Requests are bad, I know... but I wanted to mention this anyway. Even if no
one wants to change it, I'd appreciate further explanation.

Section 6.7.12.6.5, "Mapping using warps," is pretty hard to understand, and
seems fairly short for covering the topic, IMO.

The section consists mainly of this, plus a syntax description and some
examples:

"With the cylindrical, spherical and toroidal warps you can wrap checkers,
bricks and other patterns around cylinders, spheres, toruses and other
objects. In essence, these warps use the same mapping as the image maps use.

"However it does 3D mapping and some concession had to be made on depth.
This is controllable by dist_exp (distance exponent). In the default of 0,
imagine a box <0,0> to <1,1> (actually it is <0,0>,
<dist^dist_exp,dist^dist_exp>) stretching to infinity along the orientation
vector. The warp takes its points from that box.

"For a sphere distance is distance from origin, cylinder is distance from
y-axis, torus is distance from major radius. (or distance is minor radius if
you prefer to look at it that way)"

OK, the part that I really think needs clarification is the second
paragraph. What does it mean to stretch a 2-Dimensional box "to infinity"
along a 3-Dimentional vector? I can't visualize it. And then, *how* does the
warp take it's points from that box? Each warp probably does it somewhat
differently.

Also, where does this "distance" keyword (mentioned in the third paragraph)
come from? Is it something that I specify, or is it taken into account when
selecting points from this mysterious box? Does it have something to do with
the words "dist^dist_exp" in the second paragraph?

I dunno... I just can't seem to understand this no matter how many times I
read it over. Even if no one wants to change the docs, it'd be cool if
someone offered me an explanation, just to clear it up. Thanks

- Slime
[ http://www.slimeland.com/ ]
[ http://www.slimeland.com/images/ ]

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