Basically I am trying to Render a Curve inside a viewportframe and currently its very ineffective, Slow and laggy. Basically Im trying to render an orbit Inside the ViewPortFrame and as well known there trajectory is curved Currently Im trying to approximate this curve by using heaps of parts
However I cannot define a inertial reference frame directly in roblox so if I try to render say an orbit around a moon an object already moving I have no choice but to constantly Reposition all the orbit parts 60 times a second for a smooth render and the larger the orbit the more parts I need to approximate the curve nicely obviously this method sucks and unfortunetly beams don’t work inside of ViewPortFrames so I cannot approximate the curve using cubic beziers. This is incredibly limiting because it eats up a huge amount of frame time and visually it also looks bad and this also limits the amount of spacecraft and moons, etc I can have in the system. here is the code
local function drawEllipticalOrbit(BaryPosition, semiMajorAxis, eccentricity, inclination, longitudeOfAscendingNode, argumentOfPerihelion)
local numPoints = 100
local orbitPoints = {}
-- Calculate the transformation matrix
local m11, m12, m13, m21, m22, m23, m31, m32, m33 =
CalculatePerifocalToECIMatrix(inclination, longitudeOfAscendingNode, argumentOfPerihelion)
for j = 1, numPoints do
local angle = 2 * math.pi * j / numPoints
local eccentricity = calculateEccentricity(e_vector)
local semiMajorAxis = calculateSemiMajorAxis(r_mag, v_mag, mu)
local distance = semiMajorAxis * (1 - eccentricity^2) / (1 + eccentricity * math.cos(angle))
local x = distance * math.cos(angle)
local y = distance * math.sin(angle)
local z = 0
local x3 = m11 * x + m12 * y + m13 * z
local y3 = m21 * x + m22 * y + m23 * z
local z3 = m31 * x + m32 * y + m33 * z
local finalX, finalY, finalZ = PeriFocalToRoblox(-x3, y3, z3)
local finalPosition = Vector3.new(finalX, finalY, finalZ) + InertialFrame
table.insert(orbitPoints, finalPosition)
end
-- Create parts for each segment to connect points
for i = 1, #orbitPoints do
local pointA = orbitPoints[i]
local pointB = orbitPoints[i % #orbitPoints + 1]
local midPoint = (pointA + pointB) / 2
local distance = (pointA - pointB).Magnitude
local segment = Instance.new("Part")
segment.Size = Vector3.new(10, 10, distance)
segment.CFrame = CFrame.new(midPoint, pointB)
segment.Transparency = 0.5
segment.Color = Color3.fromRGB(92, 144, 255)
segment.Anchored = true
segment.Material = Enum.Material.Neon
segment.Parent = ViewportFrame.Render
segment.CanCollide = false
end
end
-- Draw the orbit relative to the planet's position
drawEllipticalOrbit(BaryPosition, semiMajorAxisStuds, eccentricity, inclination, longitudeOfAscendingNode, argumentOfPerihelion)
Basically it calculates the shape of the orbit from certain parameters I’ve calculated further up in the script from there we can calculate points along the orbit and join them together. Im wondering if anyone has any better ideas to draw a curve that isn’t so performance intensive.
This here is what happens if I crank up the part count too much roblox does some kinda script culling and it no longer refreshed at 60 times a second and you get this ugly mess
