Getting the degree amount to make 2 faces perfectly align each other

[kater3ds (katerCodes)]

Hey there! Basically I’ve been trying to get a number (basically degrees for rotation) to make 2 faces perfectly align / face each other.

Basically I have this table where I store the possible degree options

["Degrees"] = {
				["Front"] = 0,
				["Left"] = 270,
				["Back"] = 180,
				["Right"] = 90,
			},

The 2 faces / objects I want to align both have values inside of them looking like this:

StartConnection = "Front",
		EndConnection = "Back",

They correspond to the degree table.

I had issues with actually getting the perfect number to make the EndConnection of the previous tile and the StartConnection of the new tile / object align.

Here is an example of some connections if that helps:
Previous tile:
StartConnection = “Front”,
EndConnection = “Right”,

To place tile (new):
StartConnection = “Front”,
EndConnection = “Back”,

How it looks like:

How it’s supposed to look like:

Does maybe anyone know how I could achieve the thing I’d like to do?

[kater3ds (katerCodes)]

Yea help would be greatly appreciated!!

[VonsRevenges (VXN)]

Get the start and end connections for the old tile and another two for the new tile, and do this formula: (endDegree - startDegree) % 360, (get the degrees from the table of degrees you already have) and you should get the rotation angle:

local degrees = {
	["Front"] = 0,
	["Left"] = 270,
	["Back"] = 180,
	["Right"] = 90,
}

function RotateAngle(startConnection, endConnection)
	local startDegree = degrees[startConnection]
	local endDegree = degrees[endConnection]
	local rotateAngle = (endDegree - startDegree) % 360
	return rotateAngle
end

-- Example use:
local oldTile = {
	StartConnection = "Front", 
	EndConnection = "Right" 
}
local newTile = {
	StartConnection = "Front", 
	EndConnection = "Back"
}

local rotateAngle = RotateAngle(oldTile.EndConnection, newTile.StartConnection)
print("Rotation Angle: " .. rotateAngle)

[kater3ds (katerCodes)]

Weeell that didn’t quite work out.
As seen the corner is still off and the straights are facing the wrong way (are 180 degrees turned too much).

That’s my code:

local function RotateAngle(startConnection, endConnection)
			local startDegree = directions.Degrees[startConnection]
			local endDegree = directions.Degrees[endConnection]
			local rotateAngle = (endDegree - startDegree) % 360
			return rotateAngle
		end
		
		local newRotation = RotateAngle(previousBackEnd, selectedFrontEnd)

[VonsRevenges (VXN)]

Well for the negative degrees, add 360 to the result. (check if its less than 0 to know if its negative)

[kater3ds (katerCodes)]

That didn’t change anything…

local function RotateAngle(startConnection, endConnection)
			local startDegree = directions.Degrees[startConnection]
			local endDegree = directions.Degrees[endConnection]
			local rotateAngle = (endDegree - startDegree) % 360
			
			local negativeAdd = 0
			if rotateAngle < 0 then
				negativeAdd = 360
			end
			return rotateAngle + negativeAdd
		end

Was my code correct or did I do a mistake?

[VonsRevenges (VXN)]

I meant add 360 not to set it to 360.

[kater3ds (katerCodes)]

Huh? I am adding 360 (negativeAdd) to the “rotateAngle” var which is the result. NegativeAdd is 0 if the result isn’t negative so uhhh what?

[VonsRevenges (VXN)]

My bad i didn’t notice that you added that on the return

[kater3ds (katerCodes)]

Yea so… Any ideas why it couldn’t work? Maybe it would be a good idea to step away from that degrees table and just find a way to make the back end of old tile and front end of new tile align?

[VonsRevenges (VXN)]

You mean like this:

local connections = {
    ["Front"] = "Back",
    ["Left"] = "Right",
    ["Back"] = "Front",
    ["Right"] = "Left",
}

[kater3ds (katerCodes)]

Not sure… I was considering maybe finding a whole new method (what would that table you just suggested even do, it’s just strings…).

[kater3ds (katerCodes)]

I fixed it! I just hardcoded every possibility . Thanks for the help though!!