Enhance iOS Diagram Engine (Swift 4.2, Sprite Kit)

This project should expand an existing basic Diagram Engine to support the features listed below. It should be written in Swift 4.2 and use Sprite Kit. The full source code should be delivered and a simple playground should be provided as demo. The source should be implemented as "framework" to be easily included in other projects. The engine should be able to: - Initialize with a specific X/Y range (support positive and negative values on Y axis, X axis are objects with date and time) - Draw multiple lines of data in one diagram and interpolate lines - Incoming data might have changing intervals. - Each line might have different time stamps of the data - Y Scale should adjust if currently visible values are out of visible range, and go back to the specified range if everything is in range) - Possibility to add markers (=Dots with X/Y coordinates and specific color + Label) - Possibility to add horizontal Lines of specific color - Possibility to add a Y-Background Fade (should be customizable in colors and Range -> (Range A MAX (solid color from visible min up to a-max), Range B MIN-MAX (solid color from min to max), Range C MIN (solid color starting from min up to visible max) - and gradient in between the ranges) - this needs to zoom with the auto scaling of Y data as described above - Functionality to Show/Hide each individual Graph - Support Gestures to scroll and Zoom smoothly on the X-Axis - Support Live Update of the Data (i.e. auto-scroll if scrolled to the end) - Support Touch to Show Values of a specific Timestamp (i.e. stop auto-scroll but keep adding data to the end) - Possibility to have multiple Diagram Views visible at once (i.e. insert multiple views into one view controller), and link their X-Axis together - i.e. if you scroll/zoom on one Diagram, the second should follow state