Instanced Static Meshes?

[SneakySoft]

How do instanced static meshes work?
In the Materials Compendium @ the PerInstanceRandom node:

"This only works when applied to an InstancedStaticMesh Actor".

It indeed doesn't work on a regular static mesh,
so how do I get it from a StaticMesh to an InstancedStaticMesh?

[Wyldhunt]

It was talked about briefly here, begining with post #5:
http://forums.epicgames.com/showthread.php?t=745033

The only mesh I've found that are considered 'Instanced' are procbuildings. So, I guess it exists only for procbuildings?

[SneakySoft]

That would be strange since the PerInstanceRandom node was there before ProcBuildings existed. I know ProcBuildings can make use of this node but there should be more actors able to use it.

[Wyldhunt]

If you find any, let me know.
It seems that the instanced meshes that it refers to are meshes that are dynamically instanced by the engine. Similar to procbuildings and foliage... except it doesn't work on foliage.

[SneakySoft]

Has anyone ever used this node before, please explain it's purpose and if/how I can use it with meshes?

[billysson]

If you have a mesh placed in the scene, and you alt+drag to copy it, that is an instance of the mesh, rather than a copy, is it not?

[Wyldhunt]

It was implied that it worked on meshes that were dynamically instanced by the engine such as proc buildings.
There is an option in the Mesh Properties named something like "Used With Instancing". Checking that box would be a good start. I don't know if you then need to make the engine dynamically instance it or if the fact that you've marked it as an instanced mesh in the properties is enough. I haven't checked.

[Spoondog]

Another way to get a random number 0-1 per static mesh in the material editor:

Frac ( (ObjectWorldPosition.X + ObjectWorldPosition.Y) / 100 )

[SneakySoft]

Another way to get a random number 0-1 per static mesh in the material editor:

Frac ( (ObjectWorldPosition.X + ObjectWorldPosition.Y) / 100 )

True, but then the number will change when the object is moved, like for example with physics.

It was implied that it worked on meshes that were dynamically instanced by the engine such as proc buildings.
There is an option in the Mesh Properties named something like "Used With Instancing". Checking that box would be a good start. I don't know if you then need to make the engine dynamically instance it or if the fact that you've marked it as an instanced mesh in the properties is enough. I haven't checked.

I did check that box, isn't doing anything different for me.