Lionel Maiaux (maiaux++at++platine.corys.fr)
Mon, 16 Sep 1996 12:24:26 -0600
I think I found a bug in the libpfdu mesher with the retessalate option on.
I have 2 adjacent quads mapped with the same texture but with "mirrored"
(english?) texture coordinates like this :
Texture :
-------
...................
. .
. .
. +---- .
. | .
. +-- .
. | .
. +---- .
. .
. .
...................
2 Quads with texture coordinates:
--------------------------------
+-----------------+-----------------+
|(1,1) (0,1)|(0,1) (1,1)|
| | |
| ----+ | +---- |
| | | | |
| --+ | +-- |
| | | | |
| ----+ | +---- |
| | |
|(1,0) (0,0)|(0.0) (1,0)|
+-----------------+-----------------+
If the retesselation orders the vertices like the next figure, all is OK ...
+0 +2 +4
| * | * |
| * | * |
| * | * |
| * | * |
| * | * |
1+ 3+ +5
... but sometimes, the retesselation orders the vertices like that :
0+-----------+1 +3
* * *
* * *
* * *
* * *
* * *
2+ 4+-----------+5
In this case, texture coordinates are interpollated between vertices 2 and 3
from (1,0) to (1,1), so 's' coordinate doesnt change !
Should it be possible to choose systematically the correct way of retesselation
???
--
-------------------------------------------------------------------------------- Lionel Maiaux
l.maiaux++at++corys.fr
--------------------------------------------------------------------------------
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