Shadow Capture/RTR
landrew
Posts: 2
Can anyone tell me what the difference between shadow capture technique, and the RTR environment that David Brinnen sells?
Thanks.
Comments
@landrew - our products Shadow Capture and Ready-to-Render environments have the following difference: the shadow capture ones use a shadow catcher ;) the RTR not. Ok, not helpful.
An HDRI can be used as light source (IBL) and as backdrop. This backdrop is actually a sphere with (as far as Bryce goes) an infinite diameter. If you put an object on the virtual floor, it floats. If you put in an infinite plane or whatever, the floor gets covered but the object can cast a shadow.
So shadow capturing is a method to have the ground on which an object is positioned fully transparent but the object casts a shadow and it appears as if that object were standing on the floor that the backdrop depicts. This method also works for shadows that are cast on a wall (which is again at infinite distance). In a nutshell, transparent faces and negative lights are used to make this effect work. The theory is rather simple, setting a scene up may need a bit getting used to. Particularly to get the shadow intensity right. The good thing about this method is that it is versatile.
RTR uses another approach. It is easy set up and works right away, though it is limited to the HDRI used. Here, the floor is rendered separately and from this render, some sort of an UV map is made. This map is then put on a flattened cube at the correct position so that the camera angle and the HDRI matches up with the uv map on the cube. An RTR product has these things already set. All you have to do is bring in your objects and pose them on the cube. Any light will create the correct shadow of the object. The camera can still be moved around but the range is restricted. And you can boolean a hole in that cube and the RTR still works, which is more difficult to get right with the shadow capture method.
Horo, Thanks for the quick reply and explanation.
Looks like I,m bound for RTR!
OMG......I understood that Horo.....wow maybe my brain is working now....Cool
@landrew - I wish you a good start and much fun.
@Trish - it always worked, there was just a time I didn't exactly know how ;-P