/*
*Copyright(c)2016, Jeffrey Lee
*Allrightsreserved.
*
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met: 
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef DIRTYRECT_H
#define DIRTYRECT_H

#include <stdbool.h>
#include "areas.h"

/* Dirty rectangle tracking
   Rather than storing a series of rectangles, we represent the area as a series of horizontal slices, with each horizontal slice broken down into a series of vertical slices. Taken together they define the bounds of a rectangle.
   This simplifies the job of merging in new rectangles */

#define DIRTYRECT_X_SLICES 6
#define DIRTYRECT_Y_SLICES 8 /* X slices will be merged automatically, but Y slices won't, so allow for more Y slices than X to try and avoid running out and having to make slices bigger */

typedef struct
{
  int start,end;
} dirtyrect_x_slice;

typedef struct
{
  dirtyrect_x_slice slices[DIRTYRECT_X_SLICES];
  int num;
  int start,end;
} dirtyrect_y_slice;

typedef struct
{
  dirtyrect_y_slice slices[DIRTYRECT_Y_SLICES];
  int num;
} dirtyrect_buffer;

/* Reset/initialise a dirtyrect buffer */
extern void dirtyrect_init(dirtyrect_buffer *buf);

/* Merge 'a' into the list of rectangles */
extern void dirtyrect_add(dirtyrect_buffer *buf, const area *a);

/* Cut 'a' out of 'source' (making that area clean again), storing the intersection of 'a' and 'source' in 'dest' */
extern void dirtyrect_cut(dirtyrect_buffer *source, const area *a, dirtyrect_buffer *dest);

/* Remove a rectangle from 'buf', making it clean again */
extern void dirtyrect_next(dirtyrect_buffer *buf, area *out);

/* Return true if part of 'a' is dirty */
extern bool dirtyrect_intersects(const dirtyrect_buffer *buf, const area *a); 

#endif
