Developer Preview 7

Release Notes

Rendering

• New experimental BDPT Fast mode
  A faster bidirectional path tracing variant that skips connecting intermediate vertices while still preserving difficult lighting features like caustics. Provides much lower render times compared to full BDPT with minimal loss of quality.
• Improved BDPT and VCM behavior in complex scenes.
• Improved subsurface scattering handling.
• Improved thin-film, dielectric and principled material behavior.
• Better GLTF material, tangent and transmission support.
• Better environment emitter handling.
• Improved film, pixel sampler and adaptive sampling behavior.
• OIDN denoiser updates.

Scene I/O

• Blender exporter.
• Scene saving.
• Improved GLTF loading: cameras, lights, transforms, materials.

UI / UX

• UI refinements and layout improvements.
• Added opacity, clipping controls and camera export options.
• Better material and emitter parameters exposure.

Assets / Defaults

• Updated test scenes.
• Updated spectrum data and illuminants.

Developer Preview 06

Changes

Rendering

• added random walk subsurface scattering
• changed thin film material tracing logic
• added translucent (diffuse transmission) material
• medium sampling improved
• old an unused materials removed

General changes

• changes to material definition
• overall UI updates and fixes
• material editor greatly improved

Code

• experimental macOS support
• code also compiled with clang on Windows
• old and unused code removed

Developer Preview 05.1

Changes

• subsurface scattering in VCM integrator;
• faster (multithreaded) spatial grid generation in VCM;
• optional support of OpenVDB removed;
• NanoVDB support is now enabled by default ;
• release include binary to convert vbd -> nvdb;
• a lot of code refactoring;
• Embee upgraded to version 4;
• new wavefront CPU path tracer.

Developer Preview 05

Changes

• velvet BRDF;
• subsurface scattering (Christensen-Burley, only available in CPU path tracing integrator);
• all conductor and dielectric are now multi-scattering only;
• all GPU integrators are temporarily disabled;
• RIS sampling in direct lighting integrator (experimental state);
• materials and mediums editing, emitters editing, camera options;
• saving modified scene now available;
• deprecated and unused BRDFs removed;

Developer Preview 04

Changes

• Vertex Connection and Merging integrator working on GPU (super slow, and super long to compile);
• OptiX denoiser could be used on GPU Path Tracer;
• pure CUDA functions now supported (without OptiX);
• various fixes for materials (mixture BRDF works on GPU);
• more test assets included.

Developer Preview 03

Changes

• GPU rendering with OptiX (unidirectional path tracing only now);
• complex Fresnel coefficients (general form);
• thin film rendering on top of all materials (with reflections);
• performance improvements;
• more samples added to assets;
• atmosphere integrator (produces sky environment images).

Developer Preview 02

Changes:

• added Bidirectional integrator;
• added VCM integrator;
• added multiscattering materials;
• added ability to save tonemapped image;
• fixes and improvements in UI and workflow.

Developer Preview 01

The very a first developer preview or etx-tracer:

• basic UI and controls;
• is possible to open .obj files, but materials (.mtl file) have to be adjusted (by default all materials will be diffuse);
• package includes sample scenes (json files), but exact scene format is still to be designed;
• only CPU path tracing is included into this release.