Tizen Native API  6.0
Functions | Typedefs
Quadtrees
Data Types

Quadtree operations.

Functions

Eina_QuadTree * eina_quadtree_new (size_t w, size_t h, Eina_Quad_Callback vertical, Eina_Quad_Callback horizontal)
 Constructs a quadtree object.
void eina_quadtree_free (Eina_QuadTree *q)
 Destructs quadtree and its data.
void eina_quadtree_resize (Eina_QuadTree *q, size_t w, size_t h)
 Changes the width and height of the quadtree.
void eina_quadtree_cycle (Eina_QuadTree *q)
 Sets the quadtree's index to 0.
void eina_quadtree_increase (Eina_QuadTree_Item *object)
 Increases the index of the quadtree item by one.
Eina_QuadTree_Item * eina_quadtree_add (Eina_QuadTree *q, const void *object)
 Inserts a data object into the quadtree.
Eina_Bool eina_quadtree_del (Eina_QuadTree_Item *object)
 Deletes a given quadtree item from the quadtree.
Eina_Bool eina_quadtree_change (Eina_QuadTree_Item *object)
 Marks an object within the quadtree as needing changed.
Eina_Bool eina_quadtree_hide (Eina_QuadTree_Item *object)
 Sets object invisible.
Eina_Bool eina_quadtree_show (Eina_QuadTree_Item *object)
 Sets object to visible.
Eina_Inlist * eina_quadtree_collide (Eina_QuadTree *q, int x, int y, int w, int h)
 Retrieves items in quadtree inside the target geometry.
void * eina_quadtree_object (Eina_Inlist *list)
 Retrieves the quadtree item's data for the given inline list.

Typedefs

typedef struct _Eina_QuadTree Eina_QuadTree
typedef struct _Eina_QuadTree_Item Eina_QuadTree_Item
typedef Eina_Quad_Direction(* Eina_Quad_Callback )(const void *object, size_t middle)

Typedef Documentation

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.

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_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.

Function Documentation

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

Inserts a data object into the quadtree.

Parameters:
[in,out]qThe quadtree to add object to.
[in]objectA 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.)

Since :
3.0
Eina_Bool eina_quadtree_change ( Eina_QuadTree_Item *  object)

Marks an object within the quadtree as needing changed.

Parameters:
[in,out]objectThe object that has changed.
Returns:
EINA_TRUE if change successfully noted, or EINA_FALSE otherwise.
Since :
3.0
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]qThe quadtree to recompute.
[in]xNew target X coordinate.
[in]yNew target Y coordinate.
[in]wNew target width.
[in]hNew 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.

Since :
3.0
void eina_quadtree_cycle ( Eina_QuadTree *  q)

Sets the quadtree's index to 0.

Parameters:
[in,out]qThe quadtree to cycle.
Since :
3.0
Eina_Bool eina_quadtree_del ( Eina_QuadTree_Item *  object)

Deletes a given quadtree item from the quadtree.

Parameters:
[in]objectThe 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.

Since :
3.0
void eina_quadtree_free ( Eina_QuadTree *  q)

Destructs quadtree and its data.

Parameters:
[in]qThe quadtree to be freed.

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

Since :
3.0
Eina_Bool eina_quadtree_hide ( Eina_QuadTree_Item *  object)

Sets object invisible.

Parameters:
[in,out]objectThe item within the quadtree to hide.
Returns:
EINA_TRUE if object was successfully hidden, or EINA_FALSE if it wasn't in the quadtree.
Since :
3.0
void eina_quadtree_increase ( Eina_QuadTree_Item *  object)

Increases the index of the quadtree item by one.

Parameters:
[in,out]objectThe quadtree item to increase.

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

Since :
3.0
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]wThe geometric width of the quadtree.
[in]hThe geometric height of the quadtree.
[in]verticalThe callback for vertical direction determination.
[in]horizontalThe 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.

Since :
3.0
void* eina_quadtree_object ( Eina_Inlist *  list)

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

Parameters:
[in]listThe inline list item to lookup
Returns:
The contained data object in the Eina_QuadTree_Item, or NULL if none could be found.
Since :
3.0
void eina_quadtree_resize ( Eina_QuadTree *  q,
size_t  w,
size_t  h 
)

Changes the width and height of the quadtree.

Parameters:
[in,out]qThe quadtree to resize.
[in]wThe new geometric width for the quadtree.
[in]hThe new geometric height for the quadtree.

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

Since :
3.0
Eina_Bool eina_quadtree_show ( Eina_QuadTree_Item *  object)

Sets object to visible.

Parameters:
[in,out]objectThe item within the quadtree to show.
Returns:
EINA_TRUE if object was successfully shown, or EINA_FALSE if it wasn't in the quadtree.
Since :
3.0