Open-Source reimplementation of Westwood’s Command & Conquer: Red Alert game engine, updated to use the hardware acceleration of modern video cards using OpenGL and OpenAL for sound playback. It runs natively on Windows, Linux and Mac OS X. The game was designed with modifiability in mind, but is not identical to the original. Campaigns and mods made for the legacy game won't work out of the box.
We are currently experimenting with lighting as well as scripted flash effects and matching sounds.
I spent a LONG time getting something like this working in Tiberian Sun, I think it can really add a nice ambient effect to maps, hopefully see snow at some stage too?
Weather effects are work in progress. Right now only flashing, day-night scripts (changing map lighting) and ambientsounds are possible.
I have a relatively largish animation (not laggy) I use for rain attached to invisible buildings that requires power. Map triggers changing the owner of pre-placed off map power stations can stop and start a rain cycle. I imagine OpenRA can develop a way better system than this.
It will be done through particle effects. See Github.com for implementation details and Imgur.com for a preview.