Box 40, 140, 320, 20, OFF
    DrawScreen

    Randomize 3

    Const noisew = 400
    Const noiseh = 300

    Dim noisepattern(noisew*3, noiseh) As Float
    Dim prenoise(noisew*3-1, noiseh-1) As Float
    Dim noise(noisew*3-1, noiseh-1, 1) As Float

    Function getinterpnoise#(i, j)
        ii# = Float(i/16.0)
        jj# = Float(j/16.0)
        aa# = noisepattern(RoundDown(ii#)+1, RoundDown(jj#))*(ii#-RoundDown(ii#))+noisepattern(RoundDown(ii#), RoundDown(jj#))*(1.0-(ii#-RoundDown(ii#)))
        bb# = noisepattern(RoundDown(ii#)+1, RoundDown(jj#)+1)*(ii#-RoundDown(ii#))+noisepattern(RoundDown(ii#), RoundDown(jj#)+1)*(1.0-(ii#-RoundDown(ii#)))
        Return bb#*(jj#-RoundDown(jj))+aa#*(1.0-(jj#-RoundDown(jj#)))
    EndFunction

    For i = 0 To noisew*3
        For j = 0 To noiseh
            noisepattern(i, j) = Rnd(-1.0, 1.0)
        Next j
        If i Mod 20 = 0 Then
            Box 40, 140, 320, 20, OFF
            Box 42, 142, 316*.333*i/Float(noisew)/3, 16
            DrawScreen
        EndIf
    Next i

    For i = 0 To noisew*3-1
        For j = 0 To noiseh-1
            prenoise(i, j) = getinterpnoise#(i, j)
        Next j
        If i Mod 20 = 0 Then
            Box 40, 140, 320, 20, OFF
            Box 42, 142, 316*.333*(1.0+i/Float(noisew)/3), 16
            DrawScreen
        EndIf
    Next i

    For i = 1 To noisew*3-2
        For j = 1 To noiseh-2
            noise(i, j, 0) = (prenoise(i,j+1)-prenoise(i,j-1))*2.0
            noise(i, j, 1) = (prenoise(i+1,j)-prenoise(i-1,j))*2.0
        Next j
        If i Mod 20 = 0 Then
            Box 40, 140, 320, 20, OFF
            Box 42, 142, 316*.333*(2.0+i/3/float(noisew)), 16
            DrawScreen
        EndIf
    Next i

    Dim parts(2999, 2) As Float
    For i = 0 To 2999
        parts(i,2)=-1.0
    Next i
    ptimer = Timer()

    spawn = 15'4

    Repeat
        fc+1
        spawn = spawn + UpKey() - DownKey()
        spawned = 0
        ra = 0
        ia#=Sin(fc*7.0/11*2)/2.0+0.5
        'If wrapangle(fc*7.0/11)<180 Then
            ib#=1-ia
            oc=noisew'255
            ocy=Cos(fc)*16
        'Else
        '    ib#=1-ia
        '    oc=512
        'EndIf
        Lock
            For i = 0 To 2999
                If parts(i,2)>0 Then
                    ra = ra + 1
                    parts(i,0) = parts(i,0)+noise(Int(parts(i, 0)), Int(parts(i, 1))-ocy, 0)*ia+noise(Int(parts(i, 0))+oc, Int(parts(i, 1))+ocy, 0)*ib
                    parts(i,1) = parts(i,1)-noise(Int(parts(i, 0)), Int(parts(i, 1))-ocy, 1)*ia-noise(Int(parts(i, 0))+oc, Int(parts(i, 1))+ocy, 1)*ib-.3-parts(i,2)/512.0
                    parts(i,2) = parts(i,2)-1.25
                    col = Max(0, Min(255, parts(i,2)))
                    'PutPixel2 parts(i,0),parts(i,1),col
                    'PutPixel2 parts(i,0)+1,parts(i,1),col
                    Color col, (col*.055)^2.0, 0
                    Line parts(i,0),parts(i,1),parts(i,0)+2,parts(i,1)
                    Line parts(i,0),parts(i,1)+1,parts(i,0)+2,parts(i,1)+1
                    'For x = parts(i,0)-2 to parts(i,0)+2
                    '    Line x, parts(i,1)-2, x, parts(i,1)+2
                    'Next x
                Else
                    If spawned<spawn Then
                        parts(i,0) = Rnd(80.0+100+Sin(fc)*40, 320.0-100+Sin(fc)*40)
                        parts(i,1) = Rnd(180.0, 200.0)
                        parts(i,2) = 255.0
                        spawned = spawned + 1
                    EndIf
                EndIf
            Next i
        Unlock
        Color 255, 255, 255
        Text 10, 220, "fp"+"s is "+Str(FPS())
        Text 10, 240, "rendering "+Str(ra)+" particles"
        Text 10, 260, "spawning "+Str(spawn+1)+" per frame"
        DrawScreen
    Forever