POV-Ray : Newsgroups : povray.off-topic : Geometric puzzle : Re: Geometric puzzle Server Time
5 Sep 2024 11:26:21 EDT (-0400)
  Re: Geometric puzzle  
From: Invisible
Date: 17 Dec 2009 10:19:26
Message: <4b2a4bfe$1@news.povray.org>
>> Looking around the room I'm sitting in now, most if not all items in 
>> it would be far, far easier to create with POV-Ray.
> 
> I beg to differ.

Well, it was written by *me* I guess...

>> Man-made objects tend to be particularly easy to construct using CSG. 
>> My telephone, for example. Throw a few cubes and prisms together with 
>> a little CSG and it's done.
> 
> But it's going to look like 80's CGI because you can't do rounded edges 

Or, more correctly, you can't do rounded edges with triangles. You can 
only take jaggid geometry and smother it with trickery until it gives 
the vague suggestion of roundness.

If I want a round button on my phone, just select a cylinder and it's 
done. You could also CSG a cone onto the end for a bevel, or use a torus 
for a smooth bevel. Piece of cake.

> And you're stuck with 
> perfectly cylindrical rounds, IRL they are not usually used on edges 
> because of the discontinuity in curvature (it doesn't give smooth 
> reflections).

...it doesn't?

> Maybe your phone is different, but my phone looks impossibly hard to do 
> in POV SDL with all those complex curved surfaces and rounded edges.

My phone is pretty squarish, with square and round buttons. Looks quite 
easy to do. The coilled cable might be difficult, what with POV not 
having real splining tools. (You gotta type in the coordinates by hand.) 
About the only remotely tricky part would be the handset.

>> A brick with a rough surface is almost a 1-liner in 
>> POV-Ray, but would be ludicrously hard to model with billions of 
>> triangles. (You'd have to fake it with devious texture mapping.)
> 
> Or apply a noise texture to the displace modifier if your scene calls 
> for a brick with real geometry.

...wuh?

> BTW what's your 1-line for a rough brick in POV?  How long did it take 
> you to write?

You take the equation for a plane, add some noise to it. OK, for a brick 
I guess you'd need a seperate isosurface for each side. Still much 
easier than trying to model roughness by hand.


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