@Gigit Not even improved in time with the little planting they have, I don't know why they didn't do something like the outdoors enclosures of realm of the red ape are Chester.
A more active orang than Tiga (and dear old Rajang) would make short work of that greenery and would probably be bored enough to wreck the climbing frames. The only thing you can say about it is that it's an improvement on what they had before, and that is very faint praise.
It really is an uninspiring enclosure, the indoors is better but still not groundbreaking. I found the aquatic displays in the building to be of a much higher quality, in fact they were probably the highlight of the building.
@Gigit From memory the greenery is growing from a sort of pond(I think). It is a hideously ugly enclosure with that wall most of the way around- you can only view from the little balcony area at one end- I think the entrance road runs behind the wall so that may be why. Ugh. Hate it... Like something from the 1960's.