Sign in to follow this  
freakchild

dynamic lighting

Recommended Posts

It's been a number of years since I did any sort of graphics programming and I am getting back into it. There's an awful lot to catch up and one of those areas is lighting. What I am looking for is information on up to date lighting techniques. I have been googling, but most of what I can find seems to refer back to basic shading techniques implemented in a pixel shader. What I am looking for is information on techniques that allow me (for example) to have one light, above a sphere, which is a above a floor. If I was to use the basic shading techniques suggested then the light would affect the floor, but the sphere would not occlude the light. I understand I could put a shadow down in a number of ways, but this would still happen either before or after the light is applied to the surface under the sphere. I find plenty of articles on deferred rendering and the lighting algorithms mentioned for these techniques appear to get me what I want easily enough. However...I'm not looking to implement a deferred renderer.

Share this post


Link to post
Share on other sites
Simply adding shadows (using shadow maps for example) will make any shading system look a lot more modern. Other things that you should consider are high dynamic range rendering and physically (more or less..) correct shading models.

Share this post


Link to post
Share on other sites
The problem is, if you're looking for up to date realtime lighting techniques, then they don't have things like shadowing. There are new techniques which try to include shadowing terms into the lighting calculations, but these are still a ways off from being true realtime solutions (by that, I mean for large scale applications like games, with numerous light sources, objects, AI, physics, collision detection, etc, all at once).

You might want to look into ambient occlusion or realtime radiosity, though. Those might offer what you are looking for, but again, are still a ways off from being able to use them in a large scale realtime environment.

Share this post


Link to post
Share on other sites
If I correctly understood your question, then you are looking for either shadow volumes or shadow mapping algorithms.
Th first one was used in a few of recent games using the doom 3 engine (doom3, quake 4, fear and prey, for example).
The second is often prefered due to the fake soft shadows and the many variations that make it possible to go for quality or speed, outdoor vs. indoor, far or near and so on.
Give a look to the unreal 3 engine site and the videos it shows. There is also a few interesting videos about the upcoming crysis, wich will use dynamic shadowing using soft shadows.

A few links:
unreal engine
wikipedia shadow mapping
wikipedia shadow volumes
crysis

There are a lot of papers about real time shadowing (mostly shadow mapping)... many discussions about SM implementation can be found here on gamedev with the search tool...

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this