This PR is a follow up to #64092, which fixed important issues but it was implemented in an overly complex and inefficient way (because it forced the default code path to always go through string operations).
This cleans up all the shader parameter code.
This fixes#54336. Also fixes#56219 because, as the new code never queries the RenderingServer on load, potential deadlocks are avoided.
**NOTE**: materials saved between #62972 and #64092 will no longer work and will need to be resaved in an earlier version.
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.
It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).
We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).
Also fixed "cf." Frenchism - it's meant as "refer to / see".
This makes distance fade look the same regardless of the camera angle,
for all distance fade modes (Pixel Alpha, Pixel Dither, Object Dither).
Distance fade now behaves like fog in this regard.
This allows light sources to be specified in physical light units in addition to the regular energy multiplier. In order to avoid loss of precision at high values, brightness values are premultiplied by an exposure normalization value.
In support of Physical Light Units this PR also renames CameraEffects to CameraAttributes.
`shader_uniform` is now consistenly used across both per-shader
and per-instance shader uniform methods. This makes methods easier
to find in the class reference when looking for them.
This makes the default behavior consistent between SpriteBase3D,
BaseMaterial3D and imported glTF scene materials.
Alpha scissor threshold property hints now allows for more precise
adjustments as well.
Clean up and do fixes to hash functions and newly introduced murmur3 hashes in #61934
* Clean up usage of murmur3
* Fixed usages of binary murmur3 on floats (this is invalid)
* Changed DJB2 to use xor (which seems to be better)
