POV-Ray : Newsgroups : povray.binaries.images : Star Trek inspired Starship - anim.png (1/4) : Re: Star Trek inspired Starship - anim.png (1/4) Server Time
12 Aug 2024 23:26:28 EDT (-0400)
  Re: Star Trek inspired Starship - anim.png (1/4)  
From: Hugo Asm
Date: 23 Jul 2003 14:50:15
Message: <3f1ed8e7@news.povray.org>
> I have to confess that I don't really understand UV.
> I'm not smart enough to pick up from context
> what it means.

I'd like to try and help you. I'm not an UV expert, to say the least. But I
know how it works:

Take any real-life object in your hand. Now, what do we learn about it?
Well, it has a surface. Lets say you want to apply a texture to that
surface. There are 2 ways to do it: 1) Take a pencil and begin to paint the
object. 2) Take a piece of paper, paint the paper, and glue that paper
around the object.

UV mapping is exactly like option 2. You paint on a piece of paper (the
coordinates of the paper is always <0,0,0> to <1,1,1>) and glue the paper
around the object. You can also cut up the paper in several pieces, to
better fit the object, just like you would probably do in real life. You can
even use the same pieces of the paper at several locations, by giving them
the same UV coordinates.

Usually UV coords are used in combination with meshes that consist of
triangles. As you know, each triangle has 3 corners that are positioned in
3D-space by 3 vectors. In POV-Ray (and many other programs) you can give
each of these vectors an additional information: A 2D coordinate, called an
UV. It only needs to be 2D because it refers to your texture, in other words
the piece of paper.. and the paper is flat.

This explanation hopefully covers the basics. If you want to become an UV
master you need practice of course. As do I... I certainly don't want to
discourage you from modelling with POV primitives in POV-Ray since they are
useful in many situations, they are fun, and not as hungry for memory.
Besides, your starship demonstrates that certain tools lead to certain
results. You are doing the job different that the people in Hollywood that
are using ... triangles, I suppose. That's why I said your starship looks
"older" than the Enterprise NX-01. It looks like it's been build by tools
that are "limited". That has a beauty, when done right (as your modelling
is).

However, if you decide you want to play with UV seriously, you need to
switch to meshes instead of primitives. Well, at least POV-Ray doesn't have
an efficient way of combining many primitives with UV coords.

If you have trouble with triangle-based applications, just as I always had
trouble with them, I suggest you try a freeware application that I've found:
Wings3d. It has a great user interface that is simple but efficient.
www.wings3d.com

Best regards,
Hugo


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