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/****************************************************************************
* graphics/nxglib/nxsglib_rectnonintersecting.c
*
* Copyright (C) 2008-2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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 OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/nx/nxglib.h>
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxgl_nonintersecting
*
* Description:
* Return the regions of rectangle rect 1 that do not intersect with
* rect2. This may be up to founr rectangles some of which may be
* degenerate (and can be picked off with nxgl_nullrect)
*
****************************************************************************/
void nxgl_nonintersecting(FAR struct nxgl_rect_s result[4],
FAR const struct nxgl_rect_s *rect1,
FAR const struct nxgl_rect_s *rect2)
{
struct nxgl_rect_s intersection;
/* Get the intersection of the two rectangles */
nxgl_rectintersect(&intersection, rect1, rect2);
/* Then return the four rectangles representing the regions NON included
* in the intersection. Some of these rectangles may be invalid (zero
* area), but those can be picked off using nxgl_nullrect()
*
* rect1.pt1
* +-------------------------+
* | rect2.pt1 |
* | int.pt1 |
* | +-------------------------+
* | | | |
* | | | |
* +-------------------------+ |
* | rect1.pt2 |
* | int.pt2 |
* +-------------------------+
* rect2.pt2
* rect1.pt1
* +-------------------------+
* rect2.pt1 |int.pt1 |
* +---------+---------------+ |
* | | | |
* | | | |
* | | |int.pt2 |
* | +---------------+---------+
* | | rect1.pt2
* +-------------------------+
* rect2.pt2
* rect2.pt1
* +-------------------------+
* | rect1.pt1 |
* | int.pt1 |
* | +-------------------------+
* | | | |
* | | | |
* | | | |
* +---------+---------------+ |
* | rect2.pt2 |
* | int.pt2 |
* +-------------------------+
* rect1.pt2
*/
result[NX_TOP_NDX].pt1.x = rect1->pt1.x;
result[NX_TOP_NDX].pt1.y = rect1->pt1.y;
result[NX_TOP_NDX].pt2.x = rect1->pt2.x;
result[NX_TOP_NDX].pt2.y = intersection.pt1.y - 1;
result[NX_BOTTOM_NDX].pt1.x = rect1->pt1.x;
result[NX_BOTTOM_NDX].pt1.y = intersection.pt2.y + 1;
result[NX_BOTTOM_NDX].pt2.x = rect1->pt2.x;
result[NX_BOTTOM_NDX].pt2.y = rect1->pt2.y;
result[NX_LEFT_NDX].pt1.x = rect1->pt1.x;
result[NX_LEFT_NDX].pt1.y = intersection.pt1.y;
result[NX_LEFT_NDX].pt2.x = intersection.pt1.x - 1;
result[NX_LEFT_NDX].pt2.y = intersection.pt2.y;
result[NX_RIGHT_NDX].pt1.x = intersection.pt2.x + 1;
result[NX_RIGHT_NDX].pt1.y = intersection.pt1.y;
result[NX_RIGHT_NDX].pt2.x = rect1->pt2.x;
result[NX_RIGHT_NDX].pt2.y = intersection.pt2.y;
}
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