Corona and Halo Materials

Corona materials make a glowing halo: the soft light that surrounds a star, an eclipse or a magic orb. On its own a corona is not a surface you look at, it is light around something else. You put it on a sphere a little bigger than your core object, and that outer sphere becomes a transparent glow that is brightest right against the core and fades to nothing at its outer edge.

How it works

The halo is drawn from the inside of its shape, using the faces that point away from the camera. For each point the material measures how close the line of sight passes to the center: near the core edge the glow is at full strength, toward the outer outline it falls to zero. The result is a smooth ring of light with no hard border, which is why it reads as atmosphere rather than as a second object.

Three things shape that ring. Falloff sets how quickly the light drops off: low values give a wide, soft halo, high values hold the glow tight against the core. Intensity scales the overall brightness. And the whole halo breathes: its brightness rises and dips on a sine wave, with Pulse Speed setting the tempo and Pulse Amount how deep the dip goes. At a Pulse Amount of zero the glow is steady.

Color is a blend of two values across the ring. Outer Color is the tone where the halo meets the core, Inner Color the tone of the faint outer reach (the names follow the shell, which is seen from the inside). Shell Scale tells the halo how much larger it is than the core, 1.25 meaning a quarter larger, so the brightest part lines up with the core edge. Keep it equal to the size ratio you actually used.

The variants

• Warm suns: Sun Corona is the default amber halo; Solar Flare is wider, brighter and pulses fast.
• Pale and quiet: Eclipse Crown is a pale gold ring with almost no pulse; Frozen Halo is icy blue to white and nearly steady.
• Colored energy: Blue Star in cobalt and cyan, Plasma Wisp in magenta and violet with the fastest pulse, Aurora Veil in emerald and chartreuse.
• Dark and heavy: Hellfire Halo is a tight crimson glow with a slow, deep breath.

How to choose

Match the corona to its core. Over a lava material sphere, pick the halo with the same palette: Sun Corona for Sun Lava, Blue Star for Blue Giant, Hellfire Halo for Hellfire, Plasma Wisp for Plasma Storm. Then decide on the motion. A calm brand scene wants a slow, shallow pulse (Eclipse Crown, Frozen Halo, Aurora Veil); a game or music visual can take the fast, deep pulse of Solar Flare or Plasma Wisp.

The halo also works around non-glowing objects: a dark planet with a thin bright rim reads as an eclipse, and a product model inside a soft halo gets a spotlight-free glow behind it. Adding bloom in post-processing spreads the brightest part of the halo into the scene.