So, you might be wondering “Which file formats does RibbonX support?
RibbonX operates on bitmap objects in code, not on files on the disk. It’s the add-in which actually loads the files and returns the bitmap objects to RibbonX. Thus, an add-in can use whatever file format it wants when it is loading its images.A better way to think about the question might be, “What file formats do the libraries I’m using support?” Unfortunately the answer can be a bit complicated because the libraries for different languages and technologies (VBA, C++, .NET, etc.) vary widely in their support for image file formats and alpha channels. GDI+ can be used from both native C++ code as well as managed C#/VB.NET code and it supports loading all common file formats, so it’s the recommended library to use to load images.If you’re using VBA, you might think you’re out of luck since the native VB APIs like LoadPicture() don’t support PNG files, and you can’t use GDI+ without mucking around with importing Win32 functions and types. Fortunately, VBA add-ins live in the new Open XM
