I’ve never really been able to wrap my head around inverse kinematics, well I can, just using it with the proper Motor joints on the character just causes me issues. I’ve been toying with the script below but there’s just one problem. The hand and overall arm never actually points to the center of the actual part, always seems to be extremely far away. Now it’s understandable for animations to cause a bit of deviation but I can’t seem to come up with a fix of any sort.
Now, this script is basically the normal resource used for this topic, but of course has the same exact issue.
Script
LocalScript that goes inside of “StarterCharacterScripts” mostly lazy, with a part named “Front” in workspace.
local Pi = math.pi;
local halfPi = Pi/2;
local ForwardV3 = Vector3.new(0,0,-1);
local function solvearm(originCFrame,target,a,b)
local localized = originCFrame:pointToObjectSpace(target);
local localizedUnit = localized.unit;
local axis = ForwardV3:Cross(localizedUnit);
local angle = math.acos(-localizedUnit.Z);
local plane = originCFrame*CFrame.fromAxisAngle(axis,angle);
local c = localized.Magnitude;
if c < math.max(a,b)-math.min(a,b) then
return plane * CFrame.new(0,0,math.max(b,a)-math.min(b,a)-c), halfPi, Pi;
elseif c > a+b then
return plane, halfPi, 0;
else
local theta1 = -math.acos((-(b*b) + (a*a) + (c*c)) / (2*a*c));
local theta2 = math.acos(((b*b) - (a*a) + (c*c)) / (2*b*c));
return plane, theta1 + halfPi, theta2 - theta1;
end;
end;
local UpperTorso = script.Parent.UpperTorso;
local RightUpperArm = script.Parent.RightUpperArm;
local RightLowerArm = script.Parent.RightLowerArm;
local RightShoulder = RightUpperArm.RightShoulder;
local RightElbow = RightLowerArm.RightElbow;
local RightShoulderInt = RightShoulder.C0;
local RightElbowInt = RightElbow.C0;
local targetPos = workspace:WaitForChild("Front");
local Tp0 = CFrame.new((UpperTorso.CFrame * CFrame.new(1.25,0,-1)).p) * CFrame.Angles(0,math.pi/2,0);
while game:GetService("RunService").RenderStepped:Wait() do
--targetPos.Position =
local PosSize = (targetPos.Size / 2).Magnitude
local TargetPos = targetPos.Position;
local ShoulderCF = UpperTorso.CFrame * RightShoulderInt;
local Plane, ShoulderAngle, ElbowAngle = solvearm(ShoulderCF, TargetPos, RightLowerArm.Size.Y, RightUpperArm.Size.Y);
if Plane then
RightShoulder.C0 = UpperTorso.CFrame:toObjectSpace(Plane) * CFrame.Angles(ShoulderAngle,0,0);
RightElbow.C0 = RightElbowInt * CFrame.Angles(ElbowAngle,0,0);
end
end;
If anyone is able to help point out what I’m doing wrong or recommend anything it’d be fantastic! I’ve honestly spent years trying to get proper IK but it just doesn’t work with my brain.
