Re: XSI Triangulation to CDH

[François Painchaud <francois.painchaud(at)sympatico.ca>]

Some good links about triangulation algorithms and libraries to keep you busy:
www.cs.cmu.edu/~quake/triangle.html
www.cs.berkeley.edu/~flab/cs294-5/project2/mesh.html
http://gts.sourceforge.net
www.andrew.cmu.edu/user/sowen/software/triangle.html
www.cs.berkeley.edu/~jrs/mesh/

François

Le 2007-02-07 21:45, Wessam Bahnassi a écrit :

A pretty easy triangulation algorithm (it might be the one XSI is using, but
I'm just guessing) is the GLUtesselator. For the matter of CDH, I had to
code DSK|ShaderBass for a while, and that was basically another real-time
rendering engine for XSI. It used CDH though, and what we did was to attach
a custom RT shader node to the material, and in our plug-in, we ask the
GraphicsSequencer to render all objects using materials with that shader
attached. This way, you get your triangulation automatically done by XSI the
way it does it for all other RT shaders.

I hope this helps,
Wessam Bahnassi
Microsoft DirectX MVP,
Programmer
Electronic Arts
--
'Talk is cheap because supply exceeds demand'
  

-----Original Message-----
From: owner-xsi(at)Softimage.COM [mailto:owner-xsi(at)Softimage.COM] On
Behalf Of Alan Jones
Sent: Wednesday, February 07, 2007 6:47 AM
To: XSI(at)Softimage.COM
Subject: Re: XSI Triangulation to CDH

Hi André,

Unfortunately we can't access this - though I did request the ability
to access the underlying representation of any set of components.

i.e. from a selection of polies get the polygons which make the
subdivided version, for edges get the edges which represent the
subdivided version of those edges.

It would allow things like what you're suggsted as well as building
proper wireframe rendering solutions (pushing the sudivided mesh as
curves to the renderer etc).

Anyone else who wants to add their name to that box would be great for
getting Soft to push it up the priority ladder :-)

Cheers,

Alan.

On 2/7/07, André Adam <a_adam(at)49games.de> wrote:
    

Hello alltogether,

does anybody familiar with the C++ SDK know if it is possible to
reference the triangles resulting from XSI's internal triangulation
      

of
    

polygon meshes from a given facet?
We are currently trying to get the triangle structure of selected
objects into our Custom Display Host, and since we have to draw the
objects through their polygon clusters (holding the material), we
      

can't
    

simply access the triangles using GetTriangles() from the Geometry
class, since this is only available for the whole object.

Another approach would be to mimic XSI's triangulation inside of the
CDH, any chance of gettung access to the internal algorithm?

Thanks for any hint, cheers!

    -André