> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/developers/paramml-developer-guide/core-objects/finite-elements-objects/femeshsurface/meshdirection.md).
# MeshDirection
By default, the direction of the mesh is determined by the surface of the polygon. If the surface is not a rectangle, the mesh lines may not be perpendicular. For example, in the figure, the mesh lines are created parallel to the red arrows.
To control the direction of the mesh lines, the MeshDirection parameter can be used. This parameter requires the definition of three points that represent two lines.
For instance, in the FEM1 object, the MeshDirection parameter is set to "\[\[0,0,0],\[1,0,0],\[1,1,0]]", which creates mesh lines that are parallel to the global X and Y axes.
**Example:**
```xml
```
 To view this example in the library, see ()
Please proceed to the next page.
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