This release massively reduces the cost of per pixel probe lighting render path, along with other major improvements. Per pixel is now the default probe lighting method for newly created actors, and replaces per mesh probe lighting. Actors in existing levels that use per mesh probe lighting will continue to do so, but we recommend to switch to per pixel.
Per pixel probe lighting updates that previously ran on the CPU now run in a compute shader on the GPU, reducing the wall clock time by a couple of orders of magnitude. This enables you to increase the maximum probe placement resolution, for more accurate indirect lighting.
Other rendering improvements include:
This release enables extensive use of the Contribute Probe lighting mode across massive worlds, to the same degree as Contribute Lightmap.
The new radiosity implementation for probe lit meshes is accurate, stable and efficient when used at scale. For large meshes with complex organic shapes that are difficult to unwrap, choose the Contribute Probe lighting mode and forget about lightmap UVs.
For large meshes formed of large flat faces or box shapes, Enlighten may still produce the best result with a lightmap.
Enlighten indirect lighting integrates seamlessly with Unreal Engine's real-time ray tracing features. Enlighten is enabled in ray traced effects by default, for a negligible additional shading cost in the same ballpark as Lightmass.
The images below are lit by Enlighten indirect lighting. The image on the left shows ray traced transparency OFF, while the image on the right shows ray traced transparency ON.
We're excited about the new dynamic sky, atmosphere and cloud simulation now available in UE4. This release adds real time Enlighten indirect lighting updates for the Sky Light, making it easy to use a continuously changing time of day in your world. To take advantage of this, simply set up the Sky Atmosphere and enable Real Time Capture for the Sky Light.
This feature is currently experimental. To disable it, set |
In a project with real time ray tracing enabled, dynamic Enlighten shadows are available for Directional Light, Point Light and Spot Light actors. Enable dynamic Enlighten shadows for the sun light source for precise sunlight bounce at any time of day.
The images below are lit by Enlighten indirect lighting. The image on the left shows ray traced Enlighten shadows OFF, while the image on the right shows ray traced Enlighten shadows ON. With ray traced Enlighten shadows, green bounced light is visible where the small patch of bright sunlight illuminates the leaves of the tree.
This release includes optimization of the Enlighten precompute for workstations with many CPU cores. In worlds which use probe lighting extensively, the precompute now makes full use of available CPU resources when many cores are available. On a powerful workstation with 16/32/64 cores, local precomputes finish in significantly less time.
Enlighten automatically places probes to cover an instance of the Enlighten Adaptive Probe Component. While the Enlighten Adaptive Probe Volume actor cannot be placed by a blueprint, the Enlighten Adaptive Probe Component can be added to any actor blueprint.
Enlighten now provides basic indirect lighting for simplified merged proxy meshes created for Hierarchical Level of Detail and World Composition levels. Such meshes do not block or reflect indirect light, but are lit by the Sky Light actor. This works well for proxy meshes that are only ever seen from a long distance.
When running the precompute distributed by SNDBS, tasks are now distributed more effectively to reduce the total time taken.
Warnings are now reported after running the Enlighten parameterize when the Enlighten configuration would generate a very large number of pixels, probes, systems or probe sets. This provides advance feedback so that you can catch problems with the Enlighten configuration before you run the precompute.
Use the new Enlighten Level Stats window to see the estimated number of pixels, probes, systems and probe sets for each level.
The Enlighten visualizations are now available directly from the View Mode menu. This makes it easier to access the visualizations and to switch quickly between them.
The Enlighten Lighting Mode and Lighting Quality view modes now display the Enlighten indirect lighting resolution with a grid pattern. The size of the grid cells matches either the lightmap pixel size for actors with Contribute Lightmap lighting mode, or the adaptive probe resolution for actors with Probe or Contribute Probe lighting mode.
The Enlighten Radiosity Systems and Radiosity Back-faces view modes now display the Enlighten radiosity resolution with a grid pattern. The size of the grid cells matches the Cluster Size associated with the Enlighten Quality configured for the actor.
