This provides more realistic lighting with a very small performance cost.
The option is available in both GLES3 and GLES2, and can be enabled in
the Project Settings. This goes well with the ACES Fitted tonemapping mode
that was recently added.
When enabled, this also makes upgrading Godot 3.x projects to Godot 4.0 easier,
since lighting in 3.x will better match how it'll look in Godot 4.0.
Higher values will make indirect lighting brighter.
A value of 1.0 represents physically accurate behavior, but higher values
can be used to make indirect lighting propagate more visibly when using
a low number of bounces.
This can be used to speed up bake times by lowering the number of bounces
then increasing the bounce indirect energy. Unlike BakedLightmapData's
energy property, this property does not affect direct lighting
emitted by light nodes or emissive materials.
- Fix Embree runtime when using MinGW (patch by @RandomShaper).
- Fix baking of lightmaps on GridMaps.
- Fix some GLSL errors.
- Fix overflow in the number of shader variants (GLES2).
Completely re-write the lightmap generation code:
- Follow the general lightmapper code structure from 4.0.
- Use proper path tracing to compute the global illumination.
- Use atlassing to merge all lightmaps into a single texture (done by @RandomShaper)
- Use OpenImageDenoiser to improve the generated lightmaps.
- Take into account alpha transparency in material textures.
- Allow baking environment lighting.
- Add bicubic lightmap filtering.
There is some minor compatibility breakage in some properties and methods
in BakedLightmap, but lightmaps generated in previous engine versions
should work fine out of the box.
The scene importer has been changed to generate `.unwrap_cache` files
next to the imported scene files. These files *SHOULD* be added to any
version control system as they guarantee there won't be differences when
re-importing the scene from other OSes or engine versions.
This work started as a Google Summer of Code project; Was later funded by IMVU for a good amount of progress;
Was then finished and polished by me on my free time.
Co-authored-by: Pedro J. Estébanez <pedrojrulez@gmail.com>