As somebody who is new to the Unity Engine, I am curious regarding the following:
Is it theoretically possible to create a script (in JavaScript, C#, or Boo) that allows objects to cast dynamic shadows? Or perhaps dynamic ray tracing?
I guess the more accurate question I want to ask is, how customizable is the Engine through the Unity Indie package?
P.S. I am fully aware that the free version of Unity does not support dynamic shadow casting. However, I’d like to know just how much you can customize the engine with the scripting tools.
i’m really not very much into this topic, but as far as i know you don’t have access to custom shaders in unity indie, which means that you would have to calculate all this on the cpu instead of gpu, so it might be possible, but most probably not in realtime if your scene is larger than 2 cubes. i’m no expert though …
I’m not sure how far you can go with the indie version (I started with Pro from the get-go with my company), but the Pro version has a lot of programmability.
I think you can cast rays in the indie version (via the physics engine?), but I’m not sure. As for generating your own shadows, that might not be possible as (I’m pretty sure) the ability to render a shot to a texture (that is, make a rendering to project as a casted shadow) I think is Pro only.
Don’t take my word for it though; just talking off the top of my head.
That’s not exactly true. You do have access to custom shaders, and I’ve written several myself (for atmospheric scattering, dynamic clouds, etc).
What you don’t have access to that you’d need for VSM or other types of dynamic shadows, is the ability to use render targets.
I know of several people who’ve done old-school shadow volumes in Indie that looks okay, but shadow volumes just aren’t ever going to be quite as nice as shadow mapping.
As for dynamic raytracing, I suppose that’s possible but probably not practical. You can create read/write textures in Indie (but not usable as render targets), there’s easy access to all scene geometry, and ray casting is simple enough, so you could theoretically do that on the CPU, but you’ll have a hard time making it performant enough for a realtime game.