LuxCoreRender Forums

heverton wrote: ↑Mon Apr 30, 2018 4:41 pm I think it behaves like this:
Think in a modeled wood floor/planks/and so;
You plug 2 or more textures (Could have a + button to add more then 2);
Randomize by loose geometry and you have only 1 of these textures per loose geometry of the object.

I have no idea what a "loose geometry" is

It sounds like as a single object inside a set of objects and something should be implemented at export time (i.e. BlendLuxCore) and not in the rendering engine

Sharlybg wrote: ↑Mon Apr 30, 2018 1:19 pm After your question i've take more time to think about the mechanics behind ("also found that my first idea was not that good"). The most possible and correct way will be to have it like a sort of advance MIX MATERIAL.

Super MIX MATERIAL

# 1 It should be able to support more than 2 material
# 2 the material will be mixed by blender fonction like : " loose part " " position "

I think it would help if you describe a few different use cases.

I kind of get what you mean though.
It is probably possible to do this with my proposal here:

Access to the object ID in materials (maybe also mapped as floating point in 0..1 range), so we can e.g. scatter 1000 particles and each has a different color, but the same material

Multiple mix materials are already possible, you just have to chain them.
This complexity could be hidden in a BlendLuxCore node.
The object ID 0..1 range would then be plugged into the mix amounts.

See also: http://www.luxrender.net/forum/viewtopi ... de#p125945

Like this:
https://www.cg-source.com/multitexture.php
https://youtu.be/7FmvMbFkh0s?t=58s

B.Y.O.B. wrote: ↑Mon Apr 30, 2018 7:38 pm I think it would help if you describe a few different use cases.

I kind of get what you mean though.
It is probably possible to do this with my proposal here:

Access to the object ID in materials (maybe also mapped as floating point in 0..1 range), so we can e.g. scatter 1000 particles and each has a different color, but the same material

Multiple mix materials are already possible, you just have to chain them.
This complexity could be hidden in a BlendLuxCore node.
The object ID 0..1 range would then be plugged into the mix amounts.

See also: http://www.luxrender.net/forum/viewtopi ... de#p125945

Is it something like Cycles' Object info node > Random, right?
It's very useful to random leaf of a tree and such, my archviz scenes would be very grateful

Is it something like Cycles' Object info node > Random, right?
It's very useful to random leaf of a tree and such, my archviz scenes would be very grateful

Also usefull for wood flooring ! thanks you for helping describe it guys

If possible :

___ Feature to save render without need to stop it !

Dade wrote: ↑Mon Apr 30, 2018 7:16 pmI have no idea what a "loose geometry" is

Loose geometry or loose parts means deatached parts of the same object.
For example a table model (single object) has knee, and legs meshes not connected each other.
I guess he asks for a way to random assign of different input properties to every parts, in the example knee, leg1, leg2, leg3, leg4...
What I don't get in his example is the "Random" checkbox. I think it would be the only option anyway.
And I'm not really sure it's related to the render engine itself, most likely to the exporter.

B.Y.O.B. wrote: ↑Mon Apr 30, 2018 7:38 pmThe object ID 0..1 range would then be plugged into the mix amounts.

If I'm not wrong object ID would be the same for all the loose parts tho cause they are parts of the same object. It works with instances tho.

heverton wrote: ↑Mon Apr 30, 2018 11:02 pmIs it something like Cycles' Object info node > Random, right?

It's useful for many purposes but it still works per object/instance.
BTW, not really related but, I'm very curious if it can be created a random value node with customizable number of outputs, so to have as many random number as we need in one node, for example to create chained mixes.
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While I'm here, I would ask you if currently it's possible in LuxCore prevent lamps from being reflected. I've tried yesterday with an area lamp but I've found only the invisible option which wasn't useful for that. And same question about casting shadows.
If it's not possible, I'd add those as proposed features.
Thanks.

FiatLux wrote: ↑Tue May 01, 2018 8:30 am While I'm here, I would ask you if currently it's possible in LuxCore prevent lamps from being reflected. I've tried yesterday with an area lamp but I've found only the invisible option which wasn't useful for that. And same question about casting shadows.
If it's not possible, I'd add those as proposed features.

Have you tried to use a 100% transparency value for the lamp or a NULL material

Dade wrote: ↑Tue May 01, 2018 10:02 amHave you tried to use a 100% transparency value for the lamp or a NULL material

Premise: I'm using blender, I've forgot to mention it.
Made a quick test, just out of curiosity. The only blender's native lamp which is affected by reflection is Area Lamp.
I haven't found a way to set opacity in Area Lamp, I've found only a checkbox for visibility to camera.

You maybe refer to Mesh Lights where you can assign a emission to matte material and yes, by setting opacity to 0 in matte node I was able to get rid of reflections. I guess I can use mesh lights with 0 opacity instead of area lamps when I need no reflections.
As a side note, for the happiness of many, if you set opacity to 0 you have a tremendous reduction of the fireflies (they are present in both area and mesh lights).

Is there a solution for preventing shadow casting?

FiatLux wrote: ↑Tue May 01, 2018 10:50 am Is there a solution for preventing shadow casting?

No, aside from architectural glass material but it has a very specific purpose. In general, you are not going to find this kind of options in Lux because they are not physically based. Sometime you can use some trick like we were discussing before but, in general, they have always been out of the scope of this project.

Added: "Use a random material for each object in a group (to create a floor with different wood tiles, etc.)"