Why does my vignette become an ellipse on ultrawide?

Default vignette uses screen UVs which stretch with aspect ratio. Tick Rounded on the URP/HDRP Vignette to ignore aspect and produce a circular falloff regardless of resolution. Or use a custom mask texture authored to your design res.

What are Smoothness and Roundness?

Smoothness controls falloff softness (0=hard edge, 1=very soft). Roundness controls how circular the vignette is (0=elliptical matching aspect, 1=perfect circle). Most games look better with Roundness around 0.7-1.0.

Should I use a custom mask?

For artistic vignettes (heart-shaped border, sniper scope), yes. The Vignette component accepts a Mask texture. Author at your reference resolution; the renderer scales it correctly across screen sizes.

Fix: Unity Post-Process Vignette Stretches on Ultrawide

Quick answer: Tick Rounded on the Vignette override and bump Roundness to 1.0. The vignette is now aspect-independent — circular at 16:9, circular at 21:9, circular at 32:9. For artistic vignettes, use a custom mask texture instead of the procedural one.

Game looks great on a 16:9 monitor. Open it on a 21:9 ultrawide. The vignette’s soft darkening that used to feel cinematic is now an obvious oval. Roundness toggle fixes it in one click.

The Symptom

Vignette renders as an ellipse stretched horizontally on ultrawide displays. On 16:9 it looks circular; on 21:9 wider; on 32:9 alarmingly stretched. The effect feels off-center and visually obvious.

What Causes This

By default, the procedural vignette computes radius from screen UVs (0..1 in both dimensions). On a 16:9 screen the UV space is square in normalized terms but the pixel space is rectangular. The default falloff in UV space produces a shape that follows the screen aspect.

The Fix

Step 1: Rounded checkbox. In your Volume Profile’s Vignette override:

Vignette:
  Mode:        Procedural
  Color:       #000000
  Center:      (0.5, 0.5)
  Intensity:   0.4
  Smoothness:  0.3
  Roundness:   1.0
  Rounded:     true

Rounded = true normalizes the falloff radius to be circular regardless of aspect. Roundness controls the in-between (0 = aspect-matched ellipse, 1 = perfect circle).

Step 2: Adjust Smoothness for soft falloff. 0 = hard edge (rare); 0.2-0.5 = subtle cinematic; 1.0 = very soft.

Step 3: Custom mask if you want a stylized shape.

Vignette:
  Mode:    Masked
  Mask:    M_VignetteShape (Texture2D)
  Color:   #000000
  Opacity: 0.6

The mask is a single-channel texture, white = no vignette, black = fully vignetted. The renderer fits the mask to the screen, scaled by the Volume profile. Author the mask at your design aspect (or square) for best results.

Center Offset

For sniper-scope or wound effects, offset Center from (0.5, 0.5). Combined with high Intensity and tight Smoothness, you get a dramatic peripheral darkening that follows the camera.

Verifying

Toggle Game window resolution between 1920×1080, 2560×1080 (21:9), and 3840×1080 (32:9 simulated). With Rounded on, the vignette stays visually circular. Without, it stretches.

“Rounded on. Roundness 1. Custom mask for artistic shapes. Vignette stays circular at any aspect.”

Related Issues

For Volume effects not applying, see Volume not applying. For Bloom too aggressive, see URP Bloom.

Rounded. Roundness 1. The frame stays cinematic.