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Antialiasing is done iquite differently in the ray tracer and the scanline renderers.

The scanline renderer always uses a 4x4 grid of samples per pixel with all the samples in 4 rows and 4 columns.  This is why it's so fast - many of the computations are done once per image instead of per pixel or per sample.  But even samples are very bad for soft shadows.  So for soft shadows multiple shadow samples are takes for each image sample.  First a few samples are taken.  If any of them are different (i.e. one is in a shadow and one is not) then that pixel and the neighboring ones are samples a higher number of times.  This allows a high number of samples to be used on shadow edges and fewer in areas that they aren't needed because they're all the same.

The ray tracer uses just one shadow sample per image sample.  But because each sample is independently traced a better distribution can be done.  Multijitrered is a very good method - much better than random or Monte Carlo.  Likewise glossy surfaces trace just one sample per pixel.  That's why non-aa glossy surfaces are so speckled.  Over all it's best to do it this way because you sample all the varying parameters evenly.  The scanline renderer samples shadows at a much higher rate that it does the image - but that's required due to very thing that makes scanline do fast - the regularly spaced image samples.

So you will not be able to exactly match scanline images with ray traced for this an a dozen other reasons.

You're right.  There is no near and far Z with ray tracing.  There is no need for it becuase thereisn't a perspective projection, so no divide and all of it's related precision problems.  Everything is done in world coordinates.

blanc - no, you can't combine materials - yet.  I  plan to add more materials and options to both the scanline renderer and to the ray tracer.  One possibility is to add more complex operateor - like a blend option that would aallow you to combine two or more materials.  Another is to allow various components like the specular hilight to be a general material.  There ar some major design issues I have to work out first including how to present this to users.  Attributes are quite flexible but not very easy to use ao I'd like another technique.

CobraSpectre - No colored shadows yet either but they are in the works.  Caustics are much harder to do (and can take a LOT more time) so I don't think I'll get to them anytime soon.

There ther's the current rendering time.  I haven't done much to speed it up yet.  I hope to be able to at least halve the time for a typical render.

What specifically are you trying to do?

Not all raytracing materials support all textures.  The dielectric and transparent classes only support alpha channel textures but even that is not a physically realistic.  That would require 3D textures.  Other properties like diffuse color don't make any sense in those classes since they are surface properties and can't be integrated throughout the material like the solid diffuse color can.

The glossyreflector class doesn't support diffuse textures but it should because that class only needs surface properties.

The base Anim8or class should support all textures, however.

Just to peak your interest, here's an example of just one new thing you can do with it:



Be the first on your block to get a copy!

I have posted a new preview, v0.97.  It's main feature is a ray tracer called ART (for Anim8or Ray Tracer, naturally!)  Check out the "v0.97 Preview" link in the menu or just click here: http://www.anim8or.com/download/preview/index.html  Don't miss the ray tracer documentation either:  http://www.anim8or.com/download/preview/art_raytracer.html

Here's an example of just one new thing you can do with it:

You also might get things to improve by upgrading your graphics driver.  There are many little bugs in pretty much all Vista graphics drivers for OpenGL but they are continually being fixed.

Anim8or just calls the standard file save dialog function in Windows.  It has a "*.an8" filter by default and an option to choose "*.*".  I would think that Vista would behave the same as Windows in this respect.  I'll try it on a Vista computer to see if I can see something.