函数名: linerel

功 能: 从当前位置点(CP)到与CP有一给定相对距离的点画一直线

用 法: void far linerel(int dx, int dy);

程序例:

#include

#include

#include

#include

int main(void)

{

/* request auto detection */

int gdriver = DETECT, gmode, errorcode;

char msg[80];

/* initialize graphics and local variables */

initgraph(&gdriver, &gmode, "");

/* read result of initialization */

errorcode = graphresult();

if (errorcode != grOk)

{

printf("Graphics error: %s\",

grapherrormsg(errorcode));

printf("Press any key to halt:");

getch();

exit(1);

}

/* move the C.P. to location (20, 30) */

moveto(20, 30);

/* create and output a

message at (20, 30) */

sprintf(msg, " (%d, %d)", getx(), gety());

outtextxy(20, 30, msg);

/* draw a line to a point a relative

distance away from the current

value of C.P. */

linerel(100, 100);

/* create and output a message at C.P. */

sprintf(msg, " (%d, %d)", getx(), gety());

outtext(msg);

/* clean up */

getch();

closegraph();

return 0;

}