Class CostmaQueue

• Defined in File costmap_queue.hpp

Class Documentation

class CostmaQueue

A tool for finding the cells closest to some set of originating cells.

A common operation with costmaps is to define a set of cells in the costmap, and then perform some operation on all the other cells based on which cell in the original set the other cells are closest to. This operation is done in the inflation layer to figure out how far each cell is from an obstacle, and is also used in a number of Trajectory cost functions.

It is implemented with a queue. The standard operation is to enqueueCell the original set, and then retreive the other cells with the isEmpty/getNextCell iterator-like functionality. getNextCell returns an object that contains the coordinates of this cell and the origin cell, as well as the distance between them. By default, the Euclidean distance is used for ordering, but passing in manhattan=true to the constructor will use the Manhattan distance.

The validCellToQueue overridable-function allows for deriving classes to limit the queue traversal to a subset of all costmap cells. LimitedCostmapQueue does this by ignoring distances above a limit.