Quadtree operations. More...

Typedefs
typedef struct _Eina_QuadTree	Eina_QuadTree
	A quadtree is a data structure where each node contains four child nodes. More...

typedef struct _Eina_QuadTree_Item	Eina_QuadTree_Item
	A quadtree item is a holder for (void *) data items inside a quadtree, that includes some state tracking for lifecycle management and optimization purposes.

typedef Eina_Quad_Direction(*	Eina_Quad_Callback) (const void *object, size_t middle)
	Signature for a callback routine used to determine the location of an object within a quadtree. More...

Enumerations
enum	Eina_Quad_Direction { EINA_QUAD_LEFT, EINA_QUAD_RIGHT, EINA_QUAD_BOTH }

Functions
Eina_QuadTree *	eina_quadtree_new (size_t w, size_t h, Eina_Quad_Callback vertical, Eina_Quad_Callback horizontal)
	Constructs a quadtree object. More...

void	eina_quadtree_free (Eina_QuadTree *q)
	Destructs quadtree and its data. More...

void	eina_quadtree_resize (Eina_QuadTree *q, size_t w, size_t h)
	Changes the width and height of the quadtree. More...

void	eina_quadtree_cycle (Eina_QuadTree *q)
	Sets the quadtree's index to 0. More...

void	eina_quadtree_increase (Eina_QuadTree_Item *object)
	Increases the index of the quadtree item by one. More...

Eina_QuadTree_Item *	eina_quadtree_add (Eina_QuadTree q, const void object)
	Inserts a data object into the quadtree. More...

Eina_Bool	eina_quadtree_del (Eina_QuadTree_Item *object)
	Deletes a given quadtree item from the quadtree. More...

Eina_Bool	eina_quadtree_change (Eina_QuadTree_Item *object)
	Marks an object within the quadtree as needing changed. More...

Eina_Bool	eina_quadtree_hide (Eina_QuadTree_Item *object)
	Sets `object` invisible. More...

Eina_Bool	eina_quadtree_show (Eina_QuadTree_Item *object)
	Sets `object` to visible. More...

Eina_Inlist *	eina_quadtree_collide (Eina_QuadTree *q, int x, int y, int w, int h)
	Retrieves items in quadtree inside the target geometry. More...

void *	eina_quadtree_object (Eina_Inlist *list)
	Retrieves the quadtree item's data for the given inline list. More...

Detailed Description

Quadtree operations.

Typedef Documentation

◆ Eina_QuadTree

Eina_QuadTree

A quadtree is a data structure where each node contains four child nodes.

It can be used to partition 2D spaces through subdivision into quadrants.

◆ Eina_Quad_Callback

Eina_Quad_Callback

Signature for a callback routine used to determine the location of an object within a quadtree.

These are used in sorting by determining where in the tree the given data object belongs, using middle as the division line for the two halves of the space.

Function Documentation

◆ eina_quadtree_new()

Eina_QuadTree* eina_quadtree_new	(	size_t	w,
		size_t	h,
		Eina_Quad_Callback	vertical,
		Eina_Quad_Callback	horizontal
	)

Constructs a quadtree object.

Parameters

[in]	w	The geometric width of the quadtree.
[in]	h	The geometric height of the quadtree.
[in]	vertical	The callback for vertical direction determination.
[in]	horizontal	The callback for horizontal direction determination.

Returns: The newly allocated and initialized quadtree, or NULL on error.

The vertical and horizontal callbacks are used to assist in determining which quadrant a given data item belongs to.

References EINA_MAGIC_SET, and EINA_TRUE.

◆ eina_quadtree_free()

void eina_quadtree_free ( Eina_QuadTree * q )

Destructs quadtree and its data.

Parameters

[in] q The quadtree to be freed.

Frees the memory for the Eina_QuadTree object, and any memory used by its change tracking and garbage collection internals.

References EINA_INLIST_CONTAINER_GET, EINA_LIST_FREE, EINA_MAGIC_SET, eina_mempool_free(), and eina_trash_pop().

◆ eina_quadtree_resize()

void eina_quadtree_resize	(	Eina_QuadTree *	q,
		size_t	w,
		size_t	h
	)

Changes the width and height of the quadtree.

Parameters

[in,out]	q	The quadtree to resize.
[in]	w	The new geometric width for the quadtree.
[in]	h	The new geometric height for the quadtree.

Sets the width and height of the quadtree, but the actual update is done lazily.

References EINA_TRUE.

◆ eina_quadtree_cycle()

void eina_quadtree_cycle ( Eina_QuadTree * q )

Sets the quadtree's index to 0.

