i just want to know how to get my particles to reference/interact/birth from the surface of the displaced geometry from my displacement shader and not from the actual geo at the SOP level which is obviously not displaced.
thanks

if you are using a picture file for your disp shader then you could apply that to your object as well.
say your using a grid

after you have given it UV coordinates, underneath your uvtexture sop or what ever
add a point sop and in the color parameter use the tex function
tex(“hdisp_geo.jpg”,$MAPU, $MAPV, r)

then in another point sop right beneath it add the $CR to $TY so that $TY is pulled up by the value of the picture at that point
it's like open gl disp map
hope this helps

jacob

very nice jacob, thanks for that. but a slight problem for now is that i am using a procedural displacement shader. how would i do it with this?
thanks again
b

hey betty, u could just make a sop out of your disp. shader (like in the lava training video) and use this one for your particles.

Achim

Yeah, that's the sort of solution you'll need. You can't get around the fact that POPs will need to know the location of a surface at generation time - and displacement maps only happen during rendertime - you can't “intercept” the render displacement when you're running POPs ‘cuz the render isn’t running. :? Somehow, you'll need to cook the displacement into the geo…

Cheers,

J.C.

thanks all.
and yep JC and puma i was thinking of this but was hoping that there was another easier method. i'll give VOPs a spin.
thanks again.
b

i am using a procedural displacement shader. how would i do it with this?

One idea to create a uv texture map from a procedural is to use the mantra -u /obj/model option in H6 in a mantra output driver's render command where /obj/model is pointing at the specific object. First ensure that the geometry has uv texture coordinates. Fork off the chain after the uv's are generated, convert to polys, apply the same shader to your regular geometry and render out.

Still in beta, works with polys only but better than nothing.