UC2 PC static mesh extraction fixes + OBJ export#339
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- Widen UC2 game detection to ArVer 140-151 (was only 151) to cover PC packages - Split Xbox (ArLicenseeVer=1) and PC (ArLicenseeVer=0) serialization paths in FStaticMeshVertexStream, FRawColorStream, and FStaticMeshUVStream: Xbox streams are guarded by a Flag field, PC streams store data directly - On PC, FStaticMeshVertexStream deserializes vertices one at a time to handle the packed int[3] format used by FUC2Vector/FUC2Normal - LoadExternalUC2Data() is now Xbox-only; PC packages store all geometry inline - Fix FStaticMeshSection::NumFaces on PC: the field holds the last index value, not a face count, so divide by 3 after load - Remove the assert in LoadExternalUC2Data that fired when IndexStream1 was already populated (valid on PC)
On PC (ArLicenseeVer==0) the FPackedPosition serializer writes vertex positions as FVector (3 floats, 12 bytes each) rather than the Xbox int16 triplet (6 bytes). Normals are stored as 3 ints (12 bytes). The previous fix iterated over FStaticMeshVertexUC2 elements one by one which advanced the archive by the right byte count but left V.X/V.Y/V.Z at zero (local read vars were never stored), causing all vertices to collapse to a single deduplicated point in the PSK output. The new PC path bypasses FStaticMeshVertexUC2 entirely and reads directly into FStaticMeshVertex: FVector for position (world-space floats, no GUC2VectorScale/Base transform needed) and int[3] for the normal (consumed but not yet decoded). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
ArVer=140 packages (6 out of 45 UC2 PC static mesh packages) use compact AR_INDEX encoding for export table fields that later versions store as full int32. This matches the FName serialization version threshold already in UnPackage.cpp (ArVer >= 145 uses int32). - UnPackage2.cpp: Serialize2X() now branches on ArVer<145: use AR_INDEX for ClassIndex, SuperIndex, SerialSize, SerialOffset (ArVer>=145 path unchanged - still uses full int32 with int16 truncation) - UnMesh2.h: UC2 PC vertex stream count also stored as AR_INDEX for ArVer<145; use AR_INDEX(Count) when reading vertex count in that path Before: 6 packages failed with "wrong name index" errors because misaligned export table reads produced OOB name indices. After: all 45 UC2 PC static mesh packages export cleanly (2,095 files). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds ExportStaticMeshOBJ() producing .obj + .mtl per mesh LOD, selected via -obj on the command line or the Settings dialog. Per-section material groups are named from UUnrealMaterial names. Targeting UT2004 mod import (raw UE coordinate space, no axis transform). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The 3 ints following each vertex position are float bits, not integer normals. Reinterpret via bitcast. Previously set to (0,0,0). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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UC2 PC static mesh support
Three fixes to extract static meshes from Unreal Championship 2 (PC version, ArVer 140-151):
Fix 1 – Widen UC2 detection range
GameDatabase.cpp: UC2 was only detected at ArVer==151 (Xbox). PC packages use ArVer 140-151, so widened the range to coverboth.
Fix 2 – Split Xbox/PC vertex stream paths
UnMesh2.h: Xbox (ArLicenseeVer=1) has a Flag guard before each vertex array; PC (ArLicenseeVer=0) does not. PC vertexstream reads FVector (3 floats) per vertex, then 3 ints for the packed normal.
Fix 3 – Fix export table and vertex count for ArVer<145 packages
UnPackage2.cpp/UnMesh2.h: Below ArVer=145, ClassIndex/SuperIndex/SerialSize/SerialOffset and TArray counts use AR_INDEXcompact encoding rather than int32. Matches the FName threshold already in UnPackage.cpp.
Also skips LODs with 0 vertices to avoid crashing on
_EMemissive props with no geometry.Tested against all 45 UC2 PC static mesh packages — 2,093 meshes extract cleanly.
OBJ export for static meshes (
-objflag)Adds
ExportStaticMeshOBJ()producing.obj+.mtlper mesh/LOD, selectable via-objon the command line or the StaticMesh format dropdown in Settings. Per-section material groups are named from
UUnrealMaterialnames. Useful for importinginto UE2-era editors (e.g. UT2004 UnrealEd).