Parameters

[in,out] q The quadtree to cycle.

◆ eina_quadtree_increase()

void eina_quadtree_increase ( Eina_QuadTree_Item * object )

Increases the index of the quadtree item by one.

Parameters

[in,out] object The quadtree item to increase.

If necessary, records that the root is no longer sorted.

References EINA_FALSE.

◆ eina_quadtree_add()

Eina_QuadTree_Item* eina_quadtree_add	(	Eina_QuadTree *	q,
		const void *	object
	)

Inserts a data object into the quadtree.

Parameters

[in,out]	q	The quadtree to add `object` to.
[in]	object	A data object to store in the quadtree.

Returns: Pointer to the stored quadtree item.

Creates an Eina_QuadTree_Item (or recycles one from the quadtree's trash) and stores the data object in it, then arranges to lazily insert the item into the quadtree (i.e. insertion is delayed until it needs to be used.)

References EINA_FALSE, eina_inlist_append(), EINA_INLIST_GET, EINA_MAGIC_SET, eina_mempool_malloc(), eina_trash_pop(), and EINA_TRUE.

◆ eina_quadtree_del()

Eina_Bool eina_quadtree_del ( Eina_QuadTree_Item * object )

Deletes a given quadtree item from the quadtree.

Parameters

[in] object The quadtree item to be deleted.

Returns: EINA_TRUE on success, EINA_FALSE otherwise.

Moves the item to the quadtree's internal garbage heap for later reclamation.

References EINA_FALSE, eina_list_remove(), EINA_MAGIC_SET, eina_mempool_free(), eina_trash_push(), and EINA_TRUE.

◆ eina_quadtree_change()

Eina_Bool eina_quadtree_change ( Eina_QuadTree_Item * object )

Marks an object within the quadtree as needing changed.

Parameters

[in,out] object The object that has changed.

Returns: EINA_TRUE if change successfully noted, or EINA_FALSE otherwise.

References EINA_FALSE, eina_inlist_append(), EINA_INLIST_GET, and EINA_TRUE.

Referenced by eina_quadtree_show().

◆ eina_quadtree_hide()

Eina_Bool eina_quadtree_hide ( Eina_QuadTree_Item * object )

Sets object invisible.

Parameters

[in,out] object The item within the quadtree to hide.

Returns: EINA_TRUE if object was successfully hidden, or EINA_FALSE if it wasn't in the quadtree.

References EINA_FALSE, and EINA_TRUE.

◆ eina_quadtree_show()

Eina_Bool eina_quadtree_show ( Eina_QuadTree_Item * object )

Sets object to visible.

Parameters

[in,out] object The item within the quadtree to show.

Returns: EINA_TRUE if object was successfully shown, or EINA_FALSE if it wasn't in the quadtree.

References EINA_FALSE, eina_quadtree_change(), and EINA_TRUE.

◆ eina_quadtree_collide()

Eina_Inlist* eina_quadtree_collide	(	Eina_QuadTree *	q,
		int	x,
		int	y,
		int	w,
		int	h
	)

Retrieves items in quadtree inside the target geometry.

Parameters

[in,out]	q	The quadtree to recompute.
[in]	x	New target X coordinate.
[in]	y	New target Y coordinate.
[in]	w	New target width.
[in]	h	New target height.

Returns: The list of collided items or NULL on error.

Forces a rebuild and resort of the quadtree if needed due to pending changes, then performs a collision detection to find items whose geometry is contained within or intersects the given target geometry.

References DBG, EINA_FALSE, EINA_RECTANGLE_SET, EINA_TRUE, and _Eina_Rectangle::w.

◆ eina_quadtree_object()

void* eina_quadtree_object ( Eina_Inlist * list )

Retrieves the quadtree item's data for the given inline list.

Parameters

[in] list The inline list item to lookup

Returns: The contained data object in the Eina_QuadTree_Item, or NULL if none could be found.

References EINA_INLIST_CONTAINER_GET.

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ Eina_QuadTree

◆ Eina_Quad_Callback

Function Documentation

◆ eina_quadtree_new()

◆ eina_quadtree_free()

◆ eina_quadtree_resize()

◆ eina_quadtree_cycle()

◆ eina_quadtree_increase()

◆ eina_quadtree_add()

◆ eina_quadtree_del()

◆ eina_quadtree_change()

◆ eina_quadtree_hide()

◆ eina_quadtree_show()

◆ eina_quadtree_collide()

◆ eina_quadtree_object()