brett''s code works pretty good for basic rain, I might add an alpha value to it as the solid line looks a little to obvious perhaps even change the color to a shade of grey? a particle system would work better for the dynamics of how the rain falls rather then have it all going in perfectly straight lines.

l8r,

Particles are good for snow because snowflakes are large and slow-moving. No one looks at rain and sees particles, however, so it makes little sense to use anything other than lines for it. If you wanted to get fancy, you could make the lines have a trail that fades out, as opposed to being one line of constant brightness. You''ll probably have to take into consideration the user''s system -- if it''s hardware T&L, do something fancy. Otherwise, make it relatively simple.

~CGameProgrammer( );

Actually, you could use a detail level option to change from rendering simple whit line that all fall the same for low detail on low end systems. or have a particle system setup (this is what I originaly ment) to produce slight variations in the rate and angle of fall, and interaction with wind gusts. and slight variations in the color and length of the lines to simulate different size rain drops.
perceptions of reality can be created by producing slight bits of chaos in the otherwise orderly presision of computers.

stealing this idea from looking at some soccer game on the ps2:
make a particle engine that just has lines travel down the screen at some slight angle. make the lines random length and have them stop at a random Y, thus, they look like they''re of varying distance and size and it''s very light on your processor

NO, NO, NO, NO!!!!!!!

unless you are doing realy heavy rain, or prehaps snow, DON''T use a particle engine...

What works best is FOG!!! a nice fog (fiddle with the values till you get it) the only thing to do on a per-drop basis is when a drop hits the ground, and then only drops near you, and usualy works best if you have puddles, and only draw the splashes in them.

ANDREW RUSSELL STUDIOS
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