local module = {}
setmetatable(module, {__index=_G}
setfenv(1, module)


--===== collision =====--

Geom = {}
Geom.__index = Geom


function Geom.new(_, type, params)
	local self = {}
	self.type = type
	self.params = params
	setmetatable(self, Geom)
	return self
end
setmetatable(Geom, {__call=Geom.new})


function Geom.renew(geom)
	return ode.GeomGetData(geom)
end


local function instantiateSphere(space, params)
	local geom = ode.CreateSphere(space, params.radius)
	return geom
end


local function instantiatePlane(space, params)
	local geom = ode.CreatePlane(space, params.a, params.b, params.c, params.d)
	return geom
end


function Geom.instantiate(self, space)
	if self.type == "sphere" then
		self.geom = instantiateSphere(space, self.params)
	elseif self.type == "plane" then
		self.geom = instantiatePlane(space, self.params)
	else
		error(string.format("bad geom type: %s", self.type))
	end
	ode.GeomSetData(self.geom, self)
	return self
end


function Geom.setBody(self, body)
	ode.GeomSetBody(self.geom, body.body)
	return self
end