[comp.graphics] just a random idea

seth@miro.Berkeley.EDU (Seth Teller) (12/04/88)

I have this idea, see: you take an image (like any bunch of pixels, could even
be a picture) and you kind of paste it on a surface, like wallpaper on a wall.
This way you could make the dullest of polygons look interesting. Like you
could take a Playmate, or a monkey, or something, and put it on a coffee-pot
(well, maybe a coffee-pot is too hard, I'll think of something else).
Waddaya say?

[ this random idea actually due to my fractal-head pal Alain Fourier ]

	bye for now!!

	-- seth     seth@miro.berkeley.edu

foo@titan.rice.edu (Mark Hall) (12/04/88)

In article <7980@pasteur.Berkeley.EDU> seth@miro.Berkeley.EDU (Seth Teller) writes:
>I have this idea, see: you take an image (like any bunch of pixels, could even
>be a picture) and you kind of paste it on a surface, like wallpaper on a wall.
>This way you could make the dullest of polygons look interesting. Like you
>could take a Playmate, or a monkey, or something, and put it on a coffee-pot
>(well, maybe a coffee-pot is too hard, I'll think of something else).
>Waddaya say?
>
>	-- seth     seth@miro.berkeley.edu


   I'd say you have reinvented texture mapping. The original idea 
 was to create more realistic surfaces than those representable
 by polygons and bicubic patches. You mapped a texture onto the 
 surface to simulate real surfaces which have non-planar texture. 
 The "texture" can be surface normals, color info, really anything
 you want, even Playmates.

   I think the first reference to this was Ed Catmull's PhD thesis, 
 "A Subdivision Algorithm for Computer Display of Curved Surfaces"
 University of Utah (1974). You can get a copy of most any thesis 
 by going to your local library. They will have info on where to order
 the thesis from. 

   Many textbooks talk about texture mapping. My old version of Foley 
 and VanDam has a paragraph on it. The reference to Ed Catmull's thesis
 I got from "Procedural Elements for Computer Graphics" by David Rogers.
 Rogers spends about 8 pages on texture mapping.

 - mark

u-jmolse%sunset.utah.edu@wasatch.UUCP (John M. Olsen) (12/04/88)

seth@miro.Berkeley.EDU (Seth Teller) writes:
|I have this idea, see: you take an image (like any bunch of pixels, could even
|be a picture) and you kind of paste it on a surface, like wallpaper on a wall.
|This way you could make the dullest of polygons look interesting. Like you
|could take a Playmate, or a monkey, or something, and put it on a coffee-pot
|(well, maybe a coffee-pot is too hard, I'll think of something else).
|Waddaya say?
|
|[ this random idea actually due to my fractal-head pal Alain Fourier ]
|	-- seth     seth@miro.berkeley.edu

No, no, NO!  Have you no sense of taste or couth?  One does these sorts
of things with mandrills and TEApots!  Like, for instance, the Utah teapot.
Yea, that's it!

Monkeys?  Ack, Pth!

:^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) :^) 
/\/\ /|  |    /||| /\|       | John M. Olsen, 1547 Jamestown Drive  /\/\
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eva@socrates.SGI.COM (Eva Manolis) (12/06/88)

In article <7980@pasteur.Berkeley.EDU>, seth@miro.Berkeley.EDU (Seth Teller) writes:
> I have this idea, see: you take an image (like any bunch of pixels, could even
> be a picture) and you kind of paste it on a surface, like wallpaper on a wall.
> This way you could make the dullest of polygons look interesting. Like you
> could take a Playmate, or a monkey, or something, and put it on a coffee-pot
               ^^^^^^^^

> 
> 	-- seth     seth@miro.berkeley.edu



PLEASE , must you MEN always include irrelevant sex images in 
	 everything you do ???

	What, are you hard up, or something ??

	-- eva

bouma@cs.purdue.EDU (William J. Bouma) (12/07/88)

In article <7980@pasteur.Berkeley.EDU> seth@miro.Berkeley.EDU (Seth Teller) writes:
>I have this idea, see: you take an image (like any bunch of pixels, could even
>be a picture) and you kind of paste it on a surface, like wallpaper on a wall.
>This way you could make the dullest of polygons look interesting. Like you
>could take a Playmate, or a monkey, or something, and put it on a coffee-pot
>(well, maybe a coffee-pot is too hard, I'll think of something else).
>Waddaya say?
>

   I hacked the MTV tracer to do just this sort of thing a while back. Instead
of specifying the color of an object this way:

f SkyBlue 1 0 0 0 0

You can say:

f function SpherePaintImage /name/of/image/file 1 0 0 0 0

Where SpherePaintImage is a function of the ray intersection with the surface of
(in this case) a sphere. All it does is calculate from the intersection point
which pixel of the image file corresponds. It returns that as the color for that
point on the sphere (instead of SkyBlue). 

   The hack is simple, writing mapping functions is not. I would not want to
try writing one that would map onto the coffee-pot. One simple function that
gets some use just returns the normal to the surface as the color. Another
I use a lot puts grid patterns on polygons.

   Send playmate and monkey images to:
-- 
Bill <bouma@cs.purdue.edu>  ||  ...!purdue!bouma 

josef@ugun21.UUCP (12/07/88)

In her response eva (eva@socrates.SGI.COM) writes:

>PLEASE , must you MEN always include irrelevant sex images in 
>	 everything you do ???
>
>	What, are you hard up, or something ??
>

I always think of mapping VAXen and robots, but then my wife sais:
"Is that all You can think of: technical stuff?"

		Josef Moellers

	paper mail:			e-mail:
c/o Nixdorf Computer AG		USA:  uunet!linus!nixbur!nixpbe!mollers.pad
Abt. EG-3			!USA: mcvax!unido!nixpbe!mollers.pad
Unterer Frankfurter Weg
D-4790 Paderborn
tel.: (+49) 5251 104691

Standard disclaimer: Blablabla opinion blablabla employer blablabla!

msg@fuzz.SGI.COM (Mark Grossman) (12/08/88)

In article <675@wasatch.UUCP>, u-jmolse%sunset.utah.edu@wasatch.UUCP (John M. Olsen) writes:
> seth@miro.Berkeley.EDU (Seth Teller) writes:
> |I have this idea, see: you take an image (like any bunch of pixels, could even
> |be a picture) and you kind of paste it on a surface, like wallpaper on a wall.

What a bozo.  I thought up this technique WEEKS ago.  I already have a
wallpaper program called "paste".  It runs on IRISes, Suns, and Hubbard &
Johnson paint shakers.  I especially like using it to make tie-die patterns
on my airfoil designs.
    -- Mark