In article <390d4e69$1@news.povray.org>, "Simen Kvaal" 
<sim### [at] studentmatnatuiono> wrote:

> I saw your test images of the find_edges-filter. That one is very 
> useful, although what _I_ personally miss is the ability to make the 
> image look more like a wire-frame-model. I have developed an 
> algorithm (well... not actually... actually not at all...) that might 
> work: One takes the depth information and interprets that as a graph 
> of the two coordinate-axes, thus implying a function depth(x, y). The 
> natural place to put such a "wire-frame-line" would be where this 
> function have "breaks", kinda like discontinuities. (For example in 
> the intersection between two spherers.) 

Up to this point, it is very similar to the depth edge calculation 
method. I take the average difference in depth from the center pixel, 
and check for rapid, sharp changes in depth by marking pixels where the 
average difference is above a certain threshold. I do something similar 
for normals and colors.


> If one takes the gradient of depth(x, y) one obtains a 
> 2-vector-field, and taking the norm of that gives g(x, y). Taking the 
> norm og the gradient of that function, gives h(x, y). Where this h(x, 
> y) takes on very large values, we have a discontinuity in the image. 

You lost me here though...somewhere around "taking the norm of a 
2-vector-field". And something about taking the gradient of the gradient?


> Another post-process (or is it postprocess?): The ability to make a 
> r/b or g/r or whatever anaglyph for use with those 3d-glasses.

As someone else said, this would probably require separate images to be 
rendered. The color tinting could be done using color_matrix, and the 
images could be combined by using add and multiply with an image_map.
I think something that would be more interesting would be a random-dot 
stereogram, or "Magic Eye" stereogram. I have no idea how to do it 
though...

-- 
Christopher James Huff - Personal e-mail: chr### [at] yahoocom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://chrishuff.dhs.org/
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