Repeated visual bugs

I've been having this issue for several months now, or rather ever since the new map was released but every couple of games or so the map has noticeable issues that sometimes aren't that bad, but other times are actually very interfering as sometimes they put a sort of tent over a large portion covering the map. This happens around maybe 1 out of 3 games and this issue so far for these past months just hasn't gone away even after repairing the client, uninstalling League, and even deleting all of its files off my computer. Most of them are very devastating and very hard to play with the bugs as it completely obstructs your view of certain areas. It only seems to do this in the jungle though.

Aside from this as well I've noticed that pretty much every game at some point a random white figure flickers on the screen for half a second. This happens completely randomly and I can't screenshot or even react to it.

Also I have not messed with any of the League files at all. I haven't done any form of modifications to the client or game at all.

The first screenshot isn't anything horribly bad but I thought I'd include it anyway since the trees stretching happens often.

I am using a Radeon HD 7870 graphics card.