From LuxRender Wiki
LuxC4D is a converter plug-in for CINEMA 4D. The latest version is 0.07 which is usable, but nowhere finished. It allows you to export the current camera, lights, 5 channels of C4D standard materials (as long as you don't use shaders), Lux materials, UV texture mapping, portals and it allows you to specify the render settings used for Lux.
A lot of things are missing and will be added in the future as the plug-in is in active development. If you use the current version and get some nice results out of it, the author of the plug-in will be very happy and encouraged which makes working on the plug-in a lot easier ;)
Also as documentation has fallen behind the plugin development any help here would be much appreciated.
The following list covers the recent history of LuxC4D. The plugins can be downloaded from the corresponding release threads, which are:
After downloading the plugin extract it into the plugins folder of CINEMA 4D (usually ../maxon/cinema 4d/plugins) as you would do with any pther C4D plug-in. If you run into trouble, the best place to ask is the LuxC4D forum: http://www.luxrender.net/forum/viewforum.php?f=29
The preferences are quite simple at the moment: You can only specify the path of the LuxRender executable which will be executed when you use "LuxC4D Export + Render". You should set this right in the beginning which makes the workflow a lot easier.
To change the preferences select "Plugins" -> "LuxC4D" -> "LuxC4D Preferences ...". After setting the LuxRender path, click OK and you are ready to go.
Lux tries to automatically convert C4D lights to Lux lights, but this will in most of the cases not work sufficiently as Lux is physically based and unbiased while C4D gives you a lot more artistic freedom, but often quite unrealistic results. This is the conversion table:
- Omni -> Point
- Spot, Square Spot -> Spot
- Infinite, Parallel, Parallel Spot, Square Parallel Spot -> Distant
- Area -> Area
Keep in mind that in Lux all lights have an inverse square falloff.
To give you more control over the exported light and to allow you to specify Lux light types like sun and sky you can assign a LuxC4D Light Tag to it. Changes done there are not changing the rendering of the scene in C4D.
If the scene contains no light, LuxC4D will always export an auto light, even if it's disabled in C4D.
Scene and Render Settings
LuxC4D exports the scene by default using the low discrepancy sampler and path integrator. To let you specify this and a lot more other things, open the C4D render settings dialog and add the post-effect "LuxC4D Scene Settings".
A more detailed description of the render parameters can be found here: LuxRender_Render_settings
As the possibilities of Lux are changing all the time, not all current options are available, but the most important ones can be set there. It's planned to update LuxC4D every now and then to the new options.
The biggest change is the conversion of C4D standard materials to Lux materials. At the moment I export only materials that are not restricted to a polygon selection and of those only the first material of an object. That means if you mix materials or if put different materials over different parts of an object, they will not be exported. At least the automatic splitting of objects into parts with different materials will be implemented in the next release. For now you have to do it manually. Sorry for that.
At the moment the plugin also only supports UV mapping and no shaders. That means you have to do everything with bitmaps and colors.
As the material system of C4D and Lux are quite different, the conversion is also not straight forward and not all effects of Lux are accessible that way and not all possibilities of C4D materials can be converted to Lux. I hope that this first implementation is good enough to start learning Lux and to do some nice renders with C4D scenes.
This is the conversion map from depending on the activation of the C4D material channels "Color" (== "D"), "Transparency" (== "T") and "Reflection" (== "R"): D: The material will become a Lux matte material. If the illumination model is Oren-Nayar, the illumination roughness will be exported as sigma value.
T or T+R or D+T+R: The material will become a Lux glass material, if the dispersion is set to 0, or become a Lux rough glass if the dispersion is set to >0. You will see that mixing reflectivity and transparency works quite different in Lux compared to C4D. There is not much I can do about. The diffuse channel is ignored and not exported.
R: The material will become a Lux mirror material if the dispersion is set to 0 and a shiny metal metal if not. If it's a shiny metal material the reflection channel (Kr) will be turned of and only the specular reflection channel (Ks) will be set .
DR: The material will become a Lux glossy material.
DT: The material will become a Lux matte translucent material. This can be used for some SSS-like effects. The material will look very different in Lux compared to C4D.
If none of these 3 channels is activated or the material is not a standard material, the plugin exports a dummy matte material with the average color of the material.
If at least one of these 3 channels is enabled, and there is also bump enabled, it will be exported, too.
I hope this very short introduction helps you to start using Lux with C4D. If you have questions/problems - feel free to ask. At some point we need to document the plugin. It would be nice if someone else could do that, as my time budget is quite limited (as you already know...). Her you can find some general information about Lux materials: http://www.luxrender.net/wiki/index.php/LuxRender_Materials