BabylonJS/Babylon.js · error · Error

Unexpected end of file: missing closing brace

Error message

Unexpected end of file: missing closing brace

What it means

ReadNode consumes lines until it sees a closing "}" for the current node. If the input is exhausted before every opened brace is closed, the recursion cannot terminate cleanly and this error is thrown — the hierarchy section is unbalanced or truncated.

Source

Thrown at packages/dev/loaders/src/BVH/bvhLoader.ts:314

        const numChannels = parseInt(tokens[1]);
        // Skip CHANNELS and the number of channels
        node.channels = tokens.splice(2, numChannels);
        node.children = [];
    }

    // read children
    while (lines.length > 0) {
        const line = lines.shift()?.trim();

        if (line === "}") {
            // Finish reading the node
            return node;
        } else if (line) {
            node.children.push(ReadNode(lines, line, node, context));
        }
    }

    throw new Error("Unexpected end of file: missing closing brace");
}

/**
 * Reads a BVH file, returns a skeleton
 * @param text - The BVH file content
 * @param scene - The scene to add the skeleton to
 * @param assetContainer - The asset container to add the skeleton to
 * @param loadingOptions - The loading options
 * @returns The skeleton
 */
export function ReadBvh(text: string, scene: Scene, assetContainer: Nullable<AssetContainer>, loadingOptions: BVHLoadingOptions): Skeleton {
    const lines = text.split("\n");

    const { loopMode } = loadingOptions;

    scene._blockEntityCollection = !!assetContainer;
    const skeleton = new Skeleton("", "", scene);
    skeleton._parentContainer = assetContainer;

View on GitHub (pinned to 0592b347b8)

Solutions

  1. Count braces: the number of "{" lines must equal the number of "}" lines in the HIERARCHY section — add the missing closing brace(s).
  2. Check the file ends properly: after the hierarchy there should be a MOTION line followed by "Frames: n" and "Frame Time:" then frame data — a file ending mid-tree is truncated; re-download it.
  3. If hand-editing, re-indent the hierarchy (each nesting level inside one more brace) to spot the unclosed block visually.
  4. Validate the file with another BVH reader or the exporting tool before loading it here.

Example fix

// before (missing outer brace)
ROOT Hips
{
  JOINT Spine
  {
    OFFSET 0 8 0
  }
// after
ROOT Hips
{
  JOINT Spine
  {
    OFFSET 0 8 0
  }
}
Defensive patterns

Strategy: validation

Validate before calling

function assertBalancedBraces(text: string): void {
  const hierarchy = text.toUpperCase().split("MOTION")[0];
  const opens = (hierarchy.match(/\{/g) || []).length;
  const closes = (hierarchy.match(/\}/g) || []).length;
  if (opens !== closes) {
    throw new Error(`Unbalanced braces in HIERARCHY: ${opens} open vs ${closes} close.`);
  }
}

Type guard

function hasBalancedBvhHierarchy(text: string): boolean {
  const h = text.toUpperCase().split("MOTION")[0];
  return (h.match(/\{/g) || []).length === (h.match(/\}/g) || []).length;
}

Try / catch

try {
  const skeleton = ReadBvh(text, scene, null, options);
} catch (e) {
  if (e instanceof Error && e.message.includes("missing closing brace")) {
    console.error("BVH hierarchy has an unclosed node block or is truncated.");
  } else { throw e; }
}

Prevention

When it happens

Trigger: A .bvh file with more "{" than "}": a JOINT block missing its final brace, or the entire HIERARCHY section cut off mid-tree before the MOTION keyword; nested joints whose inner braces are balanced but whose outermost ROOT brace is never closed.

Common situations: Files truncated during download or by line-count-limited preview tools; manual edits deleting a "}" line; concatenating a hierarchy with frame data incorrectly so the closing brace is lost; badly written BVH generators.

Related errors

AI-assisted analysis of BabylonJS/Babylon.js@0592b347b8 (2026-08-30). Data as JSON: /api/errors/688cae8c62996ced. Report an issue: GitHub.