pset422a.c

来自「linux嵌入式开发程序」· C语言 代码 · 共 36 行

/*===========================================================================
        2D Graphics Library
        ALL RIGHTS RESERVED, COPYRIGHT (C) FUJITSU LIMITED 1993-2002
        LICENSED MATERIAL - PROGRAM PROPERTY OF FUJITSU LIMITED
 ===========================================================================*/

#include "gl.h"
#include "defhook.h"

int
_GL_psetYUV422_average(GL_WP *gp)
{
    register DWORD *adr ;
    register DWORD d = gp->pnt.offs ;
    register DWORD o ;

    adr  = _AddAdr(gp->hwork.VRAMadr[gp->hwork.page][0],gp->pnt.offs) ;

    if(((long)adr&3)!=0){
        adr = (DWORD *)((long)adr-((long)adr&3)) ;
        o = *adr ;
        *adr   = ( d & 0x0000ff00 )
               | ( o & 0xff000000 )
               | ( ( ( (d&0x00ff00ff)+(o&0x00ff00ff) )>>1)& 0x00ff00ff ) ;

    } else {
        o = *adr ;
        *adr   = ( d & 0xff000000 )
               | ( o & 0x0000ff00 )
               | ( ( ( (d&0x00ff00ff)+(o&0x00ff00ff) )>>1)& 0x00ff00ff ) ;
    }
    return GL_Ok ;
}