mesh lights

[BVA]

Hi Vladimir

Will we be getting mesh lights in vray/modo any time soon?
I am busy with a scene with LOTS of arches and domes all with lights. currently I am doing light material but mesh lights will be a much better option.

[vladimir.nedev]

I've added a way to create mesh lights for tomorrow's nightly build ( the one from 2016.02.02 ).
You simply connect any mesh to an Area light.



The mesh will be turned into a light with its color/texture/visibility controlled by the Area light item.
The original area light shape (rectangle or ellipse) will not be used.
Once a mesh is connected to an Area light, it will no longer be added as normal geometry to the scene (irrespective of whether the area light is enabled or not).

Greetings,
Vladimir Nedev

[BVA]

Sounds good, thanks Vladimir!!!!

[vladimir.nedev]

Just a note, it's not possible to turn only some of the polygons of a mesh into a light emitter. Also, it's not possible to specify more than one mesh for a single Area light.
So you may have to split/merge your meshes.

Greetings,
Vladimir Nedev

[BVA]

I have used the mesh lights in a few different scenarios today and they seem to work really well. Thanks for adding them!

[Robert]

Oh thats not the best workflow. I was hoping to find a way to replicate lights. Currently use Polygons with illumination. I have no idea how much that would affect render times.

[vladimir.nedev]

Oh thats not the best workflow. I was hoping to find a way to replicate lights. Currently use Polygons with illumination. I have no idea how much that would affect render times.

So, you would prefer to have objects with a V-Ray light material for example be automatically turned into mesh lights ?
Like the "direct illumination" options in the V-Ray Light Mtl in V-Ray for 3ds Max ?

Edit: I didn't read carefully enough, by "replicate", do you mean instance the light emitting geometry with a replicator ?

Greetings,
Vladimir Nedev

[BVA]

Edit: I didn't read carefully enough, by "replicate", do you mean instance the light emitting geometry with a replicator ?

Would this be possible?
I have just done a room with probably 60 odd "ball" lights. Using a replicator to scatter them I cant have a light inside them.

[vladimir.nedev]

Would this be possible?
I have just done a room with probably 60 odd "ball" lights. Using a replicator to scatter them I cant have a light inside them.

Well, MODO doesn't allow light items to be replicated it seems, so that wouldn't be possible.

For normal mesh items that have a V-Ray light material with a future "Direct Illumination" option, it might be possible.
But it will complicate the code quite a bit. Also I am not sure what the effectiveness of this many mesh lights will be versus having them as normal self-illuminated meshes.
I guess it will depend on the size of the light emitting meshes, if they are small enough, it might be worth it to turn them into actual mesh lights.

Greetings,
Vladimir Nedev

[janko22]

When using disconnected polys (lots of ceiling lights) should I put them in one mesh and make it Light Mesh or should I put each ceiling light to it's own mesh and make each one Light Mesh?

[vladimir.nedev]

When using disconnected polys (lots of ceiling lights) should I put them in one mesh and make it Light Mesh or should I put each ceiling light to it's own mesh and make each one Light Mesh?

I am not sure. If you are using probabilistic lights, it feels like separate meshes and thus separate mesh lights will be faster.
But if you are NOT using probabilistic lights, one mesh and thus one mesh light might be faster.

Needs to be tested to be sure.

Greetings,
Vladimir Nedev

[janko22]

Ok, thanks.