Add new vector utils (ceil, sign, abs, random_in_area) (#14807)

builtin/common/math.lua

@@ -0,0 +1,41 @@
+--[[
+    Math utils.
+--]]
+
+function math.hypot(x, y)
+	return math.sqrt(x * x + y * y)
+end
+
+function math.sign(x, tolerance)
+	tolerance = tolerance or 0
+	if x > tolerance then
+		return 1
+	elseif x < -tolerance then
+		return -1
+	end
+	return 0
+end
+
+function math.factorial(x)
+	assert(x % 1 == 0 and x >= 0, "factorial expects a non-negative integer")
+	if x >= 171 then
+		-- 171! is greater than the biggest double, no need to calculate
+		return math.huge
+	end
+	local v = 1
+	for k = 2, x do
+		v = v * k
+	end
+	return v
+end
+
+function math.round(x)
+	if x < 0 then
+		local int = math.ceil(x)
+		local frac = x - int
+		return int - ((frac <= -0.5) and 1 or 0)
+	end
+	local int = math.floor(x)
+	local frac = x - int
+	return int + ((frac >= 0.5) and 1 or 0)
+end