BabylonJS/Babylon.js · error · Error

Cannot normalize value ${a}

Error message

Cannot normalize value ${a}

What it means

The Normalize block's _polymorphicNormalize switches on the input's FlowGraphTypes and calls .normalizeToNew() only for supported vector types (Vector2/3/4, Quaternion). Values of any other type — scalars, booleans, matrices, undefined — fall to the default case and throw 'Cannot normalize value ...'. Normalization is only defined for vectors/quaternions in this API.

Source

Thrown at packages/dev/core/src/FlowGraph/Blocks/Data/Math/flowGraphVectorMathBlocks.pure.ts:135

            case FlowGraphTypes.Vector4:
            case FlowGraphTypes.Quaternion: {
                // Normalization is only valid when the length is a positive finite number. For zero, NaN, or
                // +Infinity length the operation is invalid: returning undefined makes the cached base report
                // isValid = false and deliver a zero vector of the same type on `value`.
                const length = (a as Vector3).length();
                if (length === 0 || !Number.isFinite(length)) {
                    if (this.config?.nanOnZeroLength) {
                        // Legacy behavior preserved for consumers that opt into NaN output.
                        const nanVector = a.normalizeToNew();
                        nanVector.setAll(NaN);
                        return nanVector;
                    }
                    return undefined;
                }
                return a.normalizeToNew();
            }
            default:
                throw new Error(`Cannot normalize value ${a}`);
        }
    }

    public override getClassName(): string {
        return FlowGraphBlockNames.Normalize;
    }
}

/**
 * Dot product block.
 */
export class FlowGraphDotBlock extends FlowGraphBinaryOperationBlock<FlowGraphVector, FlowGraphVector, number> {
    constructor(config?: IFlowGraphBlockConfiguration) {
        super(RichTypeAny, RichTypeAny, RichTypeNumber, (a, b) => this._polymorphicDot(a, b), FlowGraphBlockNames.Dot, config);
    }

    private _polymorphicDot(a: FlowGraphVector, b: FlowGraphVector) {
        const className = _GetClassNameOf(a);

View on GitHub (pinned to 0592b347b8)

Solutions

1. Connect a Vector2/Vector3/Vector4 or Quaternion to the Normalize block's input.
2. If you meant to divide a scalar by its magnitude conceptually, that is a no-op for scalars — remove the Normalize block and use the scalar directly (or abs for sign).
3. For matrices, extract row/column vectors first, or construct a vector block upstream before normalizing.

Example fix

// before: number into Normalize -> throws
normalizeBlock.value.connect(scalarOutput); // number

// after: vector input
normalizeBlock.value.connect(directionVectorBlock.output); // Vector3

// before Normalize block runs
function validNormalizeInput(v) {
  return v instanceof BABYLON.Vector2 || v instanceof BABYLON.Vector3 ||
         v instanceof BABYLON.Vector4 || v instanceof BABYLON.Quaternion;
}
if (!validNormalizeInput(normalizeInput)) throw new TypeError('Normalize input must be a vector or quaternion');

function isVectorLike(v): v is BABYLON.Vector2 | BABYLON.Vector3 | BABYLON.Vector4 | BABYLON.Quaternion {
  return v != null && typeof (v as any).normalizeToNew === 'function';
}

try {
  result = normalizeBlock.evaluate(context);
} catch (e) {
  if (e.message.startsWith('Cannot normalize value')) {
    // fall back to identity for non-vectors or log graph wiring bug
    result = normalizeInput;
  } else { throw e; }
}

When it happens

Trigger: Executing FlowGraphNormalizeBlock (_doOperation -> _polymorphicNormalize) when the input connection carries a non-vector value: a plain number, FlowGraphInteger, boolean, string, or Matrix.

Common situations: Wiring a scalar into Normalize expecting per-component division; an upstream block's output type changed from Vector3 to number after refactoring; serialized graph loaded with a default (undefined) input value.

Related errors

• Cannot compute length of value ${a}
• Cannot get dot product of ${a} and ${b}
• Cannot compare ${a} and ${b}
• Cannot get NaN of ${a}
• Cannot get isInf of ${a}

AI-assisted analysis of BabylonJS/Babylon.js@0592b347b8 (2026-08-30). Data as JSON: /api/errors/cf73c85fd14702c9. Report an issue: GitHub.