hide/display:none slide when not active in full presentation mode?

[patrickhlauke]

Just wondering if there's a reason why, when presenting, slides are "stacked" rather than using display:none to remove all but the .active slide. The current behavior, combined with large slide shows with lots of high-res images (which yes, admittedly aren't a fantastic idea for performance) results in heavy image decode thrashing in current Chrome (see https://twitter.com/patrick_h_lauke/status/911962086875521026 and https://bugs.chromium.org/p/chromium/issues/detail?id=768799).

I've patched this in my presentation here, but wondering why that's not default behavior for shower.

patrickhlauke/getting-touchy-presentation@aa9bd6e

[pepelsbey]

I did it mostly to prepare slides for possible animations. But I never managed to implement it. In fact, I even hate such slide animations. So if you say it would make performance better, I’ll try to make it a default behavior.

[pepelsbey]

Right, there’s a problem: with display: none|block animated special effects like growing and shrinking shouts stop working, see next 2 sliles in fullscreen mode.

Here’s the code for animation. I’m not exactly sure how to make it work with display: none

[pepelsbey]

Here’s the demo and it seems that no animation could be triggered on a slide after display: none to block switch.

[patrickhlauke]

wonder if using CSS animation instead of transition could work...

[patrickhlauke]

Of course, this makes it more cumbersome, but it seems to work - see demo https://codepen.io/patrickhlauke/pen/veRyyB?editors=1100

[pepelsbey]

Yay! Will release Ribbon and Material versions with display: none this week. Thank you :)

[pepelsbey]

There’s a problem: when something’s display: none it doesn’t take part in counters. Meaning, that I can generate slide numbers only in list mode, in full mode every slide will be 1. Any idea what to use instead of display: none to achieve the same perf results?

[patrickhlauke]

i've actually switched to visibility:hidden ... does that also cause the same counter issue? patrickhlauke/getting-touchy-presentation@7180a69

[patrickhlauke]

also, the perf problem seems to have been fixed (not yet in stable, but at least in canary), so you may get away with not actually fixing anything in the worst case...

[pepelsbey]

If you wait long enough any perf problem would go away :D

[patrickhlauke]

[pepelsbey]

There’s a problem with visibility: if you use it for something else (like class="next" steps) it will override parent’s visibility and pop-up over the current slide from somewhere else.

[pepelsbey]

Good old clip: rect(0 0 0 0) to clip: auto switching works fine too.