Reference/Release Notes/2.81/Cycles

Blender 2.81: Cycles

Denoising

A new Denoise node was added in the compositor, to denoise renders using OpenImageDenoise. It needs Albedo and Normal passes, which Cycles can render by enabling Denoising Data passes.

This feature requires a CPU with SSE4.1, available in Intel and AMD CPUs from the last 10 years.

Shaders

Shader nodes for Cycles and Eevee have been extended.

  • New White Noise Texture node, producing a random number based on input values. (133dfdd7)
  • Noise Texture node: support 1D, 2D, and 4D noise. (23564583)
  • Musgrave Texture node: support 1D, 2D, and 4D musgrave. (f2176b3f)
  • Voronoi Texture node: support 1D, 2D, and 4D voronoi. Add more feature types. (613b37bc)
  • New Volume Info node, for convenient access to Color, Density, Flame, and Temperature attributes of smoke domains. (e83f0922)
  • Object Info node: new Object Color output. (08ab3cbc)
  • New Map Range node. Linearly remap a value from one range to another. (71641ab5) (7a7eadaf)
  • New Clamp node. Clamps a value between a maximum and a minimum values. (313b7892)
  • Math node: shows one or two inputs depending on how many are needed by the operation. (e5618725)
  • Vector Math node: new operations, and show number of inputs depending on the operation. (7f4a2fc4)
  • Mapping node: location, rotation and scale are now node inputs that can be linked to other nodes. (baaa89a0bc5)
  • New Vertex Color node, for convenient access to Vertex Colors and their alpha channel. (2ea82e86)
New voronoi texture nodes

NVIDIA RTX

Cycles now has experimental support for rendering with hardware-accelerated raytracing on NVIDIA RTX graphics cards. This is done by enabling Optix in Preferences > System > Cycles Render Devices.

This does not support all features in the CUDA backend yet. Currently still missing are baking, branched path tracing, ambient occlusion and bevel nodes, using CPU memory, and combined CPU + GPU rendering.

Optix requires recent NVIDIA drivers, and is supported on Windows and Linux.

  • Windows: driver version 435.80 or newer
  • Linux: driver version 435.12 or newer

When rendering the first time, the Optix kernel needs to be compiled. This can take up to a few minutes.

Optix performance compared to CPU and CUDA

The Optix backend was contributed by NVIDIA.

Adaptive Subdivision

Cycles adaptive subdivision now stitches faces to avoid cracks between edges, that may be caused by displacement or different materials.

Cycles displacement cracks.jpg
Adaptive subdivision with and without cracks

Other

  • Reduced shadow terminator artifacts for bump mapping with diffuse BSDFs.
Before
After
  • Viewport support to use HDRI lighting instead of scene lighting, for look development.
  • Viewport option to display a render pass, instead of the combined pass.