API Reference > imodeljs-common > Geometry > GeometryStreamBuilder > appendSubCategoryChange appendSubCategoryChange Method Change SubCategory or reset to SubCategoryAppearance for subsequent geometry. An invalid sub-category id can be supplied to force a reset to the current SubCategoryAppearance. It is not valid to change the sub-category when defining a GeometryPart. A GeometryPart inherit the symbology of their instance for anything not explicitly overridden. appendSubCategoryChange(subCategoryId: string): boolean Parameter Type Description subCategoryId string Returns - boolean Defined in core/common/src/geometry/GeometryStream.ts Line 231 Last Updated: 11 June, 2024