I will chip in a bit; another people may present even higher solutions.
Contemplating the RAM utilization
Graphics typically influence the video RAM (the VRAM), not the system RAM as you appear to say. Usually, computer systems can have way more system RAM than video RAM. Additionally, VRAM will typically be occupied extra by textures than by precise vertices that compose the mesh. In case you have a low-poly mesh and a hi-res texture, you can bust your (V)RAM.
will or not it’s higher to make use of low – poly terrain
We will not reply that.
What sort of sport do you need to make? Would it not make sense to have a low-poly terrain and a hi-poly principal character(s)? Relying on the sport, you’ll be able to “cheat” and cargo dynamically solely the terrain that’s seen to the digital camera and what’s instantly surrounding it; you unload what’s not seen, releasing up the reminiscence for what issues.
Take into account that utilizing low-poly terrain will be a bonus w.r.t. physics. The much less polygons there are, the less complicated the collision checking (the place a totally flat floor is the only).
It is a balancing act between all of your wants.
