~~NOTOC~~
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====== BounceEdgeCollision ======
BounceEdgeCollision(<-currentPosition <-lastPosition <-reflectionScale) ->newLastPosition ->newPosition

===== Description =====
Calculates a bounce off of the edge of the map. Given two positions that represent the current and previous positions of a moving object, this call will calculate a new position and previous position
for the moving object. The new positions will calculate a colllision with any mape edge and generate a reflection so that the moving object will appear to have bounced off of the edge.\\
   * currentPosition:  A vector for the current position of a moving object
   * lastPosition:  A vector for the last position of a moving object. The currentPosition-lastPosition is used to determine a vector of motion for the object.
   * reflectionScale: A float that controls the scale of the reflection. A value of 1 makes the reflection the same as the input velocity. A value less than 1 damps the reflection and a value greater than 1 amplifies the reflection.

Note that if there is no edge collision then the 'w' (the last) position in the resulting vectors will be 0 (false). It will be 1 if there was a collision.
Also note that if there is no terrain collision then the resulting newPostion and newLastPosition will be equal to currentPosition and lastPosition.

===== Examples =====
<code 4rpl>
BounceEdgeCollision(<-position, <-lastPosition, 1) ->nlp ->np
if (<-np.w)
   <-np ->position
   <-nlp ->lastPosition
endif
</code>
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