--- a/ai/utilities.d	Wed Mar 25 11:28:25 2009 -0400
+++ b/ai/utilities.d	Wed Mar 25 14:44:47 2009 -0400
@@ -31,6 +31,7 @@
 module openmelee.ai.utilities;
  
 import tango.math.random.Kiss : Kiss;
+import blaze.common.bzMath : bzVec2, bzDot;
 
 float scalarRandomWalk(float initial, float walkspeed, float min, float max) {
 	
@@ -40,6 +41,19 @@
 	return next;
 }
 
+// return component of vector perpendicular to a unit basis vector
+// IMPORTANT NOTE: assumes "basis" has unit magnitude(length==1)
+bzVec2 perpendicularComponent(bzVec2 vector, bzVec2 unitBasis) {
+    return (vector - parallelComponent(vector, unitBasis));
+}
+
+// return component of vector parallel to a unit basis vector
+// IMPORTANT NOTE: assumes "basis" has unit magnitude (length == 1)
+bzVec2 parallelComponent(bzVec2 vector, bzVec2 unitBasis) {
+    float projection = bzDot(vector, unitBasis);
+    return unitBasis * projection;
+}
+        
 // ----------------------------------------------------------------------------
 // classify a value relative to the interval between two bounds:
 //     returns -1 when below the lower bound
@@ -52,6 +66,10 @@
     return 0;
 }
 
+float square(float x) {
+    return x * x;
+}
+        
 T randomRange(T = int) (T min, T max)
 {
     return min + Kiss.instance.natural() % (max + 1 - min);