Turbo C 2.0、Borland C++库函数及用例

Turbo C 2.0、Borland C++库函数及用例(44) modename);/* clean up */
getch();
closegraph();
return 0;
}
函数名: getimage
功 能: 将指定区域的一个位图存到主存中
用 法: void far getimage( int left, int top, int right,
int bottom, void far *bitmap);
程序例:#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
#include <alloc.h>void save_screen(void far *buf[4]);
void restore_screen(void far *buf[4]);int maxx, maxy;int main(void)
{
int gdriver=DETECT, gmode, errorcode;
void far *ptr[4]; /* auto-detect the graphics driver and mode */
initgraph(&gdriver, &gmode, "");
errorcode = graphresult(); /* check for any errors */ if (errorcode != grOk)
{
printf("Graphics error: %s\n",
grapherrormsg(errorcode)); printf("Press any key to halt:");
getch();
exit(1);
}
maxx = getmaxx();
maxy = getmaxy(); /* draw an image on the screen */
rectangle(0, 0, maxx, maxy);
line(0, 0, maxx, maxy);
line(0, maxy, maxx, 0); save_screen(ptr); /* save the current screen */
getch(); /* pause screen */ cleardevice(); /* clear screen */
restore_screen(ptr); /* restore the screen */
getch(); /* pause screen */ closegraph();
return 0;
}void save_screen(void far *buf[4])
{
unsigned size;
int ystart=0, yend, yincr, block; yincr = (maxy+1) / 4; yend = yincr;
size = imagesize(0, ystart, maxx, yend);
/* get byte size of image */
for (block=0; block<=3; block++)
{
if ((buf[block] = farmalloc(size)) == NULL)
{
closegraph();
printf("Error: not enough heap space in save_screen()\
.\n");
exit(1);
} getimage(0, ystart, maxx, yend, buf[block]);
ystart = yend + 1;
yend += yincr + 1;
}
}void restore_screen(void far *buf[4])
{
int ystart=0, yend, yincr, block; yincr = (maxy+1) / 4;
yend = yincr; for (block=0; block<=3; block++)
{
putimage(0, ystart, buf[block], COPY_PUT);
farfree(buf[block]);
ystart = yend + 1;
yend += yincr + 1;
}
}