Support reveal's lazy loading feature
I use a lot of images and iframes, so this is essential. It ought to be the default (and maybe it is).
We use reveal.js’ lazy-loading with the default viewDistance setting (3) for all Slides presentations. I don’t think it makes sense to expose viewDistance as a setting since it’s not something most people need to think about.
Max Rahder commented
You'd need to let us set the viewDistance preload count too, to avoid getting a load delay on every page.