WIP matrix & rotation lua APIs

games/devtest/mods/unittests/rotation.lua

@@ -0,0 +1,67 @@
+local function describe(_, func)
+	func()
+end
+
+local function it(section_name, func)
+	print("Running test: " .. section_name)
+	func()
+end
+
+local function assert_close(expected, actual)
+	assert(expected:angle_to(actual) < 1e-4)
+end
+
+describe("constructors", function()
+	it("identity", function()
+		local rot = Rotation.identity()
+		assert.same({0, 0, 0, 1}, {rot:to_quaternion()})
+	end)
+	it("quaternion", function()
+		local rot = Rotation.quaternion(0, 0, 0, 1)
+		assert_close(rot, Rotation.identity())
+	end)
+	it("axis angle", function() end)
+	it("axis-angle shorthands", function()
+
+	end)
+end)
+
+describe("composition", function()
+	it("is the identity for an empty argument list", function()
+		assert_close(Rotation.identity(), Rotation.compose())
+	end)
+	it("is the same rotation for a single argument", function()
+		local rot = Rotation.x(math.pi / 2)
+		assert_close(rot, rot:compose())
+	end)
+	it("is consistent with application", function()
+
+	end)
+end)
+
+local function random_quaternion()
+	local x = math.random()
+	local y = math.random()
+	local z = math.random()
+	local w = math.random()
+	return Rotation.quaternion(x, y, z, w)
+end
+
+describe("inversion", function()
+	it("random quaternions", function()
+		for _ = 1, 100 do
+			local rot = random_quaternion()
+			assert_close(Rotation.identity(), rot:inverse():compose(rot))
+			assert_close(Rotation.identity(), rot:compose(rot:inverse()))
+		end
+	end)
+	it("inverts the angle", function()
+		for _ = 1, 100 do
+			local rot = random_quaternion()
+			local axis, angle = rot:axis_angle()
+			local inv_axis, inv_angle = rot:inverse():axis_angle()
+			assert(axis:distance(inv_axis) < 1e-4)
+			assert(math.abs(angle + inv_angle) < 1e-4)
+		end
+	end)
+end)