;@modern
; A rock falls on a ship: a collision from the hardware and from PMOverlap

BYTE ARRAY ship=[$18 $3C $7E $FF $FF $DB $81 $81],
           rock=[$3C $7E $FF $FF $FF $FF $7E $3C]

PROC Main()
  BYTE y, hw=[0], sw=[0]

  PMGraphics(1)
  PMCreate(0, ship, 8, 1, 120, 180)   ; the ship at the bottom
  PMCreate(1, rock, 8, 1, 120, 100)   ; the rock above it
  PMColor(0, 1, 12)
  PMColor(1, 2, 6)
  PMWait()
  HitClr()

  FOR y=101 TO 190
  DO
    PMWait()                          ; the rock at y-1 is on the screen now
    IF hw=0 AND PMHitPM(1)&1 THEN     ; player 1 met player 0
      hw=y-1
    FI
    HitClr()
    PMVPos(1, y)                      ; the rock one row lower
    IF sw=0 AND PMOverlap(0, 1) THEN  ; the rectangles overlap at once
      sw=y
    FI
  OD

  Print("PMOverlap: the rock hit the ship at y=")
  PrintBE(sw)
  Print("Hardware:  the rock hit the ship at y=")
  PrintBE(hw)
RETURN