+ separate creation of per-part meshes, so per-part approximations can be shared across multiple combine mesh calls
+ split out per-LOD settings of combined meshes to allow more flexbile control of the meshes
#rb David.Hill, Shaun.Kime, benoit.deschenes
#ushell-cherrypick of 35728191 by Jimmy.Andrews
[CL 35934103 by jimmy andrews in ue5-main branch]
[FYI] Jimmy.Andrews
will redo in other stream
Original CL Desc
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new combine mesh interfaces:
+ separate creation of per-part meshes, so per-part approximations can be shared across multiple combine mesh calls
+ split out per-LOD settings of combined meshes to allow more flexbile control of the meshes
#rb David.Hill, Shaun.Kime
[CL 35868104 by jimmy andrews in ue5-main branch]
+ separate creation of per-part meshes, so per-part approximations can be shared across multiple combine mesh calls
+ split out per-LOD settings of combined meshes to allow more flexbile control of the meshes
#rb David.Hill, Shaun.Kime
[CL 35728199 by jimmy andrews in ue5-main branch]
* Reversed index buffers are used to handle negative scaling transforms. Since HLOD meshes will never be used with such transforms, we can get rid of these buffers and reduce memory usage.
#jira UE-216169
#rb JeanFrancois.Dube
[CL 34065502 by sebastien lussier in ue5-main branch]
The FOptions::FilterDecorativePartsLODLevel is too broad and doesn't allow to only remove certain instances of meshes on a specific LOD i.e:. Some meshes can be optimized by replacing multiple mesh instances on lower LOD with a single custom mesh (Atom fake underside optimization).
#jira UE-200222
#rb Ryan.Schmidt
[CL 29689640 by benoit deschenes in ue5-main branch]
* Required for future changes to improve the mesh merging capability to cope with missing/invalid UVs when trying to perform material baking.
#rb ryan.schmidt
[CL 26014245 by sebastien lussier in ue5-main branch]
Add ECoarseApproximationStrategy to IGeometryProcessing_CombineMeshInstances, and FOptions.CoarseLODStrategy, as well as .CoarseApproximationDetailSize (previously was hardcoded to 10 in impelmentation). Rename 'Voxel' to 'Coarse' in the Options struct.
Improve ComputeSweptSolidApproximation in CombineMeshInstancesImpl - 'Square' offset was a chamfer, but generally we want a Miter, with Miter cut threshold set to diagonal length.
Add ComputeBestFullProjectionMesh in CombineMeshInstancesImpl, computes swept-solid approximation along all 3 axes and selects the one w/ lowest geometric deviation
BuildCombinedMesh now supports using SweptPlanarProjection instead of Voxel approximation, or trying both and selecting the one w/ lower geometric deviation.
Disabled coplanar merging and planar retriangulation when doing hidden removal of voxel LODs (was unintentionally doing this)
Update internal usage
#rb none
#preflight 64791efee319748a836e1be5
[CL 25762477 by ryan schmidt in ue5-main branch]
Also tweaked geometric tolerances recently added to RemoveHiddenFaces_ExteriorVisibilit() as they seem to be too aggressive (need to add real-world dimensions here).
Updated internal usage to enable this new capability
#rb none
#preflight 646cea301417daba1e6120a7
#rnx
[CL 25592274 by ryan schmidt in ue5-main branch]
Renamed FInstanceSet to FSourceInstanceList in CombineMeshInstances API
Added FMeshInstanceGroupData.bPreserveUVs flag, defaults to false, in which case UVs are discarded on simplified and approximate meshes to encourage simplification
Added FOptions::MaxAllowableApproximationDeviation, prevents very large deviation in approximation of highly non-convex parts (may break some approximations, might need per-part overrides in future)
Added FOptions::bDoubleSidedHiddenRemoval, treating as single-sided improves hidden removal
FOptions::ApproximationSourceLOD can now be set to a generated simplified LOD, in addition to Source LODs. This helps avoid approximations being higher-quality than simplified parts
In CombineMeshInstancesImpl, renamed FMeshInstanceSet to FMeshPart, FMeshInstance to FMeshPartInstance, FMeshInstanceAssembly to FMeshPartsAssembly, to help clarify internal vs external data structures (many renaming changes as a result)
FPartApproxSelector now has MaxAllowableDeviation, set from new FOptions member, prevents major shape deviation (maybe too strict? might be good to count how many things deviate...)
tweaked AABB-override of approximations based on volume comparison
reduced InitialTriCost scaling for extra approximate LODs in ComputeMeshApproximations - this value is used as an exponent and so if it gets larger than ~5, for large deviations it will basically be infinity and stops being useful. This may need more work as it tends to go to box approximation very quickly now.
Various improvements to RemoveHiddenFaces_ExteriorVisibility. Now can backface-cull, does so by FOptions default. Improved filtering around "glancing angle" rays/hits. Changed from using fixed exterior point set as visibility locations, to direction set. Add slight downscaling of UV triangles, and of hit-triangle barycentric coords, to filter out hits very near to triangle edges, which can often be spurious.
updated internal usage for renaming, set plausible MaxAllowableApproximationDeviation, and using simplified LODs as ApproximationSourceLOD
#rb none
#preflight
[CL 25546006 by ryan schmidt in ue5-main branch]
Add explicit support for Axis-Aligned Box Approximation in addition to existing Oriented Box. Add explicit preference for AABB if it's volume is within 20% of OBB or best-shape approximation.
Other minor fixes.
#rb none
#preflight 64654aedd62884a78f5cbfa9
[CL 25519890 by ryan schmidt in ue5-main branch]
Also added FOptions::VertexColorMappingMode which currently only supports a mapping from tri count (relative to a box) to a white-to-red vertex color scale, basically intended for use as a debug visualization.
#rb none
#preflight 645c13e38e01daf0e5c115f0
#rnx
[CL 25420851 by ryan schmidt in ue5-main branch]
