rpc's and their shadows

[MikeGentile]

i just found this site, and absolutely love it.

 

i wanted to throw a question out there since most people are using rpc in one form or another.

what are some of the techniques and work arounds to get them to cast shadows? any tips would be greatly appreciated.

 

thanks

mike

[nisus]

Hi mark,

 

I'll check out a link for a tutorial on rpc-shadow-cast.

 

rgds

 

nisus

 

[ November 04, 2002, 06:12 PM: Message edited by: nisus ]

[STRAT]

you dont even need a tut on casting shadows. what seems to be your problem, only i get perfect shadows all the time?

[MikeGentile]

thanks for the replies.

the method that is on the rpc site requires a light for every tree. we've tried that method in house and dropped it for some reason which i'll look into today. don't you find that render times increase with so many lights? do you ever group a bunch together? i'm asking this becauase now we have the rpc seniors and we're making shadows for them....it would be nice to have one method for any rpc that we drop into our scenes

[Fermi Bertran]

Originally posted by MikeGentile:

...it would be nice to have one method for any rpc that we drop into our scenes

Mike,

 

If you want RPC to cast shadows you must do 2 things.

 

- Edit the RPC object properties and check "cast shadows"

- INCLUDE the RPC objects and the surfaces receiving the shadows in the sahdow casting light (this probably mean including everything in yur scene actually).

 

Doing both simultaneously will makde them to cast shadows.

 

Last, since RPC are bitmaps that use opacity map, you'll need Raytraced shadows to support transparency, and the light coming from a similar angle of that of the camera, light vector perpendicular to camera vector and you get no shadows becasue RPC are flat geometry.

 

Don't disregard the projector light, may turn very efective, and not only for the RPC.

 

hope it helps

 

[ November 05, 2002, 03:44 PM: Message edited by: FB ]

[MikeGentile]

thanks fermi.

we've tried a card or billboard grouped with the tree and included in a raytrace light, however it doesn't really fit into our pipeline. the raytrace light takes too long to render, because generally our scenes contain over 8 million pollys and sites animations have close to 2000 frames with various scenes and lighting setups. also a raytrace light cast's shadows that are too crisp and don't falloff like real shadows. any other suggestions?

[mbr]

What I've done with animations is to duplicate the directional light, making one that is raytraced for the building shadows and RPC shadows, then one soft mapped for the cars and things with high poly counts. I actually posted about this a while back...

1. Directional Light - raytraced

Include: RPC objects and ground surface (which you'll need to have the shadows cast onto something)

2. Directional Light - soft shadow mapped

Include: All other objects (again, include the ground surface)

3. Directional Light - with a NEGATIVE amount, this will counter the doubled amount of light from the duplicated direct light

 

Pretty sure this is how I did it and it worked wonderfully. If you have any problems with this setup, let me know and I'll go back and double check to make sure this is the correct setup.