' Trapped squareDEFINT A-ZSCREEN _NEWIMAGE(640, 480, 256)DIM w, h, x1, y1, x2, y2, dx, dy AS INTEGERw = _WIDTH(0): h = _HEIGHT(0)x1 = w / 2 - 50: y1 = h / 2 - 50x2 = x1 + 100: y2 = y1 + 100: dx = 1: dy = 1RANDOMIZE TIMERDO _LIMIT 100 LINE (x1, y1)-(x2, y2), _RGB(&H00, &H00, &H00), BF IF x1 < 1 THEN dx = RndRange(1, 3) IF y1 < 1 THEN dy = RndRange(1, 3) IF x2 >= w - 1 THEN dx = -RndRange(1, 3) IF y2 >= h - 1 THEN dy = -RndRange(1, 3) x1 = x1 + dx: y1 = y1 + dy: x2 = x2 + dx: y2 = y2 + dy LINE (x1, y1)-(x2, y2), _RGB(&HFF, &H40, &H40), BF _DISPLAYLOOP WHILE INKEY$ = ""ENDFUNCTION RndRange% (lo AS INTEGER, hi AS INTEGER)RndRange = INT(RND * (hi - lo + 1) + lo)END FUNCTION