How would you detect which side of the door (or part) the player is on?

Help and Feedback Scripting Support
#1

Hello! I’m making an interaction system that includes doors, as shown below.

The problem is that I don’t know how to calculate which side the player is on to ensure I open the door in the opposite direction so that the door doesn’t always hit the player opening the door.

I was told I could use :Dot(), but until now I’ve never heard of it and when I looked it up it seemed very confusing.

I have however managed to do a VERY hacky approach to temporarily solve my problem, but I’d like to improve it and ensure that it’s a stable approach rather than what I have now.

Video of current code:
https://streamable.com/xhilre (In link form because it wouldn’t upload)

Current code that calculates which side the player is on:

local relativeCFrame = character:WaitForChild("HumanoidRootPart").CFrame * StaticDoorPart.CFrame.lookVector

if relativeCFrame.Z > -47 then
	tweenModel(door, door.Parent:WaitForChild("BackOpenPosition").CFrame)
else
	tweenModel(door, door.Parent:WaitForChild("FrontOpenPosition").CFrame)
end

I know this might be a very ineffective solution I’ve got but it’s all I could figure out.

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Door Mechanics (Open System)
#2

You can use two different parts, so when one get touched you can rotate the part in the right way

#3

I could, but I would rather not to simplify things for the builders of the game.

#4

I’ll say you can use RayCasting, but using it you must be sure the player is in front of the door. Else you can use a Region3, but this could make the things a bit more complicated

#5

Use this simple code to detect which part is near then insert your code for the position you want the door open at.

local player = game.Players.LocalPlayer
local character = player.Character
local door = workspace.Door
local back = workspace.Back
local front = workspace.Front
while wait() do
local back = (back.Position - script.Parent.Torso.Position).Magnitude
local front = (front.Position - script.Parent.Torso.Position).Magnitude
if back > front then
	print("Front " .. math.floor(front))
	else
	print("Back " .. math.floor(back))
end
end

Edit that code on your style.

#6

:Dot() is just a simple means of saying “How similarly do two Vector3’s face?”
If they are facing largely in the same direction, :Dot() returns a positive number.
If they are perpendicular, :Dot() returns 0.
If they are facing in opposite directions, :Dot() returns a negative number.

Consider the following segment:

local doorToChar = character.HumanoidRootPart.Position - StaticDoorPart.Position 
--Get a vector that goes from the door to the character
local doorLookVect = StaticDoorPart.CFrame.lookVector
--Get the vector where the door itself faces
if doorToChar:Dot(doorLookVect) > 0 then
--Character is in front of the door
else
--Character is behind the door
end
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