CSS Light Sources

Probing for input and support for a possible native lighting specification.

This draft describes elliptical light sources that are not themselves
visible, but manifest in the form of interactions with other parts of the
CSS spec.

Light sources might be a desirable addition to the CSS Filters spec in
addition to/instead of a discreet property.

*Example Interactions with Existing Spec:*

   - Set text- and box-shadow to "auto" (or the lighting data type), and
   the assigned elements will respond to lighting sources on themselves or
   their parents.
   - Future bump map format for CSS and HTML images.
   - Interaction with CSS Shaders (esp. exposure facet).

*Properties (property: values; > default):*
*

lighting-origin
Point from which light is emitted.  2D coordinates behave like
background-position; 3D coordinates behave like translateZ.*

   - lighting-origin: lengthX lengthY lengthZ; > 0 0 0*
   *
   - lighting-origin-x
   - lighting-origin-y
   - lighting-origin-z

*lighting-target*
*Point toward which light is emitted.  If set to "omni" or equivalent to
the origin, light is omnidirectional.
*

   - lighting-target: [omni | lengthX lengthY lengthZ]; > omni
   - lighting-target-x
   - lighting-target-y
   - lighting-target-z

*lighting-radius*
*Two radii of the light source's ellipse of influence. Syntactical
facsimile of background-size.
*

   - lighting-radius: [cover | contain | lengthX lengthY]; > cover
   - lighting-radius-x
   - lighting-radius-y

*lighting-intensity*
*Overall opacity of lighting effect.
*

   - lighting-intensity: 0%-100%; > 50%

*lighting-exposure*
*Degree to which more brightly lit regions are saturated compared to less
brightly lit regions.
*

   - lighting-exposure: 0%-100%; > 50%

*lighting-color*
*Color of the light source.*

   - lighting-color: color; > white

*lighting-property*
*Light-able CSS properties influenced by source.  Reference against
transition-property.
*

   - lighting-property: [comma-delimited CSS properties | all]; > all

*Shorthand:*



lighting: origin, target, radius, intensity, exposure, color, property;



*Data Type:*



lighting(shorthand notation);



Looking forward to some people who are more expert in this area lending
their insights.  I've tried to keep this as CSS as possible while bringing
in some long-held features in the graphic design toolkit.


Cheers,

-Bri