I am trying to make a curve function that returns a set of positions. I only have 2 points, how do i make a smooth curve out of these 2 point?
I’ve looked at Bezier Curves but it takes at least 3 points to get a curve.
How is the function supposed to know what kind of curve you want?
There are an infinite amount of options, every smooth curve from points function takes atleast 3 points to know what you want.
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pretty sure you would always need a third point to tell how intense the curve is going to be if its 2 points then its just a line m8.
By giving the three points to a bezier curve function?
If you mean “how do I calculate the third point” then it depends on where you want the third point to be:
What direction do you want the L curve? How smooth should it be? etc…
I learned a lot from this module to create tween bezier curves with 3 points dinamycally, to make a part travel all the points
Bezier Curve Creator
You can generate a right angle triangle between the points, but then still you don’t know which side…
test the 3, I made the arguments easier to read
Lerp
local function Lerp(Start, End, Time)
return Start + (End - Start) * Time
end
local Start = Vector2.new(0, 0) -- top left
local End = Vector2.new(1, 1) -- bottom right
for Time=0, 1, 0.01 do
print(Lerp(Start, End, Time))
end
Quadratic
local function QuadraticBezier(Time, Start, Middle, End)
return (1 - Time)^2 * Start + 2 * (1 - Time) * Time * Middle + Time^2 * End
end
local Start = Vector2.new(0, 0) -- top left
local Middle = Vector2.new(1, 0) -- top right I think
local End = Vector2.new(1, 1) -- bottom right
for Time=0, 1, 0.01 do
print(QuadraticBezier(Time, Start, Middle, End))
end
Cubic
local function CubicBezier(Time, Start, Middle1, Middle2, End)
return (1 - Time)^3*Start + 3*(1 - Time)^2*Time*Middle1 + 3*(1 - Time)*Time^2*Middle2 + Time^3*End
end
local Start = Vector2.new(0, 0) -- top left
local Middle1 = Vector2.new(1, 0) -- top right
local Middle2 = Vector2.new(0, 1) -- bottom left
local End = Vector2.new(1, 1) -- bottom right
for Time=0, 1, 0.01 do
print(CubicBezier(Time, Start, Middle1, Middle2, End))
endYou must have at least 1 extra point.
What you linked needs more than 2 points.
What you posted also needs more than 2 points (except for the lerp but that isn’t a curve).
Also Artzified’s link
has the code you posted
This has already been said.
Please read the post and it’s replies to see whether your otherwise useful replies are needed.
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Here’s some pseudo code to generate the third point
- Get the center point between the 2 points (green)
- Get the distance between the 2 points (diameter of the black circle)
- Get the angle from the center point of one of the 2 points (yellow angle)
(the orangle line is 0°) - Add 90° to the angle (pink angle)
- Generate the position of the third point using the new angle (red point)
Depending on which point you calculate the angle from and whether you add or subtract 90° you can choose which of the 2 red points you want.
Thats what I said… 3 points… I support that having 3 points its needed…
3 points and even more its helpful
The link you posted is helpful, but it isn’t what Artzified asked for, he already has code to generate a bezier curve
He just needs an alternative to bezier curves that doesn’t need 3 points (doesn’t exist), or a way to generate the third point.
yeah… if using less than 3 points its not possible, and not knowing how to generate the point 3, I just provided a module to check to understand the using the 3 points, documentation never harms… ¬¬
i’m having trouble getting the angle. is this correct?
local angle = (p1 - centerPoint).Unit:Dot(p2)
which one?
I meant something more like this
local p1Offset = p1 - centerPoint
local angle = math.atan2(p1Offset.Y, p1Offset.X)
+ math.rad(90) -- add the 90° right away, no need to wait
Then generate the new point like so
local radius = diameter / 2
local thirdPoint = Vector2.new( math.cos(angle) * radius, math.sin(angle) * radius )
It doesn’t seem to work when i visualize it in 3d space
local diameter = (p1.Position-p2.Position).Magnitude
local centerPoint = (p1.Position-p2.Position) / 2
local offset = p1.Position - centerPoint
local angle = math.atan2(offset.Y, offset.X) + math.rad(90)
local radius = diameter/2
local thirdPoint = Vector3.new(math.cos(angle) * radius, math.sin(angle) * radius)
No in 3d it wouldn’t work, because then you have an infinite amount of red points (the red circle)
What do the 2 points represent and why do you need an L shaped angle between them?
