Client Library - Rect API

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Detailed Description

s_rect_* api is designed for rectangular operations.

Example:

typical usage of rect api;

 {
        s_rect_t r
        s_rect_t rect r1 = (s_rect_t) {10, 10, 20, 20};
        s_rect_t rect r2 = (s_rect_t) {15, 15, 20, 20};
        if (s_rect_intersect(&r1, &r2, &r)) {
                // no intersection
        }
        // intersectig region is r
 }

 {
        s_list_t *diff;
        s_rect_t rect r1 = (s_rect_t) {10, 10, 20, 20};
        s_rect_t rect r2 = (s_rect_t) {15, 15, 20, 20};

        s_list_init(&diff);
        if (s_rect_difference(&r1, &r2, diff) < 0) {
                // will not happen
        }

        // walk through the difference list
        for (pos = 0; !s_list_eol(list, pos); pos++) {
                s_rect_t *rtmp = (s_rect_t *) s_list_get(list, pos);
                // do what ever you want with the rectangle
                s_list_remove(list, pos);
                s_free(rtmp);
        }

        s_list_uninit(list);
 }

Data Structures
struct	s_rect_s
	rect struct More...
Functions
int	s_rect_merge (s_rect_t *r1, s_rect_t *r2, s_rect_t *r)
	calculates the merging area of r1 and r2.
int	s_rect_intersect (s_rect_t *r1, s_rect_t *r2, s_rect_t *r)
	calculates the intersection area of r1 and r2.
int	s_rect_clip_virtual (s_surface_t *surface, int x, int y, int w, int h, s_rect_t *coor)
	performs clip on rectangle (x, y, w, h).
int	s_rect_clip_real (s_surface_t *surface, int x, int y, int w, int h, s_rect_t *coor)
	performs clip on rectangle (x, y, w, h).
int	s_rect_difference_add (s_list_t *list, int x, int y, int w, int h)
	adds the rectangle (x, y, w, h) to the list
int	s_rect_difference (s_rect_t *r1, s_rect_t *r0, s_list_t *list)
	adds the difference of r1 form r0 to the list

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Function Documentation

int s_rect_clip_real	(	s_surface_t *	surface,
		int	x,
		int	y,
		int	w,
		int	h,
		s_rect_t *	coor
	)

performs clip on rectangle (x, y, w, h).

clip region is the surface's virtual buffer area

Parameters:

	*surface	- surface
	x	- x
	y	- y
	w	- w
	h	- h
	*coor	- on success coor will be the clipped area

Returns:

0 on success, 1 on error.

int s_rect_clip_virtual	(	s_surface_t *	surface,
		int	x,
		int	y,
		int	w,
		int	h,
		s_rect_t *	coor
	)

performs clip on rectangle (x, y, w, h).

clip region is the surface's virtual buffer area

Parameters:

	*surface	- surface
	x	- x
	y	- y
	w	- w
	h	- h
	*coor	- on success coor will be the clipped area

Returns:

0 on success, 1 on error.

int s_rect_difference	(	s_rect_t *	r1,
		s_rect_t *	r0,
		s_list_t *	list
	)

adds the difference of r1 form r0 to the list

Parameters:

	*r1	- rectangle
	*r0	- rectangle
	*list	- list

Returns:

number of differences on success, -1 on error.

int s_rect_difference_add	(	s_list_t *	list,
		int	x,
		int	y,
		int	w,
		int	h
	)

adds the rectangle (x, y, w, h) to the list

Parameters:

	*list	- list to add
	x	- x
	y	- y
	w	- w
	h	- h

Returns:

0 on success, 1 on error.

int s_rect_intersect	(	s_rect_t *	r1,
		s_rect_t *	r2,
		s_rect_t *	r
	)

calculates the intersection area of r1 and r2.

Parameters:

	*r1	- pointer to a rect
	*r2	- pointer to a rect
	*r	- on success r will be the intersection area

Returns:

0 on success, 1 on error.

int s_rect_merge	(	s_rect_t *	r1,
		s_rect_t *	r2,
		s_rect_t *	r
	)

calculates the merging area of r1 and r2.

Parameters:

	*r1	- pointer to a rect
	*r2	- pointer to a rect
	*r	- on success r will be the merging area

Returns:

0 on success, 1 on error.

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