private void ReadVertexNormal() { var parts = SplitLine(); if (parts.Length != 4) { ThrowInvalidModelFormatException("Wrong vertex normal format"); } if (!TryStrictDoubleParse(parts[1], out var x)) { ThrowParseException("vertex normal X"); } if (!TryStrictDoubleParse(parts[2], out var y)) { ThrowParseException("vertex normal Y"); } if (!TryStrictDoubleParse(parts[3], out var z)) { ThrowParseException("vertex normal Z"); } _model.AddVertexNormal(new Vector(x, y, z)); }