pajammin.util.grid.ProximityGrid

Package pajammin :: Package util :: Module grid :: Class ProximityGrid

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Class ProximityGrid

A container class that organizes objects by their location, based on an attribute whose value is a pygame rect. Each ProximityGrid divides the world into a grid of fixed-sized tiles, and records which tiles each contained object's rect attribute intersects with.

In order to keep the proximity grid up-to-date, it's update method must be called on an object whenever that object's rect-valued attribute is modified.

ProximityGrids are useful because they let us quickly look up all objects that are close to a given point or rect. For more details, see the documentation for the near_point() and near_rect() methods.

Method Summary
	`__init__(self, tile_width, tile_height, rect_attr)` Create a new, empty, `ProximityGrid`.
	`__iter__(self)` Return a list of all objects in the `ProximityGrid`
	`add(self, object)` Add a new object to the `ProximityGrid`.
	`near_point(self, x, y)`
	`near_rect(self, rect)`
	`remove(self, object)` Remove an object from the `ProximityGrid`.
	`update(self, object)`

Method Details

init(self, tile_width, tile_height, rect_attr='rect')
(Constructor)

Create a new, empty, ProximityGrid.

Parameters:: tile_width, tile_height - The width and height of the tiles used to organize objects.; rect_attr - The name of the rect-valued attribute that is used to organize the objects.

iter(self)

Return a list of all objects in the ProximityGrid

add(self, object)

Add a new object to the ProximityGrid. object must define the rect-valued attribute specified in the ProximityGrid constructor to be a pygame rect.

near_point(self, x, y)

near_rect(self, rect)

remove(self, object)

Remove an object from the ProximityGrid.

update(self, object)