reg15.c

nucleus 文件系统,内核和彩色图形系统,在小系统上非常好用

/*************************************************************************/
/*                                                                       */
/*         Copyright (c) 1997 - 1999 Accelerated Technology, Inc.        */
/*                                                                       */
/* PROPRIETARY RIGHTS of Accelerated Technology are involved in the      */
/* subject matter of this material.  All manufacturing, reproduction,    */
/* use, and sales rights pertaining to this subject matter are governed  */
/* by the license agreement.  The recipient of this software implicitly  */
/* accepts the terms of the license.                                     */
/*                                                                       */
/*************************************************************************/

/*************************************************************************/
/*                                                                       */
/* FILE NAME                                            VERSION          */
/*                                                                       */
/*      REG15.c                                          1.9             */
/*                                                                       */
/* COMPONENT                                                             */
/*                                                                       */
/*      All                                                              */
/*                                                                       */
/* DESCRIPTION                                                           */
/*                                                                       */
/*      This file contains the NullRegion and EmptyRegion functions.     */
/*                                                                       */
/* AUTHOR                                                                */
/*                                                                       */
/*      Giac Dinh, Accelerated Technology, Inc.                          */
/*                                                                       */
/* DATA STRUCTURES                                                       */
/*                                                                       */
/*      None                                                             */
/*                                                                       */
/* FUNCTIONS                                                             */
/*                                                                       */
/*      None                                                             */
/*                                                                       */
/* DEPENDENCIES                                                          */
/*                                                                       */
/*      None                                                             */
/*                                                                       */
/* HISTORY                                                               */
/*                                                                       */
/*         NAME            DATE                    REMARKS               */
/*                                                                       */
/*                                                                       */
/*************************************************************************/

#include "meta_wnd.h"
#include "metconst.h"    /* MetaWINDOW Constant & Stucture Definitions */
#include "metports.h"    /* MetaWINDOW Port & Bitmap Definitions */
#include "grafdata.h"
#include "metmacs3.h"


/* Function NullRegion modifies an existing region structure such that it contains no
rectangle list. The original allocated size of the region is not changed.  */
void NullRegion( region *argRegion )
{
	argRegion->rgnSize = sizeof(region) + 2 * sizeof(rect);

/* Flag as null  */
	argRegion->rgnFlags = 0;

/* Set bound to 0  */
	argRegion->rgnRect.Xmin = 0;
	argRegion->rgnRect.Xmax = 0;
	argRegion->rgnRect.Ymin = 0;
	argRegion->rgnRect.Ymax = 0;

/* Set end pointer first rect in list  */

	argRegion->rgnListEnd->Xmin = rgnEOS;
	argRegion->rgnListEnd->Xmax = rgnEOS;
	argRegion->rgnListEnd->Ymin = rgnEOS;
	argRegion->rgnListEnd->Ymax = rgnEOS;

/* Se start pointer to last rect in list  */

	argRegion->rgnList->Xmin = rgnBOS;
	argRegion->rgnList->Xmax = rgnBOS;
	argRegion->rgnList->Ymin = rgnBOS;
	argRegion->rgnList->Ymax = rgnBOS;
	
	return;
}


/* Function EmptyRegion checks an existing region structure 
   to see if it is a null region.  */
int EmptyRegion ( region * argRegion) 
{
	int value;

	if(!(argRegion->rgnFlags & rfNull)) return(0);

	value = argRegion->rgnRect.Xmin | argRegion->rgnRect.Xmax |
		argRegion->rgnRect.Ymin | argRegion->rgnRect.Ymax;

	if(value == 0) return(1);

	return(0);
}