LÖVE

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function PhysActor:CalculateOrbit()
--This function derives everything you need to know about a single orbiting body. 

			local bodyPos = Vector.new(self.body:getPosition())
			local bodyVel = Vector.new(self.body:getLinearVelocity())		

			local celPos = Vector.new(self.currentCelestialB.body:getPosition())		

			--get the velocity of the body
			local V = bodyVel:length()		

			--get the distance from the foci
			local R = bodyPos:distanceTo(celPos)		

			--Get the Zenith Angle
			local Anglefrombody  =  bodyPos:angleTo(celPos)
			local bodyFromAngle  =  celPos:angleTo(bodyPos)
			local Angle = math.deg( math.atan2(bodyVel.y,bodyVel.x))
			local Zenith =  Angle - Anglefrombody 
			local GM = (constant * self.currentCelestialB.body.fakeMass)
	

			-- tan V  = (r1 × v12 / GM) × sin  × cos  / [(r1 × v12 / GM) × sin2  - 1
			--tanV = (6628140*math.pow(7900,2)/3.986005e14) * math.sin(math.rad(89)) * math.cos(math.rad(89)) / ((6628140*math.pow(7900,2)/3.986005e14) * math.pow(math.sin(math.rad(89)),2) - 1)
			-- this formula is to locate where the body is from the perrigee
			local tanVx = (R*math.pow(V,2)/GM) * math.sin(math.rad(Zenith)) * math.cos(math.rad(Zenith)) 
			local tanVy =  ((R*math.pow(V,2)/GM) * math.pow(math.sin(math.rad(Zenith)),2) - 1)
			local tanV = math.atan2(tanVx,tanVy)

			local tanVDeg = math.deg(tanV)
			local PerigeeFromZeroAngle =  bodyFromAngle - ( tanVDeg - 180) --WOOO!
			local PerigeeFromZeroAngle =  bodyFromAngle -  tanVDeg  --WOOO

			local C = (2 * GM) / (R* math.pow(V,2))

			local Rh = (-C + math.sqrt( math.pow(C,2) - 4 * (1-C) * -math.pow(math.sin(math.rad(Zenith)),2) )) / (2*(1-C))
			local Rl = (-C - math.sqrt( math.pow(C,2) - 4 * (1-C) * -math.pow(math.sin(math.rad(Zenith)),2) )) / (2*(1-C))		
		
			local Rlower = math.min(Rh,Rl)
			local Rhigher = math.max(Rh,Rl)		

			local PerigeeRadius = R * Rlower 
			local ApogeeRadius = R * Rhigher		

			--Eccentricity
			--e = SQRT[ (r1 × v12 / GM - 1)2 × sin2  + cos2  ]
			local E = math.sqrt( math.pow((R * math.pow(V,2)/ GM -1),2) * math.pow(math.sin(math.rad(Zenith)),2) + math.pow(math.cos(math.rad(Zenith)),2))		


			--SEMI MAJOR AXIS
			--a = 1 / ( 2 / r1 - v12 / GM )		

			local SemiMajorAxis = 1/(2 / R - math.pow(V,2) / GM)

			--theta = E * math.sin(math.rad(225)) /  (1 + E * math.cos(math.rad(225)))
			--theta = 0.1 * math.sin(math.rad(225)) /  (1 + 0.1 * math.cos(math.rad(225)))
			--theta = math.atan(theta)		

  
			 self.predictedPoints = {}
			 self.predictedPoints2 = {}		
			 self.perigee = {}
			 self.currentAng = {}

			-- print("Vel:"..V)
			-- print("initDist"..R)
			--print("perigeeFromZero:"..PerigeeFromZeroAngle,tanVDeg)
			-- print("eccentricity:"..E)
			-- print("PerigeeRadius:"..PerigeeRadius)
			-- print("ApogeeRadius:"..ApogeeRadius)
			-- print("SemiMajorAxis:"..SemiMajorAxis)
			-- print("C:"..C)
			-- print("Zenith:"..Zenith)
			-- print("Velocity:"..V)

			self.perigee[1] = 0
			self.perigee[2] = 0	
			self.perigee[3] = math.cos(math.rad(PerigeeFromZeroAngle))*(PerigeeRadius)
			self.perigee[4] = math.sin(math.rad(PerigeeFromZeroAngle))*(PerigeeRadius)

			self.currentAng[1] = 0
			self.currentAng[2] = 0	
			self.currentAng[3] = math.cos(math.rad(PerigeeFromZeroAngle+tanVDeg))*(PerigeeRadius)
			self.currentAng[4] = math.sin(math.rad(PerigeeFromZeroAngle+tanVDeg))*(PerigeeRadius)


			for i=1,361 do
				Vang = i 

				--V is angle from perrigee		

				PointDist = SemiMajorAxis * (1- math.pow(E,2)) / (1+ E * math.cos(math.rad(Vang)))		
		
				PointAngle =   Vang +  PerigeeFromZeroAngle
				--PointAngle =   Vang

				Point = Vector.new(PointDist*math.cos(math.rad(PointAngle)),PointDist*math.sin(math.rad(PointAngle)))		

				table.insert(self.predictedPoints,Vang+800)
				table.insert(self.predictedPoints,PointDist/10)
				table.insert(self.predictedPoints2,Point.x)
				table.insert(self.predictedPoints2,Point.y)	

			end		
		
end