Graphics 640,480,16,2
setbuffer backbuffer()

While Not KeyHit(1)
Cls
mx = MouseX() : my = MouseY()
x# = 320 : y# = 240 : zx = mx : zy = my
; Refraktor
; w = 30 : s = 1

; Eisblitz
; w = 20 : s = 10

; Blitz
 w = 4 : s = 30

; Blitz 2
; w = 15 : s = 30

; Blitz 3
; w = 10 : s = 70
blitz(x#,y#,mx,my,w,s)


Flip
Wend
End

Function blitz(x1,y1,x2,y2,weite = 10, staerke = 20)
If weite > 0 And staerke>0
winx = GraphicsWidth()-1 : winy = GraphicsHeight()-1
r = 255 : g = 255 : b = 255 ; <-- Farbe kann hier definiert werden

x# = x1 : y# = y1 : difx = x2-x1 : dify = y2-y1


f = r*$10000 + g*$100 + b
LockBuffer BackBuffer()

While e=0
ow# = w#
w# = ATan2(x2-x#,y2-y#)

For b=1 To weite
 w# = w# + Rnd(staerke*-1,staerke)
 x# = x# + Sin(w#) : y# = y# +Cos(w#)
If x#>=0 And x#<winx And y#>=0 And y#<winy Then WritePixelFast x#,y#,f
newdifx = x2-x# : newdify = y2-y#

If ((difx>=0 And newdifx<=0) Or (difx<=0 And newdifx>=0)) And ((dify>=0 And newdify<=0) Or (dify<=0 And newdify>=0)) Then e = 1 : Exit

Next
Wend

UnlockBuffer BackBuffer()
End If
End Function

setbuffer backbuffer()

...
winx = 640 : winy = 480     ; <-- Fenstergröße bitte angeben
...