Is there a way, like in the project window, to hide an object but to still have its shadow?
|Answer:||Unfortunately, there's no easy way to do this and get accurate shadows. Even with Shadow Catcher - your object will obscure it's own shadows. |
If you want fast soft shadows that you can combine with a rendered scene to give you some great effects - you can do the following...
Make your entire scene (except cameras and lights) into a shape object. Render the scene with raytracing as normal, no shadows on anything. Just full color, full resolution. You can brighten all of the lights in your scene if you want to - since in the following paragraph I'll explain how to create a shadow scene pretty easily - which will be multiplied with this rendering (either in video or in still, photoshop).
Then, make a texture that's 100% diffuse, 100% ambient, white. No reflection, no specular, nothing else. Apply that texture to your scene and render it with raydiosity with the the following settings:
Texture Detail: Coarse (only grayscale - no textures)
Collected Light Amplifier - 1.0
Raytracing Esoterica (through the raydiosity dialogs above)
Maximum Reflectivity Recursion - 0
Maximum Tracing Block Size - 12
I guess this information should be good for anyone trying to get soft shadows at near raytracing speeds. In my tests - the settings here resulted in about a 1 second increase over rendering time of simple renderings from Raytracing Good. My test scene is a cube, square, pyramid, cone and cylinder on a ground plane with one light.
Your mileage may vary, but this is a good start to getting some sweet rendering speeds for soft shadows.