gui__intersectrect.c

来自「uCGUI」· C语言 代码 · 共 38 行

/*************************************************************************************************************
                                                   uC/GUI
                                               嵌入式通用图形软件
File        : GUI_IntersectRect.c
Purpose     : Implementation of GUI_IntersectRect
************************************************************************************************************/
#include "GUI_Protected.h"

/*************************************************************************************************************
             GUI__IntersectRects
Purpose:
  Calc intersection of rectangles
Add. info:
  Rectangles are passed as pointers. These pointers need to be valid;
  a NULL pointer may not be passed. There is no check for NULL pointers
  implemented in order to avoid avoid performance penalty.
  There is a similar function available, GUI__IntersectRects(),
  which takes 3 parameters and
  has a return value. Note that this one should be preferred because
  it is considerably faster and the call requires one parameter less.
*************************************************************************************************************/
void GUI__IntersectRect(GUI_RECT *pDest, const GUI_RECT *pr0) 
{
  if (pDest->x0 < pr0->x0)
    pDest->x0 = pr0->x0;
  if (pDest->y0 < pr0->y0)
    pDest->y0 = pr0->y0;
  if (pDest->x1 > pr0->x1)
    pDest->x1 = pr0->x1;
  if (pDest->y1 > pr0->y1)
    pDest->y1 = pr0->y1;
}