On Wed, 11 May 2005 21:26:33 +0200, Tim Nikias  

<JUSTTHELOWERCASE:timISNOTnikias(at)gmx.netWARE> wrote:

>> I think he means using mipmaps, and then taking the two nearest mipma
ps
> for
>> the scale level of the current sample, bilinearly interpolating to ge
t  

>> the
>> color for each of them at the sample position, and then linearly
>> interpolating between the two results to get the final value.
>>
>> In my experience, this approach generates a little too much blurring,
  

>> and
>> when I program with OpenGL, I often wish that I could have nice
>> anti-aliasing instead.
>
> As I just recently learned in a course at my university, the way you
> describe it is the standard hardcoded way on older graphics cards. The
  

> new
> ones (ATI Radeon 9800 and upwards, and I think the NVidias FX and  

> upwards)
> come with programmable Vertex and Fragment Shaders, and with fragment
> shaders you can script some more elaborate way of interpolation. The g
uy
> showed us some examples of the usual mipmap-fading to avoid jumps betw
een
> the different mipmaps, and one which interpolates amongst several
> mipmap-levels, depending on the angle of the pixel (and thus the area 
it
> would cover on the image-map). It looked real crisp.

That way i was hoping to go with povray as well. To program the texture 
(or
pigment) stage to support different blending mode for example. But it is

another topic :) It's possible, but not like my mind is winded. So i hav
e
to rethink some stuff.

> However, we're drifting away from the topic at hand, being of help to 
 

> tahoma
> to get his images look good. :-)

I hope to get them look good when trying different antialiasing settings
.
More i cannot gain from this thread (mipmapping is not supported and
maybe useless). Adjusting materials is on the one hand an artist task an
d
on the other hand one of the translater from OpenGL materials to povray
one's.

But what i also get is, offline rendering (raytracing) does not really
differ from realtime rendering that much. The concepts are almost the sa
me,
the community is a little different :)

Thanks for you help

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