represent increases in saturation. A value of 0.0 results in full > desaturation to the L axis. The new saturation value S' is given by > > S' = S * value > > Note that results are clamped to the saturation range 0.0 ... 1.0 > > The lacuna value of 'value' depends on the value for 'type'. For > type="hue" the lacuna value for 'value' is 0.0 (no rotation); for > type="saturation" the lacuna value for 'value' is 1.0 (no change in > saturation). > > ============================================================= > > Add an example or two and some suitable definition for the DOM > interface. > > -- > Best regards, > Chris mailto:chris@w3.org > >
Received on Tuesday, 15 October 2013 17:37:46 UTC