Warp wrote:
>   As you might guess, there's no "better" algorithm. It's always about
> compromises. One algorithm is better at some things and worse at others.

Thank you for the detailed explanation. I figured the algorithms had 
different strengths, but I couldn't figure out just from understanding the 
basics of the algorithms what the strengths were.

>   Shadow mapping is easier to implement and often (although not always)
> faster. Its problem is that it you always have to make a compromise between
> accuracy and memory usage (the larger the shadow maps, the more accurate
> the result, but the more RAM is required; more accuracy might also affect
> rendering speed by some amount). 

Huh. I always wondered why old games had very pixelated jaggy shadows, but 
now that you mention it, if you do the shadow projection on a very small 
depth buffer, that's just what you'd expect. Cool.

> you can "cheat" and add the moth's shadow to the correspondent shadow maps

Yeah, I can see that.

XNA even has a constructor for the Matrix class where you give it a point 
and a plane, and it constructs a transform that maps a point to where it 
would cast a shadow onto that plane. I guess that's exceedingly fast as long 
as you're only casting shadows onto flat surfaces, like running across 
simple terrain or inside a corridor or something.

Now, if only I could get inspired to actually sit down and work on my next 
game, I'd be good. :-)

-- 
Darren New, San Diego CA, USA (PST)
   Serving Suggestion:
     "Don't serve this any more. It's awful."

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