函数名: getviewsetting

功 能: 返回有关当前视区的信息

用 法: void far getviewsettings(struct viewporttype far *viewport);

程序例:

#include <graphics.h>

#include <stdlib.h>

#include <stdio.h>

#include <conio.h>

char *clip[] = { "OFF", "ON" };

int main(void)

{

/* request auto detection */

int gdriver = DETECT, gmode, errorcode;

struct viewporttype viewinfo;

int midx, midy, ht;

char topstr[80], botstr[80], clipstr[80];

/* initialize graphics and local variables */

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

/* read result of initialization */

errorcode = graphresult();

if (errorcode != grOk) /* an error occurred */

{

printf("Graphics error: %s\", grapherrormsg(errorcode));

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

getch();

exit(1); /* terminate with an error code */

}

midx = getmaxx() / 2;

midy = getmaxy() / 2;

/* get information about current viewport */

getviewsettings(&viewinfo);

/* convert text information into strings */

sprintf(topstr, "(%d, %d) is the upper left viewport corner.",

viewinfo.left, viewinfo.top);

sprintf(botstr, "(%d, %d) is the lower right viewport corner.",

viewinfo.right, viewinfo.bottom);

sprintf(clipstr, "Clipping is turned %s.", clip[viewinfo.clip]);

/* display the information */

settextjustify(CENTER_TEXT, CENTER_TEXT);

ht = textheight("W");

outtextxy(midx, midy, topstr);

outtextxy(midx, midy+2*ht, botstr);

outtextxy(midx, midy+4*ht, clipstr);

/* clean up */

getch();

closegraph();

return 0;

}