Add roam plugin.

[kdxcxs]

Add roam plugin to allow the user to change the view freely.

[henrikingo]

Thanks kdxcxs!

This is very impressive. I have implemented something similar in impressionist however, unlike you I did miss CS computer graphics classes and you can tell the difference. I was impressed to read your clean implementation.

I have a small number of impress.js specific changes requested.

In addition, it could be nice to advertise this feature in some of the demo presentations. The classic-slides demo is intended to showcase most features, so you could add text somewhere - maybe to the last overview step - to advertise roam plugin. In addition it seems the 3D-rotations demo is kind of topical here?

[kdxcxs]

Thanks henrik. I'm really happy you like the idea and it's an honour to contribute to such a cool project!

Actually I'm not sure if it's better to move just the view instead of the active step.

Also, I couldn't come up with a impressive way to advertise it for now as I want to keep the demo cool and clean. I'll do my best.

[henrikingo]

Actually I'm not sure if it's better to move just the view instead of the active step.

Of course. I just meant the overview step could have the text somewhere. Or it can just be a regular slide.

Also, I couldn't come up with a impressive way to advertise it for now as I want to keep the demo cool and clean. I'll do my best.

I can do it separately if you don't feel like it.

[henrikingo]

Ah, sorry. I should have pointed to this in my last review, but I had forgotten how exactly to do this. Please use

gc.pushCallback(my_function);

impress.js/src/lib/gc.js

Line 60 in f68e5ff

var pushCallback = function( callback ) {

... to register a function that is called as part of impress().tear().

Example:

impress.js/src/plugins/progress/progress.js

Line 22 in d0c427f

gc.pushCallback( function() {

[henrikingo]

Oh, and please run npm run all and then include js/impress.js in your commit. Due to backward compatibility impress.js has the built file directly in the git repo.

[henrikingo]

Hi, again... So I downloaded your branch and tried it a bit. It works and is really cool, but...

I think this is what you referred to as well: It probably makes more sense not to move the current step and rather move the "view". Impress calls it the canvas element, in Impressionist I call it "camera". Anyway, this is how you get to the canvas element:
https://github.com/henrikingo/impressionist/blob/788e6d05e50287ea52911ae485a27054a46c3516/src/plugins/camera/camera.js#L82

It's a <div> inserted dynamically between the div#impress element and the .step elements. Moving the canvas can be done with exact same functions as you have, except I believe you have to move in the opposite direction compared to what you are doing now.

Moving the canvas means that I can "roam" around the entire presentation, but the slides don't move in relation to each other.

Minor: For the left hand, I wonder if it would be more natural to use keys a-f, w-s, e-d instead? (Corresponding to left-right, up-down, in-out, respectively.) The way you have it now, I would expect w-s to move up-down. But this is subjective, it's equally correct the way you've implemented it.)