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Persona

Rim Light

A light hugging the avatar's outer edge. It separates the subject from the background, and it is the cheapest way to make a model read as sitting in a scene rather than pasted in front of one

It is a screen-space effect, not a fifth scene light. Persona blurs a copy of the frame's coverage alpha and reads it as "how much body lies in this direction", then probes one step toward the light: where that probe lands in the clear is the silhouette, so that is where the glow appears. It therefore does not care where your lights are — only what the avatar's outline looks like

Controls

ControlRangeDefaultEffect
ColorHex#ffffffColour of the rim
Intensity0 – 21How bright the glow is
Ambient0 – 10The undirected share that lights the whole outline
Size1 – 64 px16 pxHow wide the band of light is
Softness0 – 10.6How gradual the falloff is. Low is a thin, crisp edge
Angle0 – 360°45°Which way the light comes from — 0° is straight up, clockwise
Both Sides0 – 10.5How much the backlit side lights up too
Brightness Limit0 – 11The brightest the rim is allowed to push a pixel
Darken0 – 10How far the body itself dims, for contrast

Angle, Both Sides and Ambient

These three decide where the light comes from, and they are what the effect actually sounds like

Angle is the one direction. 0° is straight up and it increases clockwise — 90° from the right, 180° from below, 270° from the left. The default 45° is upper-right, which is where almost every lighting setup starts

Both Sides adds a second rim opposite it. At 1 the two are symmetrical and the whole silhouette is outlined; at 0 only one side lights, which reads more like a real backlight. The default 0.5 keeps the sense of direction without letting the shadow side vanish entirely

Ambient is the undirected share, lighting the whole outline evenly. On its own it reads as a thin halo; mixed into a directional rim it keeps the dark side from disappearing altogether

Brightness Limit and Darken

The rim is screened on rather than added, converging toward Brightness Limit instead of accumulating without bound — so even at full intensity white highlights do not smear into a single blown-out mass. Lower the limit to keep the rim legible over an already bright frame

Darken takes the other route: it dims the body itself, masked to the avatar's own pixels, leaving the background alone. The outline is unchanged but everything inside it drops, so contrast opens up. It is the same trick VTube Studio's backlight uses, and it pays off in dark scenes

Where It Lands

Rim runs after the Live2D layer composites and before chromatic aberration and every colour stage, so the glow grades and blooms as part of the image instead of being a sticker applied last

Because it reads coverage alpha, on the WebGPU engine a Live2D model picks up a rim exactly as a VRM does

Last updated on September 3, 2026

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