i've been playing around with this for a few hours now and i'm beginning to think i'll have to do it all by hand.
here's the problem.
i'm animating water molecules passing thru layers of the skin - in diagram style.
so i want the little blue particles to weave there way thru the 'brickwork style' cells of the skin. the alpha is the gaps between the 'brickwork cells', imagine its the mortar. and i want the particles to slide between the bricks and find their way out the top of the diagram.
is my problem that there is no depth to my animation its all paper thin/2d.
the image is face-on skin 'brickwork' with particulars emitter at the bottom of the frame.
i have tried precomping the 'brickwork' and duplicating the layer many times and separating them all by half a pixel z depth, to try give the particles some depth to work with. its not working though.