I am currently having trouble getting started with writing an extension that shifts the viewer to a pdf view. More or less, the extension button in mind, when clicked/activated, makes the viewer look like the first image here, and when it is clicked again/deactivated, it reverts back to the regular 3D viewer.
I tried looking into the code in the above link but I don't understand where the modelDocument object came from. I am using the Forge Viewer completely offline, so I am not dealing with any URNs, authentication mechanisms, etc. I already wrote extensions that can change the 3D model in the browser in some way, but this new extension is different.
Thank you in advance!