Supported Cinema 4D features

In order to render a Cinema 4D scene using a Thea engine, the Cinema 4D objects have to be converted into Thea objects.

Geometry Conversion
All of Cinema 4D’s geometries should be converted out of the box. Polygon objects, primitives, generators, instances and render instances are translated into Thea objects (models and proxies). There are some objects though such as hair that their generated geometry is depending on the current frame. In this case, please enable the "Execute Preceded Passes" in Thea's Render Settings.

Camera Conversion
A Cinema 4D camera object is converted into Thea Camera. The parameters that are currently supported are projection, focal length, film offset, focus distance, near/far clipping, sensor size and zoom (in case of parallel projection). Regarding the projections, only Perspective and Parallel are available from Cinema4D to Thea. To extend Cinema 4D camera with Thea features (such as extra projection options), one has to apply a Thea Camera tag to it.

Material Conversion
Cinema4D materials are converted automatically into Thea materials before transferred to Thea's rendering engine. Due to differences in the material system, the conversion is taking place using heuristic rules. That means there are some features/parameters in C4D materials that are not supported in Thea ones and vice versa.
The following channels are supported: Color, Diffusion, Specular, Reflection, Transparency, Bump, Alpha, Luminance, Fog and Displacement.

  • Color or Diffusion: A Basic BSDF will be created with the diffuse parameter enabled.
  • Color: If Oren-Nayar is used as illumination model, its value will be copied in Basic's sigma parameter.
  • Color + Diffusion: if they are both enabled, a combined Thea XML texture will be created and used in Basic Diffuse parameter.
  • Specular: Each reflection layer (max 3) is converted into a Basic BSDF with reflectance enabled. Thea's IOR, Roughness and K parameters are calculated based on C4D reflectance's width, falloff, inner width and specular strength parameters.
  • Reflection (prior to R16): It's converted into Coating with IOR 3.5. Blurriness is copied to roughness.
  • Transparency: A Glossy BSDF with transmittance will be created. Absorption value, absorption color and Index Of Refraction (IOR) are copied to the corresponding parameters. Blurriness is copied to Glossy's roughness
  • Luminance: A Thea material with emittance component will be created. Thea emittance will have Power 100 watts and Efficacy 20 (lm/w). If generate GI is disabled in C4D's luminance's channel, Thea's emittance passive emitter parameter will be enabled.
  • Alpha: A Thea material with clipping (Alpha) component will be created. Soft and Invert parameters are preserved.
  • Fog: A Thea material with Medium will be created. Fog's distance will be translated into Absorption Density. Also, Isotropic will be used as phase function.
  • Bump/Normal: If any of Bump or Normal channel is enabled, the bump (or normal) channel is copied to each bsdf's bump parameter. If Bump channel is enabled, the Normal channel will not be taken into consideration. If normal is enabled and bump isn't, the "Normal Map" of each BSDF will be enabled.
  • Displacement: Cinema4D’s displacement parameters will be copied to Thea Material’s Displacement component. Height, Texture and Subdivision Level will be copied to the corresponding parameters in Thea’s Material.

In any case, the color and the texture parameters are preserved unmodified (only for the channels described above). Brightness range value is [0,100], since it is multiplied with the color.
The shaders that are supported in Thea materials are Color, Bitmap, Color Mograph and any procedural that operates in UV coordinates. To handle the procedurals, a Thea material applies Texture Baking on them. This procedure generates a bitmap based on the shader, which can be used later in Thea's render engine as bitmap texture. Texture Baking can be parameterized either from the "Bake" tab in Render Settings or via a Thea Bake Tag.

Light Conversion
Cinema 4D light objects are converted into Thea light objects. The supported parameters are color, brightness, light type, shadow type, falloff, photometric units, photometric intensity and photometric data (IES). To convert a light into sun without using a Thea Sun Tag, select an infinite, distant, parallel or square parallel light type. In order to make the sun visible, select “Shadow Maps (Soft) as shadow type.

Interactive Rendering
Cinema 4D’s own interactive render region is supported. Nevertheless, it invokes production rendering from Thea Render's side. To employ Interactive Rendering (IR) in Thea Render, you have to use the Darkroom. While IR runs, any object change is converted solely and transferred anew into the engine.
While this works for most of tweaks (Materials, Render Settings, Display Settings, etc.), hierarchy changes cause full retransfer of the scene.

Team Render
Team Render is supported by the integrated plugin but only for animations where each client processed a full frame. Co-operative rendering on the same frame using Team Render is not supported; currently, you can only use Thea Render’s network rendering for co-operative rendering on still images. If you are about to render via Team Render, use relative paths in resources (textures, hdr), otherwise if the absolute path is not valid in the client, the resources won't be found.