:GetBoundingBox() for tools and accessories (and possibly more)

At the moment, it’s annoying to become aware of the bounding box of a tool/accessory’s size and CFrame. You would reparent everything inside of these objects to a dummy model, and call the :GetBoundingBox() of that model.

I have needed this method when working with tools and wanting to reparent the parts inside of the tool to workspace so it’s placed wherever the player ordered to after removing it from the player’s inventory.

It will be nice to have this method for these objects too, as they act as a container for physical objects just like Models.

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In lieu of having said API, the following (well optimized) code from the Studio draggers can be used to compute a bounding box without making a temporary model:

local function computeBoundingBox(basisCFrame: CFrame, allParts: {BasePart}, allAttachments: {Attachment})
	local inverseBasis = basisCFrame:Inverse()
	local xmin, xmax = math.huge, -math.huge
	local ymin, ymax = math.huge, -math.huge
	local zmin, zmax = math.huge, -math.huge

	local terrain = Workspace.Terrain

	for _, part in ipairs(allParts) do
		if part ~= terrain then
			local cframe = part.CFrame
			local size = part.Size
			local sx, sy, sz = size.X, size.Y, size.Z

			-- Calculation for bounding box in the space of basisCFrame1
			local localCFrame1 = inverseBasis * cframe -- put cframe in our local basis
			local _, _, _,
				t00, t01, t02,
				t10, t11, t12,
				t20, t21, t22 = localCFrame1:components()
			local hw = 0.5 * (math.abs(sx * t00) + math.abs(sy * t01) + math.abs(sz * t02))
			local hh = 0.5 * (math.abs(sx * t10) + math.abs(sy * t11) + math.abs(sz * t12))
			local hd = 0.5 * (math.abs(sx * t20) + math.abs(sy * t21) + math.abs(sz * t22))
			local x, y, z = localCFrame1.X, localCFrame1.Y, localCFrame1.Z
			xmin = math.min(xmin, x - hw)
			xmax = math.max(xmax, x + hw)
			ymin = math.min(ymin, y - hh)
			ymax = math.max(ymax, y + hh)
			zmin = math.min(zmin, z - hd)
			zmax = math.max(zmax, z + hd)
		end
	end
	for _, attachment in ipairs(allAttachments) do
		local localPosition = basisCFrame:PointToObjectSpace(attachment.WorldPosition)
		local x, y, z = localPosition.X, localPosition.Y, localPosition.Z
		xmin = math.min(xmin, x)
		xmax = math.max(xmax, x)
		ymin = math.min(ymin, y)
		ymax = math.max(ymax, y)
		zmin = math.min(zmin, z)
		zmax = math.max(zmax, z)
	end

	local boundingBoxOffset = Vector3.new(
		0.5 * (xmin + xmax),
		0.5 * (ymin + ymax),
		0.5 * (zmin + zmax)
	)
	local boundingBoxSize = Vector3.new(
		xmax - xmin,
		ymax - ymin,
		zmax - zmin
	)

	return boundingBoxOffset, boundingBoxSize
end
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