Maya: particle expression

[tijuana]

Hi

I have 3 emitters in a scene emitting cloud particles with the particleCloud shader applied. The resulting 3 particle shapes have seperate expressions controlling the radiusPP attribute:


particleShape3.radiusPP = rand(0,0.01);

particleShape4.radiusPP = rand(0,0.05);

particleShape5.radiusPP = rand(0.05,0.1);



What I would like to do is control the glow intensity attibute of the particleCloud shader with the radiusPP values so that the smaller the particles the higher the glow and the larger the particles the lower the glow so the the smaller particles glow more than the larger ones.

I would also like to control the density attribute of the particleCloud shader with the same radiusPP values so that the smaller particles have a higher density value than the larger ones.

I am new to expression writing and have had a fair go at this but don't seem to be getting it quite right! Can anyone help please?


Thanks
Emma