求 读去bmp文件的tc源程序，谢谢

[DreamingPig]

email：[e-mail]

[daizh]

/*--------------------256bmp.c----------------------*/
#include "dos.h"
#include "stdio.h"
#include "process.h"
#include "bios.h"

void selectpage(register char page) /*换页函数*/
{ union REGS r;
r.x.ax=0x4f05;
r.x.bx=0;
r.x.dx=page; /*选择页面*/
int86(0x10,&r,&r);
}
unsigned char set_SVGA_mode(int vmode) /*设置SVGA屏幕模式*/
{ union REGS r;
r.x.ax=0x4f02;
r.x.bx=vmode;
int86(0x10,&r,&r);
return(r.h.ah);
}
unsigned int get_SVGA_mode() /*获取当前SVGA屏幕模式*/
{ union REGS r;
r.x.ax=0x4f03;
int86(0x10,&r,&r);
return(r.x.bx);
}
void main()
{ char buffer[640],page_new=0,page_old=0;
int i,j,k,n,r,g,b,savemode;
long position,width,length;
FILE *fp;
puts("This is a 256 color bmp viewer! Author:WuJin");
puts("Input filename:"); /*输入要显示的BMP文件路径*/
gets(buffer);
if((fp=fopen(buffer,"rb"))==NULL)
{ printf("Can't open file: %s",buffer);
return;
}
fseek(fp,28,SEEK_SET);
fread(&i,2,1,fp);
if(i!=8) /*检查是否为256色位图*/
{ puts("Not a 256 color bitmap!");
fclose(fp);exit(0);
}
fseek(fp,18,SEEK_SET);
fread(&width,4,1,fp);
fread(&length,4,1,fp);
savemode=get_SVGA_mode(); /*先保存原来的屏幕模式*/
set_SVGA_mode(0x101); /*硬件无关性初始化屏幕为640*480 256色模式*/
fseek(fp,54,SEEK_SET);
for(i=0;i<256;i++) /*按照该图片的DAC色表设置色彩寄存器*/
{ b=fgetc(fp);g=fgetc(fp);r=fgetc(fp); /*获取R、G、B分量*/
outportb(968u,i);
outportb(969u,r>>2);
outportb(969u,g>>2);
outportb(969u,b>>2);
fgetc(fp);
}
k=(width%4)?(4-width%4):0; /*宽度修正值*/
for(j=length-1;j>=0;j--)
{ fread(buffer,width,1,fp);
for(i=0,n=0;i<width;i++,n++)
{ position=j*640l+i; /*计算要显示点的显存位置*/
page_new=position/65536l; /*计算显示页*/
if(page_new!=page_old) /*当显示页不同时更换页面，提高一定的输出速度*/
{selectpage(page_new);page_old=page_new;}
pokeb(0xa000,position%65536l,buffer[n]); /*写到显存位置*/
}
fseek(fp,k,SEEK_CUR); /*每行绘制完后修正宽度*/
}
fclose(fp);
bioskey(0);
set_SVGA_mode(savemode); /*恢复屏幕*/
}

[0738111080]

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