Hello,

I want to use the "triscan" macro found on the POV newsserver year 2000.. It
easily works in Pov3.5 and tesselates any object.. I know it has bugs but
never mind.. The demo files should work, right? Why do I get a big big mess?
I had to write a macro myself to view the mesh, maybe this is the problem.
"Triscan" outputs a RAW file. I need to load it into POV as a mesh. After
what I see, it's just all the vertices, suited for direct loading into a
mesh. What are your results with the macro?  I tried with MegaPOV too, to be
sure it wasn't caused by Pov3.5.


Hugo

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Hugo wrote:
> 
> Hello,
> 
> I want to use the "triscan" macro found on the POV newsserver year 2000.. It
> easily works in Pov3.5 and tesselates any object.. I know it has bugs but
> never mind.. The demo files should work, right? Why do I get a big big mess?
> I had to write a macro myself to view the mesh, maybe this is the problem.
> "Triscan" outputs a RAW file. I need to load it into POV as a mesh. After
> what I see, it's just all the vertices, suited for direct loading into a
> mesh. What are your results with the macro?  I tried with MegaPOV too, to be
> sure it wasn't caused by Pov3.5.
> 
> Hugo



Hugo:

Sorry, I just saw this. You probably got your answer long ago, but 
I don't see any replies, so I'll add a comment. Triscan was 
developed under MegaPOV as an experiment in tesselation of POV
primitives. It wasn't intended to turn POV primitives into POV
meshes as the primitives are already much better quality. The
routine only ever got "fair" results at best in conversion, so
it's primary intent was to allow limited translation of POV
objects for importation into other packages, like Moray UDOs,
Leveller reference shapes, OBJ props in Poser, etc. To do this,
you must take the RAW file and convert it using a program such
as 3DWin which reads in RAW files and turns them into any number
of other formats (including, if you really wanted for some reason, 
POV triangles). The one exception is Leveller reference shapes
(see demo 4), which I made an output option only because I know
of no converter that included LSL files at the time of Triscan's
creation.


Charles Fusner
----
The Silver Tome ::  http://www.silvertome.com 
0x06: I am NOT a RESOURCE. I am a free() mem!!
0x02: Aaaahahahahahahaha...

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Hi Charles,

Thanks for your reply! You're the only one who replied, and no, I never got
an answer to my question. I had to leave Triscan. I still wonder how it's
possible for the program to create a raw file that is *not* compatible with
the Povray mesh syntax, as if the vertices are not stored in the cartesian
3d space! (I think it's called).

Well, I wanted the tesselated objects back in Povray - only - because I have
many ideas for manipulating them in SDL (Povray's scene description
language). Meshes are much more flexible than primitives, though not as
...smooth.

I see that Jerome Grimbert is working on a tesselation patch coded in C,
which means it'll be faster but not accessible in SDL as such. But the
important thing will be to get an output of all vertices and faces. I hope
it will soon be official part of Pov.

Regards,
Hugo


Charles Fusner wrote:
> Sorry, I just saw this. You probably got your answer long ago, but
> I don't see any replies, so I'll add a comment. Triscan was
> developed under MegaPOV as an experiment in tesselation of POV
> primitives. It wasn't intended to turn POV primitives into POV
> meshes as the primitives are already much better quality. The
> routine only ever got "fair" results at best in conversion, so
> it's primary intent was to allow limited translation of POV
> objects for importation into other packages, like Moray UDOs,
> Leveller reference shapes, OBJ props in Poser, etc. To do this,
> you must take the RAW file and convert it using a program such
> as 3DWin which reads in RAW files and turns them into any number
> of other formats (including, if you really wanted for some reason,
> POV triangles). The one exception is Leveller reference shapes
> (see demo 4), which I made an output option only because I know
> of no converter that included LSL files at the time of Triscan's
> creation.

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Hugo wrote:
> Thanks for your reply! You're the only one who replied, and no, I never got
> an answer to my question. I had to leave Triscan. I still wonder how it's
> possible for the program to create a raw file that is *not* compatible with
> the Povray mesh syntax, as if the vertices are not stored in the cartesian
> 3d space! (I think it's called).

Hmm. Can't say without seeing what results, but perhaps some of the
normals got mixed in with the vertices. I don't know what kind of
results you got when you tried it, but that's the one really weird
thing I did by accident once while I was creating it. I had a good 
laugh looking at the results, although they were useless, they were 
definitely bizzare looking. It turned a simple sphere into this
insane spiky creation from some strange alien universe. 
 
> I see that Jerome Grimbert is working on a tesselation patch coded in C,
> which means it'll be faster but not accessible in SDL as such. But the
> important thing will be to get an output of all vertices and faces. I hope
> it will soon be official part of Pov.

That's definitely good news. I'd be happy to see such a patch. 
While I was experimenting, the conclusion I came to was that a
tesselation patch to POV itself was probably the only way to get 
really decent quality meshes. "Scanning" just didn't seem to work 
more than low to medium quality, although I had high hopes for 
it initially. 

Charles

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> "Scanning" just didn't seem to work more than low
> to medium quality, although I had high hopes for
> it initially.

Well, maybe you'll be surprised to know that Jerome's patch also scans the
surfaces. He seems to have broken the barrier with angles of 90 degrees..
But his algoritm does not feature triangle-decimation (mesh reduction) at
least yet, so good replications needs a whole lot of triangles.

> It turned a simple sphere into this insane spiky
> creation from some strange alien universe

Just my experience! However I haven't mixed up the vertices and normals -
I'm pretty sure. Besides I tried all combinations, and I fixed some comma
problems in the raw file, that confuses the parser in Pov3.5.. But anyway
thanks for your efforts to triscan! Even though the macro may (soon) be
outdated when Jerome releases his patch (if he haven't done so... I'm not
sure) your macro has served as reference and inspiration.  :o)

Regards,
Hugo

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