Tiler
[Data Types]

Data Structures
struct	Eina_Tile_Grid_Info
	Grid type of a tiler. More...
Typedefs
typedef struct _Eina_Tiler	Eina_Tiler
	Tiler type.
typedef struct Eina_Tile_Grid_Info	Eina_Tile_Grid_Info
	Grid type of a tiler.
typedef struct _Eina_Tile_Grid_Slicer	Eina_Tile_Grid_Slicer
Functions
Eina_Tiler *	eina_tiler_new (int w, int h)
	Creates a new tiler with w width and h height.
void	eina_tiler_free (Eina_Tiler *t)
	Frees a tiler.
void	eina_tiler_tile_size_set (Eina_Tiler *t, int w, int h)
	Sets the size of tiles for a tiler.
Eina_Bool	eina_tiler_rect_add (Eina_Tiler *t, const Eina_Rectangle *r)
	Adds a rectangle to a tiler.
void	eina_tiler_rect_del (Eina_Tiler *t, const Eina_Rectangle *r)
	Removes a rectangle from a tiler.
void	eina_tiler_clear (Eina_Tiler *t)
	Removes all rectangles from tiles.
Eina_Iterator *	eina_tiler_iterator_new (const Eina_Tiler *t)
	Create a iterator to access the tilers calculated rectangles.
Eina_Iterator *	eina_tile_grid_slicer_iterator_new (int x, int y, int w, int h, int tile_w, int tile_h)
	Creates a new Eina_Iterator that iterates over a list of tiles.
static Eina_Bool	eina_tile_grid_slicer_next (Eina_Tile_Grid_Slicer *slc, const Eina_Tile_Grid_Info **rect)
	Iterates over the tiles set by eina_tile_grid_slicer_setup().
static Eina_Bool	eina_tile_grid_slicer_setup (Eina_Tile_Grid_Slicer *slc, int x, int y, int w, int h, int tile_w, int tile_h)
	Setup an Eina_Tile_Grid_Slicer struct.

---

Detailed Description

Warning:

This is a very low level tool, in most situations(for example if you're using evas) you won't need this.

Basic usage

Eina_Tiler is a tool to facilitate calculations of which areas are damaged and thus need to be re-rendered. The basic usage of Eina_Tiler is to give it the size of your canvas and a set of rectangular areas that need re-rendering, from that and using heuristics it'll tell you an efficient way to re-render in the form of a set of non-overlapping rectangles that covers the whole area that needs re-rendering.

The following is pseudo-code showing some simple use of Eina_Tiler:

 tiler = eina_tiler_new(MY_CANVAS_WIDTH, MY_CANVAS_HEIGHT);
 EINA_LIST_FOREACH(list_of_areas_that_need_re_rendering, l, rect)
   eina_tiler_add(tiler, rect);
 itr = eina_tiler_iterator_new(tiler);
 EINA_ITERATOR_FOREACH(itr, rect)
   my_function_that_repaints_areas_of_the_canvas(rect);

See also:

eina_tiler_new()

eina_tiler_rect_add()

eina_tiler_iterator_new()

Warning:

There are no guarantees that this will be the most efficient way to re-render for any particular case.

Grid Slicer

Grid slicer and Eina_Tiler are usually used together, that is however not necessary, they can be used independently. Grid slicer provides an easy API to divide an area in tiles which is useful in certain applications to divide the area that will be rendered into tiles. It's customary to, then create one Eina_Tiler for each tile.

The following is pseudo-code showing a very simplified use of grid slicer together with Eina_Tiler:

 itr = eina_tile_grid_slicer_iterator_new(0, 0, MY_CANVAS_WIDTH, MY_CANVAS_HEIGHT, TILE_WIDTH, TILE_HEIGHT);
 EINA_ITERATOR_FOREACH(itr, grid_info)
   {
      tiler = eina_tiler_new(grid_info->rect.w, grid_info->rect.w);
      EINA_LIST_FOREACH(list_of_areas_that_need_re_rendering_in_this_tile, l, rect)
        eina_tiler_add(tiler, rect);
      itr = eina_tiler_iterator_new(tiler);
      EINA_ITERATOR_FOREACH(itr, rect)
      my_function_that_repaints_areas_of_the_canvas(rect);
   }

See also:

eina_tiler_new()

eina_tiler_rect_add()

eina_tile_grid_slicer_setup()

eina_tile_grid_slicer_next()

eina_tile_grid_slicer_iterator_new()

---

Function Documentation

Eina_Tiler* eina_tiler_new	(	int	w,
		int	h
	)

Creates a new tiler with w width and h height.

Parameters:

	w	Width of the tiler
	h	Height of the tiler

Returns:

The newly created tiler

See also:

eina_tiler_free()

References EINA_MAGIC_SET.

void eina_tiler_free

(

Eina_Tiler *

t

)

Frees a tiler.

