Well after seeing what Polluted Planet did with large numbers of interactive particles in java, it got me interested.
So i have decided to have a go at implementing it myself in XNA.
So here it is, my first attempt at it. Currently the algorithm is very rough as you can see from the video there are still some problems that cause the particle to behave a little… umm.. erratic 
Hopefully with abit more time and effort ill get it sorted. At the moment there are 5000 interacting particle on one CPU, hopefully i will beable to push that figue up soon and take advantage of my quad-core system 
3 Responses to XNALiquids 01
Pete January 11, 2008
Looks very lava like!
John December 23, 2010
Fantastic work, how exactly do you get the particle glow for each one? Is it a bitmap or do you apply some form of pixel shader onto it. I'm trying to get used to shaders and HLSL, still trying to work out how to make stuff 'glow'. Add a radius of X amount of pixels and slowly decrease opacity?
mikecann December 24, 2010
Hi John. No its nothing that complicated, its simply a semi-transparrent sprite thats used for the particle. That way then they overlap a little there is some small additive blending going on making the area look brighter.
In my other experiments I have used a standard Bloom post-processing effect to make the particles glow. See and example here:
http://www.youtube.com/watch?v=MocF1IU-5dc
Bloom is pretty simple, it just involves down sampling the frame, then gausian blurring and scaling back up again.