LUMINA GI 2024: True Voxel based Real time Global Illumination

Features:

- Fully real time, true Global Illumination system for the Universal Rendering Pipeline.

- Voxel based solution (Not based on screen space) for zero local change of the lighting or flickering as the camera rotates and moves around.

- No baking or preprocessing of any kind is required. The system is not using SDFs, any kind of scene light or reflection probes and everything is in real time, supporting procedurally changing geometry and worlds.

- Creates a volume representation of the scene, which can be used as a style as well, this aspect will be work in progress for offering a special stylistic voxel look of the whole scene directly. Requires the Standard Built In BiRP pipeline for the voxelization.

- Grabs color from both main color and object textures, for maximum realism.

- Ambient Occlusion embedded to the GI solution.

- Multiple optimizations factors (Full or Half resolution rendering of the effect - Low, High and Insane voxel resolution options - Cones number and lighting calculations steps - Update per a number of seconds or per distance travelled)

- Easy setup, a single script on camera configures the pipeline and the effect directly, minor changes are required in the renderers after that setup, described in the manual and the Video Tutorial.

- Reflections from the voxelized solution.

- Point and spot lights GI as experimetal feature.

- Cascades system that support three cascades each covering a larger part of the world with larger voxel size and one close up for maximizing detail, as experimetal feature.

- Integrated Temporal AA in the RenderGraph version. Two external separate temporal AA solutions are also included in the latest version, that allow lowering a lot the step count.

- Supports big number of mesh shaped lights, mesh lights are configured with emissive color and texture, set HDR color power to zero to stop the effect, above zero to cast light and the main color alpha to further control the light power.

DEMOS:

(Book of the Dead URP with LUMINA and Sky Master volumetric clouds and lighting)

LUMINA new room demo (Windows - Use left CTRL + Mouse to rotate the sun)

(Windows Demo v2.0.4 Optimized Sponza)

(Windows Shroom Reflections Combination Demo)

(Windows Shrooms & Reflections Separate Demos)

Roadmap (Some of the entries are TBD):

- Create combined demos of LUMINA asset together with Sky Master ULTIMATE URP Ethereal Volumetric Lighting system, for a complete atmospheric emulation showcase (Sample image and Video of the first version of the combined assets demo).

IMPORTANT: The real time global illumination problem is generally a very complex and hard one, thus there is some considerations currently on the system, which will be mentioned here.

The system uses Geometry shaders to calculate the voxelized space, thus is not compatible with any hardware that does not support Geometry Shaders, e.g. Mac PCs.

The system is ideal for smaller spaces, where the voxelized space can be calculated only once and possibly be recalculated on the fly every time entering a new room, this is the ideal use scenario.

The system can be used in realtime for infinite worlds with constant space voxelization and there is two ways to optimize, update the voxelization per distance or per time, or both together, keep in mind can be more taxing to get a smoother volume recalculation result in run time.

Update per time will showcase a gap in lighting in moving objects, so is best used for very fast or slow moving items.

The system supports sun light source and local light sources through emissive materials, and there is experimental support for spot and point lights casting GI.

IMPORTANT: The system uses the Standard Pipeline (BiRP) to render the scene voxelized volume when the colorize option is selected, this mode is the most accurate. The rendering is then diverted to the URP. The non colorize mode gives GI which is colored only by the sun light.

In the latest version a fully URP native version is also included as an experimental patch, that does not use the BiRP, this new option does not work in RenderGraph due to Unity downgrading the engine features, and is actively communicated with the Unity team to restore the required features for this mode, such that the system does not depend on the BiRP pipeline eventually.

The true transparent materials are not included in the GI casting, this aspect is work in progress and TBD if can be addressed in later updates.

A cascaded version and integration with volumetric lighting are also in the works, those are both working and are work in progress to finalize, the first cascades version is also included along with relevant demo scenes.

The system requires Unity 2022.3 LTS and above. Due to the complexity and technical methods supports only LTS versions. Also does not support VR, Mobile, Mac because uses Geometry Shaders, WebGL and Consoles. Currently Unity 6 new URP Render Graph pipeline (and Forward, Forward+, Deferred in 2022.3) are supported.

LUMINA GI 2024: Real-Time Voxel Global Illumination