Quick answer: Unreal PCG graph using spline input not updating after the spline is moved? Spline change doesn't trigger PCG regen by default - mark the spline component as triggering regen.
Moved a road spline. PCG-placed road segments still follow the old path.
Mark spline as PCG trigger
Spline Component > PCG > Triggers PCG Regeneration = true. Spline edits now invalidate the PCG cache.
Or manually resimulate
Right-click PCG volume > Generate. Forces regen; useful while authoring.
Add a build script
Editor utility blueprint that finds all PCG volumes and regenerates. Run before save to ensure consistency.
“PCG caches inputs. Cached inputs need invalidation triggers.”
Audit which inputs your PCG graphs depend on. Each needs its own regen trigger; the dependency map is the contract.