Hi Jonathan,
Thank you for choosing Syncfusion products.
We would like to inform you that your requirement can be achieved by using Series Annotation and this will position the annotations in ChartAxis coordinates. Please find the following UG link for ChartSeries annotations (Chart Controls > Chart > Concepts and Features > Annotations > Annotations At X-Y Coordinates).
http://help.syncfusion.com/User%20Interface/WPF/Chart
Also we would like to inform you that we have methods to convert the device coordinates to axis coordinates and vice versa. Please find the code snippet below.
Code Snippet:
[C#]
//Convert Point to Value
double valx = chtarea1.PointToValue(chtarea1.PrimaryAxis, mousePoint);
double valy = chtarea1.PointToValue(chtarea1.SecondaryAxis, mousePoint);
//Convert Value to Point
Point pt = new Point(chtarea1.ValueToPoint(chtarea1.PrimaryAxis, valx), chtarea1.ValueToPoint(chtarea1.SecondaryAxis, valy));
The attached sample tooltip shows the result of these method while moving the mouse.
Please let us know, if you have any queries.
Thanks,
Rajkumar B R
CS_24a2c842.zip