This reverts commit 08343189dc.
While the feature is great, a number of issues have been found with the
implementation, and we need more time to resolve them.
So we roll this back for 4.5, to rework the feature for a later Godot
release.
- Revert meshoptimizer patch; the metric used for LOD selection now
incorporates attribute error
- Since LOD selection is now aware of attribute deviation, we don't
need to use a higher normal weight
- To prevent normal creases from creating input triangles with very
large normal deviation, reduce default normal merge threshold
- Since we now use combined metric to select LODs, we never need LODs
with error>1 as these should not be selected if the mesh is visible.
When extracting meshes, materials and animations, always store the uid:// path as well as a res:// fallback.
When validating import settings, load the fallback path if the uid:// path fails to load.
Update save_to_file/fallback_path every import to keep the file path in sync with the uid.
Use UID hashing for meshes and animations.
The old code fetched some data before the `EditorScenePostImportPlugin._pre_process` callback.
While the callback could modify existing keys, this prevented users from adding new data on a fresh import.
By fetching the keys after pre_process, this means users can consistently modify import options for nodes, meshes, materials and animations in a post-import plugin.
This helps, for importers spitting out new resources to the res://
filesystem to actually hash them to generate deterministic UIDs.
This PR also fixes the determinism for translations.
While all the previous fixes to optimizeVertexCache invocation fixed the
vertex transform efficiency, the import code still was missing two
crucial recommendations from meshoptimizer documentation:
- All meshes should be optimized for vertex cache (this reorders
vertices for maximum fetch efficiency)
- When LODs are used with a shared vertex buffer, the vertex order
should be generated by doing a vertex fetch optimization on the
concatenated index buffer from coarse to fine LODs; this maximizes
fetch efficiency for coarse LODs
The last point is especially crucial for Mali GPUs; unlike other GPUs
where vertex order affects fetch efficiency but not shading, these GPUs
have various shading quirks (depending on the GPU generation) that
really require consecutive index ranges for each LOD, which requires the
second optimization mentioned above. However all of these also help
desktop GPUs and other mobile GPUs as well.
Because this optimization is "global" in the sense that it affects all
LODs and all vertex arrays in concert, I've taken this opportunity to
isolate all optimization code in this function and pull it out of
generate_lods and create_shadow_mesh; this doesn't change the vertex
cache efficiency, but makes the code cleaner. Consequently,
optimize_indices should be called after other functions like
create_shadow_mesh / generate_lods.
This required exposing meshopt_optimizeVertexFetchRemap; as a drive-by,
meshopt_simplifySloppy was never used so it's not exposed anymore - this
will simplify future meshopt upgrades if they end up changing the
function's interface.
"Raycast Normals" was introduced in 4.4 dev and defaulted to "false".
The limited testing results at the time suggested that raycasting
generally reduces normal quality compared to native simplifier results,
at the same time increasing vertex memory and import time.
To play it safe, we introduced a setting that defaulted to false, with
the goal of removing it later in 4.4 development cycle if no regressions
are noticed. Since we already had three dev snapshots and no reports,
this change removes the setting and associated code.
"Normal Split Angle" was only used when raycast normals were enabled;
this change removes it from the settings, but keeps it in the script
binding for compatibility.
Existing meshes import exactly the same after this change (unless they
chose to override raycasting which would be surprising).
split_normals helper was only used in this code path and is also removed
for simplicity; it is unlikely that this code will be useful as is, as
it can only regenerate normals without fixing tangents or updating
positions.
