Curve Tracing

Upload Image
Datapicker can be created inside a project via Add new in the context menu of project/folder or in the main toolbar. After that a new image can be added and can be changed via Plot in the corresponding dock widget.
After uploading image different zooming options can be used from the context menu/datapicker toolbar to change width and height of image. Image can also be rotated to an angle using Rotation in the "edit" section of dock widget. After this user have to set axis points.

Symbols
Symbols are the points that can be drawn over image of datapicker. Symbols can be directly created by mouse right click over the image. Symbols are mainly of two types, with and without error-bar depending on the type of curve they belong.
Every curve of datapicker can have its own symbol style that can be changed in the Symbols section of dock widget. "SelectAndMove" mouse mode can be used to select multiple points/symbols and can be moved by using navigation keys.

Axis Points
Axis Points are the set of three reference points over image of datapicker. These points can be set via Set Axis Points in the context menu of datapicker. After selecting points over image user have to update their coordinate system type via Plot Type and logical positions via Ref. Points in the dock widget.

Datapicker Curve
Datapicker-Curve can be created inside datapicker via New Curve in the context menu of datapicker. A curve can have different types of X and Y errors (No-error, symmetric, asymmetric). This depends on the type of errors dock widget of datapicker have at the point of creation.
Every curve object contains all the curve points (hidden) and a spreadsheet that contains logical positions of all its curve points, and provides options to update spreadsheet and to toggle visibility of its curve points using the context menu. Mode Set Curve Points in the context menu of datapicker should be selected in order to create curve points.
Multiple curve can be created for same datapicker. The created curve points always correspond to the active curve of datapicker which can be changed via Active Curve option in the context menu and dock widget of datapicker. Every curve of datapicker can have its own symbol style that can be changed in the Symbols section of dock widget.

Curve Segments
Curve segment for datapicker can be created over image by switching mode to Select Curve Segments in the context menu of datapicker. A segment is a selectable object over image which can be selected by mouse right click over it.
Segments are created by processing of image on the basis range of colour attributes in order to automatically trace curves. To improve results these range and types of colour attributes can be changed in the "edit" section of dock-widget. Dock-widget also provides options to switch among processed image and original image, and to set the minimum possible length of segments.
Once a segment is selected it will create curve points over it with a minimum specified distance among them. The minimum specified distance among the points can be changed in the dock widget of datapicker. User might have to select the segments again in order to observe the changes.