- Two-dimensional dithered sampling: most samplers (e.g. soft shadows, indirect illumination, depth of field) will now take advantage of dithered sampling, which improves the visual distribution of noise specially at low sample rates.
- Quad lights: a new sampler has been developed that reduces noise for surface lighting, specially especially in unoccluded regions. For debugging and for comparisons with the previous sampler, the global options.enable_new_quad_light_sampler can be disabled (this control will be removed in a future update).
- Cylinder lights: sampling has been improved, significantly reducing noise inside volumes or where cylinder lights are located near other surfaces.
- Disk lights: a novel sampling algorithm has been implemented for disk lights which can greatly improve their rendering quality when shading points near the disk's surface, particularly in volumes.
- Russian roulette: on average better performance for hair, transmission and volume scattering.
- Caustic noise reduction: a new method was added to reduce noise from caustics. The global option indirect_specular_blur controls the trade-off between more accurate noisy renders at 0.0, and more blurry biased renders with reduced noise at higher values.
- Faster opacity mapping: opacity-mapped transparent surfaces, such as tree leaves, are now sampled more efficiently and can render up to 20% faster, specially in machines with many threads.