Particular: Color Information from 2D Layer while emitting from OBJ

[Focusfilm.at]

Hi Everyone,

Is it possible, using Trapcode Particular, to emit from OBJ while sourcing the particle color information from a 2D Video Layer?

My exact situation:

• I have two clips shot on a motion Control Setup: V1 = Background + Object,  V2 = just the background. Both have the exact same camera motion.

• I want the effect, that the Object is disintegrating into Particles over the duration of the shot. 

• I have modelled the object roughly in Blender, exported OBJ, tracked the shot in AE and positioned the OBJ in its correct space. I can now emit Particles in the correct position of the object.

• Now i want the Emitted Particles to get their color information from V1 (a 2D Video Layer). Doesn’t sound so hard right? Well, i can’t find the option to do so in Layer Maps…

Can someone please tell me if thats an option (I already fear it is not). Also, I would be very grateful for any suggestions on how you would approach the desired Effect. I already did a passable version without OBJ, where i masked the Object and just did a box emitter with comp size and layer map using the color and alpha from the masked object, but i wanted to have the particles interact with the 3d Camera… 

Thanks!!

[Mylenium · Accepted solution]

That would require

• the OBJ to have proper texture coordinates
• a color texture assigned
• Particular to read the texture value at the emission position

So no, for the time being it can't be done. Perhaps they'll add it in the future in some form. For now you have to settle on full 3D programs for this kind of emission or fake it with other parameters in Particular. Depending on what's actually required a simple gradient layer map with a bit of noise variation might do, but of course that's just speculation. Without seeing your project it will be near impossible to offer concrete advice.

Mylenium

[Focusfilm.at]

Hi Mylenium and thanks as always for the quick and detailed response!,

you confirmed my suspition that this is not yet a feature in Particular. The shot is not for a specific Project, but rather just a test for me... so "faking" the effect is not the goal i tried to achieve. I think i will dive deeper into Blender to see if i can achieve the Effect there.

Thanks again and have a nice Day!,

Niki@Focusfilm