Mesh Processing
====================

The algorithm allows to modify the mesh by sequentially applying basic processing steps: smoothing, decimation, etc.

Input
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A single mesh.

Output
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None. The input mesh will be modified by the algorithm.

Description
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The following processing options are available to the user:

* **Smooth**: Perform Laplacian smoothing of the mesh. Number of smoothing iterations should be specified in the field **Iterations**.
* **Decimate**: Perform decimation of the mesh. The value in **Max. edge length** sets the constraint on the maximum allowed edge length. The checkbox **Max. surface error** activates a (conservative, yet not guaranteed) upper bound on the maximum distance of vertices in the original mesh to the reduced one. Finally the checkbox **Preserve vertex colors** specifies whether mesh colors should be preserved during the decimation.
* **Color**: Change the color appearance of the mesh. Sliders **Brightness**, **Contrast** and **Gamma** can be used to tune the color appearance of the mesh. Check the **Use HSV color space** checkbox if the HSV color space is preferred.
* **Clean**: Clean the mesh by removing connected components with the specified area. Sliders **Minimum surface area** and **Maximum surface area** determine the range of areas `[minArea, maxArea]`. All connected components, which have the area outside of this range, will be deleted. The button **Select largest component** can be used to automatically select the area range such that only the largest component remains after the cleaning.
* **Crop**: Crops the mesh by removing faces that are outside (or inside if **Discard data inside box** is ticked) of the cropping box. Use manipulators **Translate**, **Rotate** and **Scale** to adjust the cropping box. **Cap hole** can be used to close the holes which resulted from cropping. 
* **Remove edges**: Remove faces that are on the border of the mesh. Value in **Layers** is used to adjust the number of border layers to be removed.
* **Merge close vertices**: Merge close vertices, the distance between which is below the **Threshold**, into one vertex. This option is useful for removing duplicated  vertices.
* **Fill holes**: Fill holes in the mesh by performing Poisson reconstruction.
* **Invert normals**: Invert the direction of mesh vertex normals.
* **Automatic alignment**: Attempt to automatically orient the mesh in such a way that its z-axis is perpendicular to the ground.


The buttons **Undo** and **Redo** can be used to undo and redo the changes made to the mesh. When pressed, the button **Reset** will reset the mesh to its initial state.