Parameters:

t

The tiler to free.

This function frees t. It does not free the memory allocated for the elements of t.

void eina_tiler_tile_size_set	(	Eina_Tiler *	t,
		int	w,
		int	h
	)

Sets the size of tiles for a tiler.

Parameters:

	t	The tiler whose tile size will be set.
	w	Width of the tiles.
	h	Height of the tiles.

Warning:

w and h must be greater than zero, otherwise tile size won't be changed.

Tile size is not used!

Eina_Bool eina_tiler_rect_add	(	Eina_Tiler *	t,
		const Eina_Rectangle *	r
	)

Adds a rectangle to a tiler.

Parameters:

	t	The tiler in which to add a container.
	r	The rectangle to be added.

Returns:

EINA_TRUE on success, EINA_FALSE on failure.

See also:

eina_tiler_rect_del()

References EINA_FALSE, and eina_rectangle_intersection().

void eina_tiler_rect_del	(	Eina_Tiler *	t,
		const Eina_Rectangle *	r
	)

Removes a rectangle from a tiler.

Parameters:

	t	The tiler in which to add a container.
	r	The rectangle to be removed.

See also:

eina_tiler_rect_add()

eina_tiler_clear()

References EINA_FALSE, and eina_rectangle_intersection().

void eina_tiler_clear

(

Eina_Tiler *

t

)

Removes all rectangles from tiles.

Parameters:

t

The tiler to clear.

See also:

eina_tiler_rect_del()

Eina_Iterator* eina_tiler_iterator_new

(

const Eina_Tiler *

t

)

Create a iterator to access the tilers calculated rectangles.

Parameters:

t

The tiler to iterate over.

Returns:

A iterator containing Eina_Rectangle.

References EINA_MAGIC_SET, EINA_TRUE, FUNC_ITERATOR_FREE, FUNC_ITERATOR_GET_CONTAINER, and FUNC_ITERATOR_NEXT.

Eina_Iterator* eina_tile_grid_slicer_iterator_new	(	int	x,
		int	y,
		int	w,
		int	h,
		int	tile_w,
		int	tile_h
	)

Creates a new Eina_Iterator that iterates over a list of tiles.

Parameters:

	x	X axis coordinate.
	y	Y axis coordinate.
	w	width.
	h	height.
	tile_w	tile width.
	tile_h	tile height.

Returns:

A pointer to the Eina_Iterator. NULL on failure.

The region defined by x, y, w, h will be divided in to a grid of tiles of width tile_w and height tile_h, the returned iterator will iterate over every tile in the grid having as its data a Eina_Tile_Grid_Info.

Note:

This is a convenience function, iterating over the returned iterator is equivalent to calling eina_tile_grid_slicer_setup() and calling eina_tile_grid_slicer_next() untill it returns EINA_FALSE.

References EINA_ERROR_OUT_OF_MEMORY, eina_error_set(), EINA_MAGIC_SET, eina_tile_grid_slicer_setup(), FUNC_ITERATOR_FREE, and FUNC_ITERATOR_NEXT.

static Eina_Bool eina_tile_grid_slicer_next	(	Eina_Tile_Grid_Slicer *	slc,
		const Eina_Tile_Grid_Info **	rect
	)			[inline, static]

Iterates over the tiles set by eina_tile_grid_slicer_setup().

Parameters:

	slc	Pointer to an Eina_Tile_Grid_Slicer struct.
	rect	Pointer to a struct Eina_Tile_Grid_Info *.

Returns:

EINA_TRUE if the current rect is valid. EINA_FALSE if there is no more rects to iterate over (and thus the current one isn't valid).

This functions iterates over each Eina_Tile_Grid_Info *rect of the grid. eina_tile_grid_slicer_setup() must be called first, and *rect is only valid if this function returns EINA_TRUE. Its content shouldn't be modified.

Note:

Consider using eina_tile_grid_slicer_iterator_new() instead.

static Eina_Bool eina_tile_grid_slicer_setup	(	Eina_Tile_Grid_Slicer *	slc,
		int	x,
		int	y,
		int	w,
		int	h,
		int	tile_w,
		int	tile_h
	)			[inline, static]

Setup an Eina_Tile_Grid_Slicer struct.

Parameters:

	slc	Pointer to an Eina_Tile_Grid_Slicer struct.
	x	X axis coordinate.
	y	Y axis coordinate.
	w	width.
	h	height.
	tile_w	tile width.
	tile_h	tile height.

Returns:

A pointer to the Eina_Iterator. NULL on failure.

The region defined by x, y, w, h will be divided in to a grid of tiles of width tile_w and height tile_h, slc can then be used with eina_tile_grid_slicer_next() to access each tile.

Note:

Consider using eina_tile_grid_slicer_iterator_new() instead.

Referenced by eina_tile_grid_slicer_iterator_new().