BSTriShape.SetUVs: write to rawUvs (UVs), not rawUVs (tangents)#25
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ousnius merged 2 commits intoousnius:mainfrom Apr 25, 2026
Merged
BSTriShape.SetUVs: write to rawUvs (UVs), not rawUVs (tangents)#25ousnius merged 2 commits intoousnius:mainfrom
ousnius merged 2 commits intoousnius:mainfrom
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BSTriShape has two internal buffers with near-identical names:
rawUVs (capital V) — List<Vector3>, tangent buffer (filled by
UpdateRawTangents)
rawUvs (lowercase v)— List<TexCoord>, UV buffer (filled by
UpdateRawUvs)
SetUVs(...) was resizing/writing to `rawUVs` (the tangent buffer),
silently corrupting tangents on every SetUVs call. The real UV buffer
`rawUvs` was left untouched.
Impact is partial in practice because .Tangents/.UVs accessors
regenerate both buffers from the canonical vertData at read time, so
the sin-set intermediate state was rarely observed, but any code that
read `rawUVs` directly between SetUVs and the next Update* call got
garbage.
C++ nifly avoids the collision with unambiguous names: `rawTangents`
(Geometry.cpp:658) and `rawUvs` (Geometry.cpp:690).
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SetUVshas two write paths that both targetrawUVs(capital V). Per the field comments,rawUVsis the cached tangent buffer (Vector3[]) andrawUvs(lowercase v) is the actual UV buffer (TexCoord[]). The capital-V usage looks like a copy-paste fromSetTangents. UV writes silently mutate the cached tangent list instead.Impact is partially masked because the public
UVsgetter regenerates fromVertexData, but the cachedTangentslist ends up contaminated and any consumer reading it directly sees garbage.C++ reference:
nifly/Geometry.cpp:658(rawTangents) and:690(rawUvs) — the C++ uses unambiguous names that don't collide.Fix: change both write sites to
rawUvs.Maps to issue #15 item F14.