Bezier Intersections

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iroker

i have the solution here is it:

Function  FindRootsPoly3(A3#,A2#,A1#,A0#)

	Local fc2#,gc2#,hc2#,Rc2#,Sc2#,Tc2#,Uc2#,ic2#,jc2#,kc2#,Lc2#,Mc2#,Nc2#,Pc2#
	  
	fc2 =( (3*A1/A3) - ((A2^2)/(A3^2) ))/ 3
	gc2=(( (2*A2^3)/(A3^3)) - (9*A2*A1/(A3^2)) + (27*A0/A3)) / 27
	hc2 = ((gc2^2)/4) + ((fc2^3)/27)
	
	If hc2>0 Then
				Rc2 = -(gc2/2) + (Sqr(hc2))
				If Rc2<0 Then 
					Sc2 = -(Abs(Rc2)^0.333333)
				Else
					Sc2 = ((Rc2))^0.333333
				EndIf
				Tc2 = -(gc2/2) -( Sqr(hc2))
				If Tc2<0 Then 
					Uc2 = -(Abs(Tc2)^0.333333)
				Else
					Uc2 = (Tc2)^0.333333
				EndIf
				Rx(0) = (Sc2 + Uc2) - (A2/(3*A3))
				Else
				If hc2=0 And gc2=0 And fc2=0 Then
					Rx(0) =-((A0/A3)^0.3333333 )
				Else
					If hc2<0 Or hc2=0 Then
						ic2= Sqr(((gc2^2)/4) - hc2)
						jc2 = (ic2)^0.333333
						kc2 = ACos (- (gc2 / (2*ic2)))
						Lc2 = -jc2
						Mc2 = Cos (kc2/3)
						Nc2 = Sqr( 3) * Sin (kc2/3)
						Pc2 = -(A2/(3*A3))
						Rx(0) = 2*jc2 * Cos(kc2/3) -(A2/(3*A3))
						Rx(1) = Lc2 * (Mc2 + Nc2) + Pc2
						Rx(2) = Lc2 * (Mc2 - Nc2) + Pc2
				   EndIf		
			  EndIf
	EndIf
End Function

this calculates only the real roots
they are Rx(0), Rx(1), Rx(2)

i am using this code in my AiEditor for Racer
my Site

here a pic of this