' based on a QBJS program by Vince
' http://basic4all.epizy.com/index.php?topic=206.msg2187#new

Dim  as double sw, sh, r, rr0, sx, sy, mw, mx, my, mb, rr, valid, old_mx, old_my, old_mw

sw = 1280
sh = 768

Dim pi As Double
pi = 4 * Atn(1)

Dim As Double t, a, b, a1, a2
Dim As Double x, y, x0, y0, x1, y1, dx, dy

r = 210
rr0 = 140

sx = 0
sy = sh / 2
Screen _NewImage(sw, sh, 14)
_sndwave "square"

waitfornomousebutton:
getmouse nmx, nmy, nmw2, nmb
if nmb = 1 THEN goto waitfornomousebutton

Do

    'Do While _MouseInput
        'mw = mw + _MouseWheel
    'Loop
	 


    'If _KeyDown(87) or _KeyDown(119) then 'W
    '    mw = mw - 1
    'ElseIf _KeyDown(83) or _KeyDown(115) then 'S
    '    mw = mw + 1
    'End If
	 
	 this_inkey$ = ucase$(inkey$)
    If this_inkey$ = "W" then 'W
        mw = mw - 1
    ElseIf this_inkey$ = "S" then 'S
        mw = mw + 1
    End If

    ' mx = _MouseX
    ' my = _MouseY
    ' mb = _MouseButton(1)
	 getmouse mx, my, mw2, mb

    rr = rr0 - mw

    If mb Then
        Do While mb
            'Do While _MouseInput
            'Loop
            'mb = _MouseButton(1)
	         getmouse mx, my, mw, mb
        Loop

        valid = -1
        For b = 0 To 2 * pi Step 2 * pi / 3
            x1 = r * Cos(b) + sw / 2
            y1 = r * Sin(b) + sh / 2

            dx = mx - x1
            dy = my - y1
            If dx * dx + dy * dy < rr * rr Then
                valid = 0
                goto exitforB
            End If
        Next
		  exitforB:

        If valid Then
            sx = mx
            sy = my
        End If
    End If

    'if mx<>old_mx or my<>old_my or mw<>old_mw then
    'fading light
    If 1 Then



        'line (0,0)-(sw,sh), _rgb(0,0,0), bf
        'Line (0, 0)-(sw, sh), _RGBA32(0, 0, 0, 30), BF
		  Line (0, 0)-(sw, sh), &h000000, BF

        'locate 1,1
        '? mx, my, mw, mb
       
        For b = 0 To 2 * pi Step 2 * pi / 3
            Circle (r * Cos(b) + sw / 2, r * Sin(b) + sh / 2), rr, &hffffff
				Circle (r * Cos(b) + sw / 2, r * Sin(b) + sh / 2), rr-1, &hffffff
        Next
       
        a = _Atan2(my - sy, mx - sx)
       
        x0 = sx
        y0 = sy
       
        For t = 0 To 1000
            x = t * Cos(a) + x0
            y = t * Sin(a) + y0
           
            For b = 0 To 2 * pi Step 2 * pi / 3
                If x >= 0 And x < sw And y >= 0 And y < sh Then
                    x1 = r * Cos(b) + sw / 2
                    y1 = r * Sin(b) + sh / 2
                   
                    dx = x - x1
                    dy = y - y1
                    If dx * dx + dy * dy < rr * rr Then
                        a1 = _Atan2(dy, dx)
                        a2 = 2 * a1 - a - pi
                       
                        'Line (x0, y0)-(x, y), _RGB(233, 205, 89)
								Line (x0, y0)-(x, y), &hdfcd59
								sound 13, 0.00125
                        x0 = x
                        y0 = y
                        a = a2
                        t = 0
                        goto exitforA
                    End If
                End If
            Next
        exitforA:       
        Next

        'Line (x0, y0)-(x, y), _RGB(233, 205, 89)
		  Line (x0, y0)-(x, y), &hdfcd59
       
    End If

    old_mx = mx
    old_my = my
    old_mw = mw

    '_Display
    '_Limit 50
	 _delay 1/50
Loop Until _KeyHit = 27