Tachyon renderer pro — OVITO User Manual 3.7.5 documentation

# Tachyon renderer pro

This is a software-based ray-tracing renderer. It can produce renderings of the scene with ambient occlusion lighting, shadows and depth of field. The visual quality of the Tachyon renderer is slightly better than the one provided by the OSPRay renderer, but it requires more memory. Both rendering engines offer higher visual quality than the OpenGL renderer, but are typically considerably slower.

## Parameters

Anti-aliasing samples

  To reduce aliasing effects, the Tachyon ray-tracer can perform supersampling by computing multiple rays per output pixel. This parameter controls the number of rays.

Direct light

  Enables the parallel light source, which is directed from an angle behind the camera.

Shadows

  Enables cast shadows for the directional light. Not that, with the current Tachyon version, you cannot turn off shadows when ambient occlusion shading is enabled. In this case, you can only turn off the directional light source completely.

Ambient occlusion

  Enabling this lighting technique mimics some of the effects that occur under conditions of omnidirectional diffuse illumination, e.g. outdoors on an overcast day.

Sample count

  Ambient occlusion is implemented using a Monte Carlo technique. This parameters controls the number of samples to compute. A higher sample number leads to a more even shading, but requires more computation time.

Depth of field

  This option enables depth-of-field (DOF) rendering, which blurs objects that are not in the focus of the camera. Note that depth-of-field rendering only works for viewports with a perspective projection! Furthermore, anti-aliasing must be enabled for DOF to work and the number of anti-aliasing samples affects the quality of the blurring.

Focal length

  This parameter sets the focus distance of the camera. Only objects at this distance from the camera will appear sharp when depth-of-field rendering is active. Objects closer to or further from the camera will appear blurred. If you want a specific object to be in the focus, use the Pick in viewport button and click on that object in the viewport to be rendered. The focal length parameter will be automatically adjusted so that the picked location is in focus.

Aperture

  The aperture of the camera. This parameter controls the strength of the depth-of-field effect, i.e., how much objects are blurred that are out of focus.

See also

`TachyonRenderer` (Python API)