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Kurt-olsson

DX11 Shadow mapping = ok for large open areas?

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Kurt-olsson    254
Sorry about my shadow-spam questions! =)

But i start to like DX11 really much and the whole Shader Approach is so cool, so much power with to little code!

I am starting to understand how the whole shadow mapping works.

Depth buffer calulations and render to texture etc.
But i dont want to study this technique all day(s) long to find out that it only can handle small areas (1024 textures) that only shadows a part of my scene.

My game is a FPS like Quake so my question is:

can shadow mapping handle big scenes/outdoor scenes like this?

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Ashaman73    13715
[quote name='KurtO' timestamp='1348659830' post='4983948']
can shadow mapping handle big scenes/outdoor scenes like this?
[/quote]
Yes, the trick is, that you only calculate the shadows in front of the camera and blend it out for scene elements farther away. Though you will need some additional efforts to get shadows working for larger viewing distances without using huge shadowmaps. The most prominent approach is CSM (cascading shadow maps aka parallel split shadowmapping). Edited by Ashaman73

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Tasaq    1530
[quote name='KurtO' timestamp='1348659830' post='4983948']
But i dont want to study this technique all day(s) long to find out that it only can handle small areas (1024 textures) that only shadows a part of my scene.
[/quote]
You can have up to 8192 size rt's, but that can be an overkill.
As Ashaman said, CSM is what you are looking for. With it, you can achieve decent look even with 512x512 shadow maps (if we take that you will use some shadow map antialiasing techniques). Idea behind it is preety simple, implementation is a bit tricky but not impossible. If you have directx sdk there's a demo of csm, check it out :)

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