topic GDL texture mapping coordination in Libraries & objects

GDL texture mapping coordination

Anonymous — Tue, 05 May 2009 12:19:16 GMT

If I define a texture in GDL and create a 3D object, i.e a polygon with this material, how can I start the texture from the object's local origin? Whatever I do, the texture starts mapping from the plan's origin, and not the object's.

Including for instance:
TEVE 0, 0, 0, 0, 0 !#1
TEVE 0, 0, 0, 0, 0 !#2
TEVE 0, 0, 0, 0, 0 !#3
TEVE 0, 0, 0, 0, 0 !#4
COOR 256, 1, 2, 3, 4
has absolutely no effect on the texture's mapping.

Re: GDL texture mapping coordination

Anonymous — Tue, 05 May 2009 19:53:42 GMT

Try this:
base
vert 0, 0, 0
vert 1, 0, 0
vert 0, 1, 0
vert 0, 0, 1
coor 2 + 256, -1, -2, -3, -4
body -1

Re: GDL texture mapping coordination

David Collins — Wed, 06 May 2009 07:30:50 GMT

One thing that's counter-intuitive here is that the VERT/COOR statements must be placed after the object code.

Also remember to place a BODY -1 statement before the object code as a companion to the one at the end of the VERT/COOR statements. This makes sure that the new texture origin applies apply only to the specific object. Of course, several objects can be included between the the BODY -1 statements. A stray BODY -1 anywhere in between the object code and the VERT/COOR statements will cancel the texture change.

Another thing: Apply the origin changes to the VERT/COOR statements, along with the required DEL statements, instead of trying to work out the vert vectors.

Here's what works for me:

MATERIAL brick

BODY -1

PRISM_ 5, 0.10,
0,0,15,
0,1,15,
1,1,15,
1,0,15,
0,0,-1

ROTy 90
ADD 0.30, 1.20, 0.00
base
vert 0, 0, 0
vert 1, 0, 0
vert 0, 1, 0
vert 0, 0, 1
coor 2 + 256, -1, -2, -3, -4
DEL 2

BODY -1

Re: GDL texture mapping coordination

Anonymous — Wed, 06 May 2009 08:49:12 GMT

Thank you both for the answer. My script was faulty, and also in the wrong order, before the object. Yes, that's quite counter-intuitive.

Re: GDL texture mapping coordination

Anonymous — Tue, 23 Jun 2009 21:33:42 GMT

Is it possible in GDL (with TEVE and COOR statements) to force texture to follow the direction of the TUBE's object space curve path? Picture shows actually what I want to achive (red arrow) on TUBE object, the right woodgrain direction on my door wood elements.

This is the custom TUBE object on which I want to try to solve the problem.

set material mat

body -1

tube 4, 7, 16+32,
0, 0, 0,
0.1, 0, 0,
0.1, 0.05, 0,
0, 0.05, 0,
0, B, 0, 0,
0, 0, 0, 0,
A, 0, 0, 0,
A, B, 0, 0,
0, B, 0, 0,
0, 0, 0, 0,
A, 0, 0, 0

body -1

thanx

Re: GDL texture mapping coordination

Anonymous — Wed, 24 Jun 2009 01:54:24 GMT

Oddly the tube element doesn't map textures well at all. I ended up using GDL primitives to create my own version of a tube with inbuilt texture mapping.

Re: GDL texture mapping coordination

Erich — Wed, 24 Jun 2009 02:06:15 GMT

Interesting idea Andrew, I will have to try it.