Extend HoldLight Example For Particles?

[Atom]

Hi All,

I just ran across the HoldLight example file that ships with Houdini. I like the concept a lot, when the sphere is in a collision state the light turns on.

How would I modify this example for a particle based approach?

I know I can copy the sphere onto the particle points but I am not sure how to include the light template component in that copy and or adjust the CHOP network to work with the possibly of thousands of light copies?

The light template seems to have changed quite a bit since the time when this example was constructed.

sidefx_hold_light_example.hiplc

[Atom]

Here is my basic setup with particles and instancing the Merged Sphere/LightTemplate into a single object. I have the Impact record setup and linked into the CHOP I just don't know how to get the data out of the CHOP and routed to the correct instance?

How do I target particle data out of CHOPs?

chop("../chopnet1/OUT_light_dimmer/WHAT_GOES_HERE:impulse")

ap_multiple_light_hold_1a.hiplc

Edited September 15, 2016 by Atom

[ikoon]

Hello, I am Houdini newbie, so this is probably not a good solution:

a/ you may try to fake it with a "proximity" shader or something like an "ambient occlusion" shader to just fake the light on the surface? That may be fast? I mean:
- get UVs from collision on the surface
- get collision time and subtract the actual time (to avoid the CHOPlag)
- calculate the radius according to the particle distance (bonus)
- make those radiuses additive (something successful here)

b/ why dont you Ray / Copy-Sop lights on the particles and evaluate the same parameters? (collision time/actual time)

Sorry if I am beeing too naive I cannot do a/ nor b/ by myself.

Edited October 27, 2016 by ikoon
EDIT: With your solution, may you COPY points onto particles and target data from the points with Geometry Chop? I am not sure.