TEXMAP extension thoughts and findings.

[Roland Melkert]

I attempted to test CYLINDRICAL with LDCad last night, and either got no image (P3 even with P1) or a scrambled one (P3 even with P2).  It was very strange.

Seems to work fine for me (in 1.6a):

  cyl.png (Size: 72.75 KB / Downloads: 132)

Using

Code:

0 Cyl texmap test
0 UNOFFICIAL PART
0 BFC CERTIFY CCW

1 16 0 0 0 1 0 0 0 1 0 0 0 1 s\3626bs02.dat
1 16 0 4 0 13 0 0 0 13 0 0 0 -13 1-8cyli.dat
1 16 0 4 0 -13 0 0 0 13 0 0 0 -13 1-8cyli.dat
1 16 0 4 0 13 0 0 0 13 0 0 0 13 2-4cyli.dat
1 16 0 4 0 0 0 8 0 -6.4 0 8 0 0 t04o6250.dat
1 16 0 4 0 -8 0 0 0 -6.4 0 0 0 8 t04o6250.dat
1 16 0 17 0 0 0 -8 0 6.4 0 8 0 0 t04o6250.dat
1 16 0 17 0 8 0 0 0 6.4 0 0 0 8 t04o6250.dat
1 16 0 4 0 0 0 -8 0 -6.4 0 -8 0 0 t04o6250.dat
1 16 0 4 0 8 0 0 0 -6.4 0 0 0 -8 t04o6250.dat
1 16 0 17 0 0 0 8 0 6.4 0 -8 0 0 t04o6250.dat
1 16 0 17 0 -8 0 0 0 6.4 0 0 0 -8 t04o6250.dat


0 !TEXMAP START CYLINDRICAL 0 4 0  0 17 0   0 4 -13  90 smile.png
1 16  0 4 0  -9.1923 0 9.1923  0 13 0  -9.1923 0 -9.1923  1-4cyli.dat
0 !TEXMAP END

and

Code:

0 Cyl texmap test 2
0 UNOFFICIAL PART
0 BFC CERTIFY CCW

0 !TEXMAP START CYLINDRICAL 0 4 0  0 17 0   0 4 -13  90 smile.png
1 16  0 0 0  1 0 0  0 1 0  0 0 1 3062a.dat
0 !TEXMAP END

As you see it uses P3 at the top, I will change this for 1.6b unless anyone thinks bot planer and cylindrical should use top for uniformity ?

In other news, my buddy changed Foundry last night to render textures correctly on transparent geometry, something that none of the platforms currently does right (including Foundry, as the reference platform).  LeoCAD is close, he's using a shader to get the desired effect.

(The issue is, nearly every renderer will render the texture transparently when applied to transparent geometry, when the alpha of the texture and the alpha of geometry need to combine, with opaque alpha on the texture overriding any alpha of the underlying part.  Both GL_DECAL and GL_REPLACE give the wrong results).  I presumed we'd HAVE to go to a shader solution (something I don't really mind because it was always presumed to be needed for proper GLOSSMAP support), but Foundry is apparently doing a double render manuever to get the desired results.

Transparent is very problematici ndeed (especially since LDCad 1.x uses fixed piped line), it also has to do with draw order on top of the normal trans draw order issues.

2.0 uses >= GL 3.0 so custom shaders for everything will have to revisit the problem when the time comes.