For some reason its not detecting when a player comes into contact with another player

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#1

Title is pretty obvious, I made a kind of hitbox and whenever a model with a Humanoid goes into my hitbox, the baseplate should change colour.

However this is not the case

As you can see in this clip the baseplate stays red and never turns green, even after I touch one of the dummies.
Here is what the hitbox is meant to look like

Hitbox

image
image536×664 46 KB

Script 
local player = game:GetService("Players").LocalPlayer
local Chr  = player.Character or player.CharacterAdded:Wait()
local root = Chr:WaitForChild("HumanoidRootPart")

local function checkHit()
	
	local cf = root.CFrame + Vector3.new(0,0,-1.5)
	local size = root.Size + Vector3.new(0, 0, 20)
	local PlayerHitBox = workspace:GetPartBoundsInBox(cf, size)

	for i,part in pairs(PlayerHitBox) do
		if part.Parent:FindFirstChildWhichIsA("Humanoid") and not Chr then
			workspace.Baseplate.Color = Color3.new(0.423529, 1, 0.384314)
		else
			workspace.Baseplate.Color = Color3.new(1, 0, 0.0156863)
		end
	end
end
      
game:GetService("RunService").Stepped:Connect(checkHit)

Edit: I added the not Chr because I dont want the hitbox to interfere in case it touches yourself

Any help would be appreciated, thanks

#2

Are you trying to check if part belongs to Chr? not Chr just means the inverse of Chr, which is truthy because Chr is not nil or false. So not Chr is always false, so the if block never runs only the else block.

Did you mean if part.Parent:FindFirstChildWhichIsA("Humanoid") and not part:IsDescendantOf(Chr) then ?

Another thing, even if a valid part is found during the for loop, what happens if there are more parts in the hit box? On the second time around the loop it might overwrite the color that you set on a previous loop, which is probably not what you want. Seems like you want to check if any of the parts are valid, and then set the color based on that. Try

local otherCharacterTouching = false
for _, hitPart in ipairs(PlayerHitBox) do
    --Use "early continue" instead of nested if statements or if statements with complicated conditions
    if not hitPart.Parent:FindFirstChildWhichIsA("Humanoid") then continue end
    if hitPart:IsDescendantOf(Chr) then continue end
    
    otherCharacterTouching = true
    break --This is optional, just a slight optimization and also makes it clearer to the reader what we're trying to do. Omitting it won't break anything since the loop can never set the variable back to false.
end

if otherCharacterTouching then
    baseplate.Color = COLOR_1
else
    baseplate.Color = COLOR_2
end