Not sure if the title is an official term but at 12am I honestly could not

While this is doable in some (most?) 3d modeling programs, I am not sure if

this is doable in jitter. Namely, I am hoping to have 3d objects floating in

space and when they move into the area where a [preferably invisible]

texture is being projected (a texture of a quicktime movie for instance),

their body will reflect a particular part of this otherwise invisible

texture. So, in other words, if a 3d object finds its way into the top-right

corner of the projected texture (which would be invisible otherwise), then

their body would reflect that top-right corner, in effect becoming

This would in effect seem as if the invisible texture in question is being

subtracted against the shapes of 3d objects, allowing only to see parts of

the texture where 3d objects reside. Hence, my [awkward?] title :-).

Any help in this matter is most appreciated!

Composition, Music Technology, CCTAD, CHCI

http://www.music.vt.edu/people/faculty/bukvic/

Not sure if the title is an official term but at 12am I honestly could not
think of a better way to express this.

While this is doable in some (most?) 3d modeling programs, I am not sure if
this is doable in jitter. Namely, I am hoping to have 3d objects floating in
space and when they move into the area where a [preferably invisible]
texture is being projected (a texture of a quicktime movie for instance),
their body will reflect a particular part of this otherwise invisible
texture. So, in other words, if a 3d object finds its way into the top-right
corner of the projected texture (which would be invisible otherwise), then
their body would reflect that top-right corner, in effect becoming
doubly-textured object.

This would in effect seem as if the invisible texture in question is being
subtracted against the shapes of 3d objects, allowing only to see parts of
the texture where 3d objects reside. Hence, my [awkward?] title :-).

Ivica Ico Bukvic, D.M.A.
Composition, Music Technology, CCTAD, CHCI
Virginia Tech
Dept. of Music - 0240
Blacksburg, VA 24061
(540) 231-1137
(540) 231-5034 (fax)
ico@vt.edu
http://www.music.vt.edu/people/faculty/bukvic/
http://ico.bukvic.net


question-about-subtractive-texturing

Did you see my sharing is fun projective texture patch from last

night? This could serve your purpose if you want the projected

texture to be arbitrarily located in the scene. You'd have to change

things a little of course to get multitexturing, but it could easily

be done. The other option which is less flexible but easier on the

GPU and more straightforward to understand is to use object space

texture coordinates with a border color of black and a @wrap

> Not sure if the title is an official term but at 12am I honestly could not

> While this is doable in some (most?) 3d modeling programs, I am not sure if

> this is doable in jitter. Namely, I am hoping to have 3d objects floating in

> space and when they move into the area where a [preferably invisible]

> texture is being projected (a texture of a quicktime movie for instance),

> their body will reflect a particular part of this otherwise invisible

> texture. So, in other words, if a 3d object finds its way into the top-right

> corner of the projected texture (which would be invisible otherwise), then

> their body would reflect that top-right corner, in effect becoming

> This would in effect seem as if the invisible texture in question is being

> subtracted against the shapes of 3d objects, allowing only to see parts of

> the texture where 3d objects reside. Hence, my [awkward?] title :-).

> Any help in this matter is most appreciated!

> Composition, Music Technology, CCTAD, CHCI

Did you see my sharing is fun projective texture patch from last
night?  This could serve your purpose if you want the projected
texture to be arbitrarily located in the scene.  You'd have to change
things a little of course to get multitexturing, but it could easily
be done.  The other option which is less flexible but easier on the
GPU and more straightforward to understand is to use object space
texture coordinates with a border color of black and a @wrap
clampborder.

On 5/31/07, Ivica Ico Bukvic  wrote:
> Not sure if the title is an official term but at 12am I honestly could not
> think of a better way to express this.
>
> While this is doable in some (most?) 3d modeling programs, I am not sure if
> this is doable in jitter. Namely, I am hoping to have 3d objects floating in
> space and when they move into the area where a [preferably invisible]
> texture is being projected (a texture of a quicktime movie for instance),
> their body will reflect a particular part of this otherwise invisible
> texture. So, in other words, if a 3d object finds its way into the top-right
> corner of the projected texture (which would be invisible otherwise), then
> their body would reflect that top-right corner, in effect becoming
> doubly-textured object.
>
> This would in effect seem as if the invisible texture in question is being
> subtracted against the shapes of 3d objects, allowing only to see parts of
> the texture where 3d objects reside. Hence, my [awkward?] title :-).
>
> Any help in this matter is most appreciated!
>
> Ivica Ico Bukvic, D.M.A.
> Composition, Music Technology, CCTAD, CHCI
> Virginia Tech
> Dept. of Music - 0240
> Blacksburg, VA 24061
> (540) 231-1137
> (540) 231-5034 (fax)
> ico@vt.edu
> http://www.music.vt.edu/people/faculty/bukvic/
> http://ico.bukvic.net
>
>
>
>


