> For the complete documentation index, see [llms.txt](https://gitbook.saf.guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gitbook.saf.guide/structural-analysis-elements/compositeshapedef.md).
# CompositeShapeDef
## Composite Shape Definition
Composite Shape definition is **required** when the cross-section type in [StructuralCrossSection](/structural-analysis-elements/structuralcrosssection.md#cross-section) sheet is set as "General".
For **manufactured** types of a cross-section, is Composite Shape Definition is **optional**, offering the possibility to share detailed shape definition, for better classification of the profile.
### Specification in excel:
| Name of the column header | Type of data | Value example or enum definition | Required value | Description |
| ------------------------- | ------------ | :---------------------------------------------------: | ------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Name | String | GEN\_1 | yes | Name of the profile from the [StructuralCrossSection](/structural-analysis-elements/structuralcrosssection.md#cross-section) object sheet |
| Material name # | String | MAT\_1 | yes, if polygon is not opening | Name reference to the existing [StructuralMaterial](/structural-analysis-elements/structuralmaterial.md#material) object |
| Polygon contour # | String | -75.0; 105.0\| -175.0; 5.0\| 175.0; 5.0\| 75.0; 105.0 | yes (at least one) | This attribute is used to define the cross-section geometry as a polygon contour.
One cross-section shape can consist of more polygons.
Openings contour are defined clockwise.
Common polygons counterclockwise.
The format of the data is:
y1; z1
|
| Id | String | 39f238a5-01d0-45cf-a2eb-958170fd4f39 | no | Unique attribute designation |
## Notes
{% hint style="info" %}
The symbol "#" means indexing of the name columns, depends on how many polygons is used, starts from 1
The contour defined clockwise is opening
The contour defined counter clockwise is polygon of the general cross-section (relation between LCS and counter clockwise direction is shown below)
{% endhint %}
{% hint style="info" %}
Each polygon has a defined material which is name reference to existing material in [StructuralMaterial](/structural-analysis-elements/structuralmaterial.md#material) sheet
* The opening has no material definition
* Each polygon contour has to be closed
* The set of all polygons and openings defines one general cross-section (one row in the Excel table)
* The number of polygons is limited to 99. The definition of the general shape has to consist of at least one polygon which is not the opening.
* CompositeShapeDef example with opening is shown below. A,B,C,D are defining the contour of cross-section (counter clockwise polygon) and E,F,K,L are defining the opening (clockwise polygon).
{% endhint %}
