diff --git a/builtin/common/misc_helpers.lua b/builtin/common/misc_helpers.lua
index 0b60812..e1dc289 100644
--- a/builtin/common/misc_helpers.lua
+++ b/builtin/common/misc_helpers.lua
@@ -212,6 +212,17 @@ function math.hypot(x, y)
 	return x * math.sqrt(1 + t * t)
 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 get_last_folder(text,count)
 	local parts = text:split(DIR_DELIM)
diff --git a/builtin/common/vector.lua b/builtin/common/vector.lua
index 88ccfe6..e9ed3aa 100644
--- a/builtin/common/vector.lua
+++ b/builtin/common/vector.lua
@@ -39,6 +39,14 @@ function vector.round(v)
 	}
 end
 
+function vector.apply(v, func)
+	return {
+		x = func(v.x),
+		y = func(v.y),
+		z = func(v.z)
+	}
+end
+
 function vector.distance(a, b)
 	local x = a.x - b.x
 	local y = a.y - b.y