Re: Re: [opendx-users] Volume rendering tutorial problems

[Gregory D Abram]

OpenGL's   3-D texture mapping can be used to do some fantastic volume
rendering, though is limited to regular grids.  There's also been some
great work at Stanford, at least, to put the application of the transfer
function down on the card so that you can change it in real time.

I would *love* to see this sort of capability added to OpenDX.  I think it
would be fairly straightforward to add as a special-purpose volume-only
renderer.

Greg



                                                                                
                                                 
                      David Thompson                                            
                                                 
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                      [EMAIL PROTECTED]        Subject:  Re: Re: [opendx-users] 
Volume rendering tutorial problems   
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                      06/13/2003 03:59 PM                                       
                                                 
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The difference is in the rendering algorithms. Just like Rayshading
is much better than anything that dx can produce; the Phaung shading
in software rendering is much better than the shading in OpenGL.
Also, OpenGL does not support a volume rendering option (thus the
limitations you're seeing). It is possible to simulate volume
rendering by using an opacity map on the solid volumes with hardware,
but that is the best you can do.

David

>  > Make sure to try software rendering. Hardware does not support volume
>>  rendering.
>>
>>  David
>
>Oooo... Pretty! But, why doesn't volume rendering work in hardware
>mode? I have noticed that some pictures just look better in software
>than in hardware mode (less gleam, better gradual change of hues and
>colours), does this have anything to do with it?
>
>Maarten


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David L. Thompson                   Visualization and Imagery Solutions,
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