modifyExpressions

import { Vrm } from "@hmcs/sdk";

vrm.modifyExpressions(weights) performs a partial update -- only the specified expressions change. Existing overrides not mentioned in the call remain intact.

// First, set happy
await character.modifyExpressions({ happy: 1.0 });

// Later, add a blink without removing the happy override
await character.modifyExpressions({ blink: 1.0 });
// Result: happy=1.0, blink=1.0

tip

Use setExpressions when you want full control over which expressions are overridden. Use modifyExpressions when you want to layer changes without disturbing other overrides.