So, this code library was created to show one possible way of getting that image which is rendered by the client browser, on the server, precisely because there is some demand for it, and we do take it seriously.
To continue with server-side rendering - the RadChart control is still available in theTelerik.Web.UI assembly and you can still use it (as explained in the blog post that announced that it is obsolete). Its documentation is still live, its demos remain in the LiveDemos project you can download from your account, its forum is still live even though we do not monitor it. RadChart is marked as obsolete because it has not been actively developed for several years and this makes sure this messages is clear enough. The control is in just about the same state it was three years ago and you can keep using it if pure server-side chart creation is an important objective.
Ultimately, the UI for ASP.NET AJAX suite is a user interface toolset, not a reporting engine (we do have the Telerik Reporting for that, and it also offers charts and can save files on the server). Thus, moving towards client-side operation is a natural step for the suite.
I do understand that in some cases the suite will not offer every feature you would need, and we do try to add the ones most requested so we can aid you in your work. This is why this code library exists, and why RadChart remains in the assembly.
@Henrik - I am glad that our software is helping your in your work. We will try to examine and showcase an integration with a library like PhantomJS that will result in pure server-side operation from the end user point of view (even though it would run a browser on the server).
@Matt - we are already in touch with you via your account managers and I would suggest continuing the discussion there if you have outstanding questions.
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