Karma renderer

physically-based path tracer renderer

· Karma · Karma (products) Application software · Computer graphics · SideFX Houdini · Karma Sink ·

Description

Karma is Houdini’s physically-based path tracer, which is deeply integrated with USD (it uses USD as its scene description format and acts as a Hydra render delegate). While it shares some concepts with Mantra, Karma is a completely new renderer intended to replace Mantra for new projects.

Karma can render traditional Houdini Object-level scenes that use the Principled shader (either by rendering them directly with the Karma render node or importing them into USD with the Scene Import LOP).

Karma does not support most VEX shading functions (with the exception of certain uses of trace). It does not support VEX geometry/point cloud lookup functions. It does not support material style sheets which are now deprecated.

- Karma XPU takes advantage of both the GPU and CPU simultaneously to ensure full use of all computers resources. This renderer works exclusively with MaterialX shaders. Karma XPU is the faster renderer and is production-ready for a wide range of uses.

- Karma CPU runs entirely in software on the CPU and is able to render both MaterialX shaders and legacy shaders built using VEX. Karma CPU can be used to access the few features not in XPU.

XPU

Karma has two render engines: Karma CPU, which runs entirely in software on the CPU, and Karma XPU, which uses CPU resources and also takes advantage of the GPU and hardware acceleration.

Because it must run in the more limited environment on the GPU, XPU drops support for even more legacy features than Karma CPU. Karma XPU will never support VEX-based shaders at all. Currently it supports the built-in USD materials (such as the USD Preview Surface), and MaterialX, which is probably the future of shading in Karma.

See Karma XPU for more information on limitations and support.