> Sorry but i simply don't get it.  Your original motivation for considering
> implementing scanline rendering in POV-Ray is to allow something that is
> not possible in POV-Ray as you state (i.e. efficient rendering of scenes
> with many objects).  But now you write you will only support a subset of
> those shapes already available in POV-Ray - how does this fit together?

Sorry for the confusion. For my purposes,
I don't require all primitives, at least in
the short to mid-term. Further along, it
would be desirable to have as many POV
primitives supported as possible. I need
the "lots of shapes" capability to implement
shaders, and most of the time they get
by with simple primitives like triangles,
boxes, spheres, etc. This is natural since
the shapes tend to occupy a fairly small
number of screen pixels when projected.
For shapes like hair strands and grass blades,
however, supporting a spline (rope?) primitive
should be done.


> I think this whole thread suffers from one serious problem - You never
> made a clear and open statement of your objectives and you don't seem to
> be willing to discuss whether your idea for a solution (i.e. scanline
> rendering) will meet your objectives.  All people who replied to you in
> this thread have a good deal of experience with POV-Ray in various fields
> but i have the impression that you either ignore or don't understand most
> of the arguments we have given.

I'm pretty sure I stated I was open to
any ideas to meet the goal, but I admit
there was some sidetracking into that
talk with Mr. Froehlich about the
merits of scanline vs. raytracing.
I should have tried harder to stay on course.

Your isosurface pictures are neat. I don't
know if I mentioned that my pic was antialiased
(over a million sampled screen pixels)
and done on a 633Mhz Celeron. But regardless
of how close in performance the two are,
I'm not much of an isosurface designer.
I also don't see how an isosurface would
be able to plant lots of trees or independant
rocks on the terrain and maintain the
same memory/rendering performance. If I
was limited to raytracing, I would definitely
brush up on isosurfaces, but otherwise...

Like I mentioned, I think I have to try
a prototype scanline implementation in POV to
see how it goes. The jury is kind of out
on conclusions just yet, and I don't
want to endorse anything until I have
accurate benchmarks. By Mr. Froehlich's
own admission, raytracing speed doesn't
compete with scanlining until you have
billions of objects, so there's definitely
room for exploration under that limit.

Ray

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