BTW, regarding the second option, do you mind elaborating upon this one a

bit more? Are you suggesting simply calculating coordinates of the object in

respect to floating texture area and based upon that extracting a portion of

the texture from the texture matrix and then mapping it onto the object in

> From: jitter-bounces@cycling74.com [mailto:jitter-bounces@cycling74.com]

> Subject: Re: [jitter] question about subtractive texturing

> Did you see my sharing is fun projective texture patch from last

> night? This could serve your purpose if you want the projected

> texture to be arbitrarily located in the scene. You'd have to change

> things a little of course to get multitexturing, but it could easily

> be done. The other option which is less flexible but easier on the

> GPU and more straightforward to understand is to use object space

> texture coordinates with a border color of black and a @wrap

> > Not sure if the title is an official term but at 12am I honestly could

> > think of a better way to express this.

> > While this is doable in some (most?) 3d modeling programs, I am not sure

> > this is doable in jitter. Namely, I am hoping to have 3d objects

> > space and when they move into the area where a [preferably invisible]

> > texture is being projected (a texture of a quicktime movie for

> > their body will reflect a particular part of this otherwise invisible

> > texture. So, in other words, if a 3d object finds its way into the top-

> > corner of the projected texture (which would be invisible otherwise),

> > their body would reflect that top-right corner, in effect becoming

> > This would in effect seem as if the invisible texture in question is

> > subtracted against the shapes of 3d objects, allowing only to see parts

> > the texture where 3d objects reside. Hence, my [awkward?] title :-).

> > Any help in this matter is most appreciated!

> > Composition, Music Technology, CCTAD, CHCI

BTW, regarding the second option, do you mind elaborating upon this one a
bit more? Are you suggesting simply calculating coordinates of the object in
respect to floating texture area and based upon that extracting a portion of
the texture from the texture matrix and then mapping it onto the object in
question?

> -----Original Message-----
> From: jitter-bounces@cycling74.com [mailto:jitter-bounces@cycling74.com]
> On Behalf Of Wesley Smith
> Sent: Friday, June 01, 2007 12:43 AM
> Subject: Re: [jitter] question about subtractive texturing
>
> Did you see my sharing is fun projective texture patch from last
> night?  This could serve your purpose if you want the projected
> texture to be arbitrarily located in the scene.  You'd have to change
> things a little of course to get multitexturing, but it could easily
> be done.  The other option which is less flexible but easier on the
> GPU and more straightforward to understand is to use object space
> texture coordinates with a border color of black and a @wrap
> clampborder.
>
> wes
>
> On 5/31/07, Ivica Ico Bukvic  wrote:
> > Not sure if the title is an official term but at 12am I honestly could
> not
> > think of a better way to express this.
> >
> > While this is doable in some (most?) 3d modeling programs, I am not sure
> if
> > this is doable in jitter. Namely, I am hoping to have 3d objects
> floating in
> > space and when they move into the area where a [preferably invisible]
> > texture is being projected (a texture of a quicktime movie for
> instance),
> > their body will reflect a particular part of this otherwise invisible
> > texture. So, in other words, if a 3d object finds its way into the top-
> right
> > corner of the projected texture (which would be invisible otherwise),
> then
> > their body would reflect that top-right corner, in effect becoming
> > doubly-textured object.
> >
> > This would in effect seem as if the invisible texture in question is
> being
> > subtracted against the shapes of 3d objects, allowing only to see parts
> of
> > the texture where 3d objects reside. Hence, my [awkward?] title :-).
> >
> > Any help in this matter is most appreciated!
> >
> > Ivica Ico Bukvic, D.M.A.
> > Composition, Music Technology, CCTAD, CHCI
> > Virginia Tech
> > Dept. of Music - 0240
> > Blacksburg, VA 24061
> > (540) 231-1137
> > (540) 231-5034 (fax)
> > ico@vt.edu
> > http://www.music.vt.edu/people/faculty/bukvic/
> > http://ico.bukvic.net
> >
> >
> >
> >


Here's a start. BTW, I made a mstake in my previous email. The borer

Here's a start.  BTW, I made a mstake in my previous email.  The borer
color should be 1 1 1 1.