for (x = lev.left; x < lev.right; x++)
for (y = lev.top; y < lev.bottom; y++)
lev.next[x][y] = lev.draw[x][y] = lev.cave[x][y];
lev.time = cav.time_seconds;
for (x = lev.left; x < lev.right; x++)
for (y = lev.top; y < lev.bottom; y++)
lev.next[x][y] = lev.draw[x][y] = lev.cave[x][y];
lev.time = cav.time_seconds;