Help me to find the half point of ZigZag segment line

 
Please help me to find and mark on the a zigzag mq4  indicator the half point of an any ZigZag segment line, (like 1-2, or 3-4, or 4-5) and the time of this half point. Can someone that are more smart than me to make such an ZigZag indicator ? Please ?
Files:
HALF_POINT.png  20 kb