How to copy lights on points in SOP context?

[magneto]

I have a simple dome with some spheres showing the colors of the lights. I am trying to place pointlights at these points so they follow the same points as the spheres. Spheres can be discarded if there is a way to show the object color in the viewport (not light color).

Is there any way to do this? I couldn't do it using the merge sop, etc.

Thanks.

[Macha]

I think you have to instance the lights for this to work. You also need to use a light-template with a light and a shadow shader instead of a standard light from the shelf.

Perhaps it is possible to use PBR as well and make the points emit light that way but I'm not sure how easy it is to get clean results with that.

Other than that...uhmm...point clouds probably but I'm not much of an expert with that method.

[Denis Kozlov]

I have a simple dome with some spheres showing the colors of the lights. I am trying to place pointlights at these points so they follow the same points as the spheres. Spheres can be discarded if there is a way to show the object color in the viewport (not light color).

Is there any way to do this? I couldn't do it using the merge sop, etc.

Thanks.

you can select your spheres, and use geometry light button off the shelf.

points_and_lights.hip

[magneto]

@Macha: I am not sure how to do that.

@Denis: Just tried it and that works but it doesn't show the light effects in the viewport. I just need to show the interactivity of the lights in the viewport.

Is there a way to get the point position of a point? I have 3 separate points, created by the Add SOP and modified by VOPs, but I am not sure how to get each point's position. Then I could reference this in the Transform channels of the lights.

[Denis Kozlov]

@Macha: I am not sure how to do that.

@Denis: Just tried it and that works but it doesn't show the light effects in the viewport. I just need to show the interactivity of the lights in the viewport.

Is there a way to get the point position of a point? I have 3 separate points, created by the Add SOP and modified by VOPs, but I am not sure how to get each point's position. Then I could reference this in the Transform channels of the lights.

You can use render region for example or interactive render for light setup and tuning.

[magneto]

Yeah although for this instance, the end result isn't important. Basically I am just trying to make a prototype of a system in Houdini so I can use Houdini at work.

In the actual system people will also rely on the viewport preview. So that's why I want to get it working using point lights. The viewport preview they give is actually pretty good for this.

So all I need is 3 point lights to follow 3 points in space.

[static]

you could use the point expression:

here's a file with a simple script to attach point lights to points to see it in the viewport. Point instancing lights will still render faster though.

light_populate.hip

[magneto]

Thanks alot static. Will try it when I get home. Rendering speed isn't important for this prototype though.

[static]

Thanks alot static. Will try it when I get home. Rendering speed isn't important for this prototype though.

np, hope it works for you.

[magneto]

I just tried the file, but it says: module object has no attribute populateLights, when I type hou.session.populateLights() into the python shell.

Also there is a python error when I open the file.

Any ideas?

[magneto]

Ok I did it using the point expression. Now it works great

[digitallysane]

Rivet object does it too.

[magneto]

Rivet object does it too.

Thanks, that's a great tool.