TrafficControl: Possible Areas for Optimization

When designing software, it is often important to compromise between simplicity and performance. Optimizing source code can improve performance, but it will also make the software more complex and harder to debug and maintain in the future.

For TrafficControl, I've identified some areas where I can optimize it, if that will be needed later on:

• Accessing QML items from C++: In the QML slot, the JavaScript is iterating over the QML object tree until it finds the item with the corresponding objectName. It should be possible to save the index for the particular QML item when creating it, and save the index so that C++ objects can access the QML item directly. 
  
• Updating position of trains on tracks: Currently, the program is iterating through all coordinates to find wich two consecutive coordinates to interpolate between for every update. It should be possible to rmake the program remember the last coordinate and search from there.
• Implementing model/view for the QML map: Explore whether this will improve the performance.

Before doing all that, I'll review, refactor and clean up the code.