REM --- Screen - Amiga BASIC Graphics demo --- 20-July-85
DEFINT A-Z 
  
  IF FRE(-1)<60000 THEN
    PRINT "Sorry, this demo requires a
    PRINT "machine with 512k of memory
    END
  END IF
  SCREEN 1,320,200,5,1
  WINDOW 2,"Lines",(10,10)-(270,170),15,1
  PALETTE 1,0,0,1
  PALETTE 2,0,1,0
  DIM Pattern0%(3)
  DIM Pattern1%(3)
  DIM Pattern2%(3)
  FOR I=0 TO 3
    READ Pattern0%(I)
    READ Pattern1%(I)
    READ Pattern2%(I)
  NEXT I
  DATA &HAAAA, &H3333, &HFFFF
  DATA &H5555, &H3333, &HFFFF
  DATA &HAAAA, &H3333, &HFFFF
  DATA &H5555, &H3333, &HFFFF

  WHILE 1
    CLS
    GetWindowDim winWidth, winHeight
    FOR I=1 TO 8
      iPat=RND*3
      IF iPat=0 THEN
        PATTERN -1,Pattern0%
      ELSEIF iPat=1 THEN
        PATTERN -1,Pattern1%
      ELSEIF iPat=2 THEN
        PATTERN -1,Pattern2%
      END IF

      color1 = 2*I+2
      color2 = color1+1
      PALETTE color1,RND,RND,RND
      PALETTE color2,RND,RND,RND
      COLOR color1,color2

      x = winWidth/2
      y = winHeight/2
      cosI! = (9-I)*0.1*COS(I)
      sinI! = (9-I)*0.1*SIN(I)
      XcosI = x*cosI!
      XsinI = x*sinI!
      YcosI = y*cosI!
      YsinI = y*sinI!
      AREA (x+XcosI,y+YsinI)
      AREA (x+XsinI,y-YcosI)
      AREA (x-XcosI,y-YsinI)
      AREA (x-XsinI,y+YcosI)
      AREAFILL
    NEXT I
  WEND

SUB GetWindowDim(winWidth, winHeight) STATIC
  winWidth = WINDOW(2)
  winHeight = WINDOW(3)
  END SUB