Add workaround for some (apparently broken) gcc versions

Thanks to Robin Watts and Vladimir Murzin.

Move "button" to the bottom

Allow embedding

Sorting

Unimaginably fugly, but does work it seems

Sync with upstream

Sync with upstream

Tweaks for intel cards

Reduce default texture count (given that slice height has increased)
and turn on PBO.

Cosmetics

Cosmetics

Shrug