🚀 go-pugleaf

> I am not new to programming, but I am fairly new to graphics.  I have a
> few terminology questions.

Yeah, these terms need to be made clear in the FAQ.

> I understand what texture mapping is.  What exactaly is perspective
> mapping?  And how does it differ from texture mapping?

My definitions:

Texture mapping:  Mapping a 2D object onto a 3D object...say, mapping
                  a picture of the world (flat) onto a globe.  Even
                  this goes a bit beyond texture mapping.  Map a 2D
                  image onto a bunch of polygons, for instance.
Perspective mapping:
   Take a 2D graphics image, and map it sloping on an angle as in
   old 3D games like Pool of Radiance.

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Kind of like that.  The original object would have been a flat rectangle, but
it was scaled to fit inside that pattern.

> Also, earlier on this thread, someone mentioned the "blindingly obvious
> fact" (not to little ole me) that wolfenstein 3d was done with "scaled
> pixel collumns" or something like that.  Will someone please elucidate?

No, it's not blindingly obvious.  The best I can come up with on this one (I
think is was Dave who wrote it):  If you look at my scaling routine, I think
you'll see.  If not, he probably meant that certain rows or columns would
become duplicated several times or deleted from the image.

> also, while I know assembler, I would find a posting of the
> aformentioned (previous response) psuedo-code and then to attempt to
> write my own assembler implementation, as I truly believe the best way
> to truly learn and understand an algorithm is to sucesfully program it.
> (although it is much easier to do this if you understand it first :))

I wish I hadn't lost that pseudo-code.  I'm going to be leaving for Denver
soon, and after I get back on the 16th, I'll rewrite it.  Right now, there
is a lot of hustle and bustle to get prepared.

Josh