Thanks for your question.
Yes, CAM Library can also allow you to perform editing (transformations), selection, add objects, and more.
For viewing you can ask CAM Library to generate a screen capture (i.e rectangular snapshot of the objects) and then display that image to your users. Essentially that's how our Gerber viewers (DFM Now and FAB 3000) work. For example if someone wants to zoom into a certain area, we simply generate an image of that area, and then display it to the user; this is repeated every time a new view is requested. https://numerical-help-guide.s3.amazonaws.com/camlib3/html/group__display__api.html#gae0caf8bab3f85ff76efbac661dad520f