Polygon Sort¶

https://user-images.githubusercontent.com/14288520/188287885-e2b96646-045e-41ee-888c-7c85eff0b3df.png

Functionality¶

Polygon Sort node sorts the input polygons by various criteria: distance, area and normal angle.

Inputs¶

All parameters except Mode and Descending are vectorized and can take single of multiple input values.

Parameters¶

All parameters except Mode and Descending can be given by the node or an external input.

Param	Type	Default	Description
Mode	Enum	“D”	The sorting direction mode: P : Sort by the the distance to a point P D : Sort by the projection along a direction D A : Sort by the area of the polygons ND : Sort by the normal angle relative to direction D NP : Sort by the normal angle relative to point P
Descending	Bool	False	Sort the polygons in the descending order.
Verts	Vector	none	The vertices of the input mesh to be sorted.
Polys	Polygon	none	The polygons of the input mesh to be sorted.
Point P	Vector	(1,0,0)	The reference vector: Point P. [1]
Direction	Vector	(1,0,0)	The reference vector: Direction D. [1]

Notes: [1] : “Point P” is shown in P and NP mode and “Direction” is shown in D and ND mode. These are used for distance and normal angle calculation. The area mode (A) does not use the input sorting vector.

Outputs¶

Indices : The indices of the sorted polygons.
Vertices : The input vertices.
Polygons : The sorted polygons.
Quantities : The quantity by which the polygons are sorted. Depending on the selected mode the output quantities are either Distances, Projections, Angles or Areas.

Note: The output will be generated when the output sockets are connected.

Modes¶

The modes correspond to different sorting criteria and each one has a quanitity by which the polygons are sorted.

Point (P) : In this mode the polygons are sorted by the distance from the center of each polygon to the given point P.
Direction (D) : In this mode the polygons are sorted by the projection component of polygon center vector along the given direction D.
Area (A) : In this mode the polygons are sorted by the area of the polygons.
Normal Angle Point (NP) : In this mode the polygons are sorted by the angle between the polygon normal and the vector pointing form the center of the polygon to the given point P.
Normal Angle Direction (ND) : In this mode the polygons are sorted by the angle between the polygon normal and the given direction vector D.

Presets¶

The node provides a set of predefined sort directions: along X, Y and Z. These buttons will set the mode to “D” and the sorting vector (Direction) to one of the X, Y or Z directions: (1,0,0), (0,1,0) and (0,0,1) respectively. The preset buttons are only visible as long as the sorting vector socket is not connected.

References: The algorithm to compute the area is based on descriptions found at this address: http://geomalgorithms.com/a01-_area.html#3D%20Polygons (not available)

https://web.archive.org/web/20210421151955/http://geomalgorithms.com/a01-_area.html (see Polygons)