Fabien Mosen wrote:
> 
> (now, the "but BMRT has shading language" argument is down :-))
Not quite: mr. Gritz has several times (1)emphasized the importance of
analytical antialiasing (which requires surface derivatives) and POVMan
doesn't support it. Yet.

______________________________________
1)he wrote in c.g.r.r:
===8<=8<========
This is really the crux of the issue.  Writing a simple compiler
and interpreter is not all that hard.  Writing a renderer that
has all the internals to support the fancy(*) parts of Shading
Language is nontrivial.

(*) By fancy, I mean features that aren't used in "plastic" or any of
the 14 naive required shaders listed in the RI spec, but which are
*mandatory* for absolutely any real-world shader.  Among other things,
these would include: derivatives, area operators, named coordinate
systems, (automatically) filtered texture lookups, automatically
interpolated user vertex variables (for reference meshes and such),
illuminance loops to allow custom local illumination models, and
message passing between different shader types (especially between
lights and surfaces).
===8<=8<========
Sigh, long way is ahead: my patch currently supports illuminance loops.
Derivatives and filtered texture lookups hopefully sometime in future...
Message passing in limited extent is probably also possible...

Post a reply to this message