C语言程序设计实训 release目录

				/*7-1.c*/
				#include "graphics.h"
				#include "dos.h"
				#include "stdio.h"
				#define ENABLE 0x0F
				#define INDEXREG 0x3CE
				/*定义索引寄存器端口地址*/
				#define VALREG 0x3CF
				/*定义数据寄存器端口地址*/
				#define VGABASE 0xA0000000L
				#define WIDTH 80L
				#define XMAX 639
				#define YMAX 479
				#define XMIX 0
				#define YMIN 0
				#define OUTINDEX(index,val)  outport(INDEXREG,index);outport(VALREG,val);
				char far *vgabase;
				void putpoint(int x,int y,int color,int how);
				main()
				{
				int gmode=VGAHI,gdriver=VGA;
				int color=1,x,y;
				initgraph(&gdriver,&gmode,"");
				/*绘制各种颜色的直线段*/
				for(y=1;y				for(x=1;x				putpoint(x,y,color,0);
				color++;}
				getch();
				/*用异或方式擦除各条直线*/
				color=1;
				for(y=1;y				for(x=1;x				putpoint(x,y,color,0x18);
				color++;}
				getch();
				closegraph();
				     }
				
				/*利用图形控制寄存器功能写像素函数*/
				void putpoint(int x,int y,int color,int how)
				{
				register unsigned char mask=0x80;
				register char far *base;
				unsigned dummy;
				vgabase=(char far *)MK_FP(0xA000,0);
				base=(char far *)(vgabase+((long)y*
				WIDTH+(long)x/8L));
				mask>>=x%8;
				dummy=*base;
				OUTINDEX(0,color);/*设定额色*/
				OUTINDEX(1,ENABLE);/*启动位平面*/
				OUTINDEX(3,how); /*确定逻辑操作方式*/
				OUTINDEX(8,mask);/*设置屏蔽位*/
				*base=1;
				OUTINDEX(0,0);/*寄存器复位*/
				OUTINDEX(1,0);
				OUTINDEX(3,0);
				OUTINDEX(8,0xff);
				}