I have this ribbon tire skid effect.
At certain angles, it has the correct thickness.
But at other angles of skidding, it looks thin, like its folding in on itself.
Is there any way to fix this in the emitter settings?
Here are the ribbon settings
What would I need to change to fix this so the car skid marks and applied consistently with consistent width? Many thanks for any possible suggestions!
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the thin/folded look at certain angles is the ribbon strip collapsing: a ribbon is a strip built between consecutive particle positions, its width axis perpendicular to the segment direction. when the skid turns sharply between spawns or the segment runs nearly along the view axis (with camera facing on), the two edge vertices fold toward each other and the width reads as inconsistent. settings that actually address it:
- spawn density is the usual root cause. if you spawn on tick or on a loose distance threshold, fast turning creates long segments between spawns and long segments fold on direction change. spawn per distance traveled instead — a small threshold (every 10-20 cm of wheel travel) — so every ribbon segment is short and curvature is captured.
- camera facing. for ground skids you generally do not want the ribbon facing the camera: at grazing view angles a camera-facing strip visually thins to nothing even though geometry is fine. lay the ribbon flat instead — spawn at the wheel contact point, keep positions on the surface, and check the ribbon renderer facing/UV options so the strip follows the ground plane.
- width drive. make sure width comes from a constant (or a stable curve) and not from something that decays with particle age or position — if the width value scales over the particle lifetime while old particles still define the ribbon tail, the tail visibly tapers. if you want a fade, do it in opacity/color, not width.
- twist and interpolation. zero the twist and raise the ribbon interpolation/tessellation so the strip follows the path smoothly; with too few interpolated points, sharp turns cut corners and self-fold.
if after that you still need absolutely uniform marks, the honest answer is that ribbons are the wrong tool for static skid marks — decal-based or mesh-strip based marks are what production games use, ribbons are for the smoke/spark layer on top. but for a vfx ribbon, 1 + 2 usually fixes most of the inconsistency.
This is likely caused by the ribbon’s facing/orientation. Try a camera-facing or two-sided ribbon mode and check the tangent settings. If the width still changes on sharp angles, a decal or mesh trail may give more consistent skid marks.
