POV-Ray : Newsgroups : povray.general : Feature Request - subdivision surfaces + normal displacement Server Time
31 Jul 2024 16:18:33 EDT (-0400)
  Feature Request - subdivision surfaces + normal displacement (Message 1 to 2 of 2)  
From: Samuel Benge
Subject: Feature Request - subdivision surfaces + normal displacement
Date: 24 Oct 2006 19:05:25
Message: <453e9c35$1@news.povray.org>
Now is probably the best time to ask this....

Will the official version of POV-Ray ever support subdivision surfaces? 
You could base it on POV-Sub (http://www.cise.ufl.edu/~xwu/Pov-Sub/).

Parsing with POV-Sub is very quick, and you can save disk space by 
keeping your meshes small. This patch also allows you to smooth a mesh 
automatically, which is something many people would love to be able to 
do without having to use a patch.

Now if normal displacement could be added to the patch, the combo would 
be very powerful. There could be three options for displacement: before 
subdivision, after subdivision, and at each substep.

Option three could have a float value for the amount of displacement on 
each substep.... for instance, 0.5 would cause 50% displacement on the 
first step, 25% on the next, and 12.5% on the next, and so forth. Each 
substep would be displaced on the current surface normal, so you could 
get complex effects not available with other subpatch systems.

Here's how it might look:

mesh{
  subdivision{
   method 3, 0.5
   substeps 3
   displacement{
    bozo
    displacement_map{
     [0 rgb 0]
     [1 crackle]
    }
   }
  }
}

Implementing this would make another useful modeling technique available 
to the POV-Ray community. It would allow a person to make complex 
objects from a simple cube or spherical mesh. Simple meshes could even 
be distributed for this purpose.

~Sam


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From: Warp
Subject: Re: Feature Request - subdivision surfaces + normal displacement
Date: 24 Oct 2006 19:16:28
Message: <453e9ecc@news.povray.org>
Well, you could use the pcm format, read it into arrays and use the
surface subdivision suite:

http://www.geocities.com/evilsnack/nsss.htm

  To convert regular meshes into pcm you can use the program at:

http://www.geocities.com/ccolefax/pcm.html

and to read it use the macros in the same site.

  For mesh2 you'll have to use an improved version of the program
(currently Windows-only) at:

http://warp.povusers.org/WinMeshcomp30_beta3.zip

but you'll have to write the reading code yourself. Shouldn't be too
difficult, though.

-- 
                                                          - Warp


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