What you're seeing
Vertex-deformed meshes blur, trail, or reveal a mismatched previous position during motion.
Likely causes
- The material evaluates current WPO parameters for both the current and previous frame.
- Velocity output for vertex deformation is disabled or absent.
- The visible deformation and the recorded motion vector follow different code paths.
Check in this order
- 01Inspect the affected mesh in Motion Blur and Previous Frame Reprojection views.
- 02Confirm that Output velocities due to vertex deformation is enabled in Project Settings.
- 03Use Previous Frame Switch for runtime parameters that change the WPO result.
- 04Test the corrected material at the shipping velocity-pass setting and target frame rate.
Views and commands
Motion vectors
Show VisualizeMotionBlurChecks whether the deformed mesh writes velocity in the expected direction.
Previous-frame reprojection
Show VisualizeReprojectionShows alignment between current detail and the reprojected previous frame.
Material node
Previous Frame SwitchSupplies separate current-frame and previous-frame values to material logic.
Project setting
Rendering > Velocity > Output velocities due to vertex deformationAllows WPO materials to evaluate current and previous positions for velocity.