Issue
Generated geometry exists but is offset, scaled incorrectly, or does not align with the intended MeshPart.
Cause
Mesh-space vertices, MeshPart size, pivot, and world transform are being mixed.
Fix
Build and inspect the mesh in local space first. Keep the host MeshPart transform stable, calculate bounds, and apply scale once. Do not add world position to every vertex and then also move the MeshPart.
Verify
Generate a simple known triangle or cube at the origin, confirm its bounds, then move only the containing part.
Official Roblox mesh and image API update
#1
Original Heliotrope guidance with authoritative Roblox sources.