[Sidefx-houdini-list] camera projection mapping

Jed Schwartz jed at jedschwartz.com
Mon Jul 14 15:35:09 EDT 2008


I'm exploring  the possibility of using camera projection mapping  
techniques (used quite successfully in a lightwave project) in our  
current production that calls for a bunch of extreme close up detail  
shots, mixed with broad sweeping moves across  very detailed martian  
terrain.  We have all our terrain built and a great set of very hi- 
res textures matching the DEMs we used to generate the terrain.

Most of our shots are blocked out and approved for final render, so  
were to that stage where we're trying to figure out the most  
practical way to get detail into our shots where we need it- We have  
completed a few shots using Y projection maps with all the usual  
tiling, depth maps et-al- Very labor intensive and lots of extra  
detail generated that the camera will never see-

My colleague who did this in lightwave breaks down his procedure into  
the following steps:

1. Finalize the camera move

2. Select "key" frames for terrain plate paintings
   For a locked-off shot or a very small pan, one "key" painting
   should be OK. For larger camera moves you may need to use several
   paintings to cover the entire terrain seen by the camera. Instead
   of using the (moving) final render camera I'll make a copy of it and
   delete the motion so that each "key" painting camera is separate
   and stationary.

3. Render a "screenshot" from the view of the plate camera

4. Paint on top of the screenshot

5. Project the final texture back through the plate camera onto the
   terrain.

The main reason to use this paint-projection technique is to get around
the problem that ECU images never quite have enough resolution to
look "photorealistic" for my typical MER shots. The disadvantage is
the high amount of labor to set up each shot; the advantage is being
able to put high-resolution detail exactly where it is needed for any
given camera move.-

I'd be most grateful if anyone who has explored this approach to  
projection mapping in Houdini and would be willing to share some  
insight into this process-

Thanks!!

Jed-


More information about the Sidefx-houdini-list mailing list