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OpenGL Soft shadow maps - how important are they?

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I keep reading about the various difficulties people have with soft shadow maps. So I wonder: are they worth it? I mean, of course they look nice in the examples, but how much of a visual impact do they really have in a full game? Are they indeed essential for the visual quality, or are they less relevant, similar to, say, the various relief mapping methods (which look good in the demos&examples, but have little real-world advantages over parallax mapping while being significantly more expensive)? One case where they could be important is when rendering rather dark indoor areas, where the shadows are easily visible, and the contrast between lit and unlit areas is very big. Any thoughts? EDIT: I forgot to mention two things: 1) I do know that shadow maps for wide area lights (typically sunlight) require some softening, otherwise it will look very pixelated, unless one uses huge shadowmaps. This is one case where soft shadows do have a high visual impact. 2) I am aiming for OpenGLES 2 support, and therefore cannot use MRT's or floating point buffer formats. This is why I am thinking if it is really worth the trouble. [Edited by - dv on February 11, 2010 4:49:19 PM]

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I think that shadows are important, because the human brain is able to utilize this information to increase it perception of what it sees. Everything else, if it is just a black blob under the player or a high-end soft shadow, is about quality.

So, it comes down to a trade off of quality vs. costs, which is at least your decision. There're many way to implement soft shadows with according quality, some ways are quite easy (i.e. PCF) others need more work, eventually choose something you are happy with and which will be feasable from your point of view.

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