Re: [COEN-290] doubts on final


Dave Shreiner (shreiner@sgi.com)
Tue, 20 Mar 2001 12:30:58 -0800 (PST)


TAMANNA SAIT writes:
> Hi Dave
> I had a couple of doubts:
> 1. Lighting is done in eye coordinate space ..right???

   yes.

> 2. What about texturing from the notes i gather that when we generate the
> texture if we generate in eye space the object appears to be floating in the
> texture and if we do it in world space the texture appears as a wall paper
> around the object si i assume that we generate the texture and do texture
> mapping in worl space. Am I right???

   The topic that I think you're discussing is linear texture coordinate
generation. In that mode, as specified by the last parameter in

  glTexGen( GL_{S,T,R,Q}, GL_TEXTURE_GEN_MODE, GL_{EYE,OBJECT}_LINEAR);

determine which space the texture coordinate computation will be done
in. For GL_EYE_LINEAR, the texture generation planes specified are
transformed into eye coordinates, whereas for, GL_OBJECT_LINEAR, the
planes specified remain in world coordinates, and the computations occur
there.

> 3. Is ray tracing also done in eye space or world space??/

   World space, mostly.

> Thanks
> Tamanna
> _________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.

-- 

Thanx, Dave

---------------------------------------------------------------------

Dave Shreiner <shreiner@sgi.com> Silicon Graphics, Inc. (650) 933-4899



This archive was generated by hypermail 2.0b3 on Tue Mar 20 2001 - 16:39:42 EST