# Tixus

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Yeah. Forgot to mention that my heightmap was in fact 2048. Going higher than that for better geometry would mean even more quads that I'm sure my computer wouldn't be able to handle. And with that, I think I'm going to build the mountains out of static meshes. No more talk of heightmaps. I'm going to be heading away for the holiday, so I'll probably have more questions in a week or so. Thanks for all the guidance so far.

Thanks for the info about triangles. I was always wondering about that. Now for my concern with the logistics of the world I'm trying to build: The size of the world is roughly 2 square kilometers (2048x2048). While I agree that using heightmaps and terrain is the ideal way to build and store the world, there are some serious issues with the numbers I'm running into. If each pixel represents a polygonal space on the map, then just using a 2048x2048 bitmap would use more than 4 million quads. Each quad would occupy a square-meter of area, which is too large. Subdividing and increasing the plane segments would help this, but it would turn into more quads than my system can handle...and that's without converting to an editable poly. After some reading (Of some very vague sources, I really couldn't find much), I'm willing to go up to between 300-500 thousand triangles for the world. What I could really use, but unfortunately aren't available, are some reference numbers to poly counts of environments in existing open-world games...but all of my searches just lead to character poly counts. I guess low poly scenes I could actually load and look at in max would also help me out, but again, I can't seem to find much of anything.

Made a heightmap I was pleased with, and used it for the world terrain. Might have skipped a few essential steps. At a distance, the world looks roughly like what I was hoping for, but up close, things are pretty ugly. Considering that each square is vastly larger than the player in size, I don't think I can get away with the zig-zagging and stretched polys that seem to be a prominent feature in terrain modeling. Reference: http://img809.imageshack.us/img809/6744/heightworld1.png http://img6.imageshack.us/img6/8240/arrghh.png Those zig-zagging polygons are the same problem I ran into earlier, only now I fear I have less control than when I extruded. I've considered two approaches: 1) Use splines to create static meshes of every mountain. Would give me the smoothness I want, but there are always going to be that N-sided polygon on the top, no matter how I drag in the edges and cut. But all game engines I know of use triangles anyway, so is it an issue if I end up with a bunch of quads and a few stray triangles? 2) Break the map up into a bunch of 512x512 regions (This'll require some simple reorganization of the layout). Then build separate heightmaps with a higher polygon resolution to try and get rid of the jagginess. But it comes with some big drawbacks--I don't particularly like how terrain tends to use inclined polygons to approximate straight surfaces, leading to some serious stretching of textures. Also, I don't know a thing about dynamic terrain loading in Unity or UE3, but I get the feeling I might have to start building my world with "loading regions" in mind. I'm not entirely sure what how many polygons I should be budgeting for this kind of endeavor. In an open-world game, how many polygons typically make up each map? I assume they split the world up into smaller regions, on account of trying to model an entire world would be too intense on hardware.

Thanks Kryzon. The advice is good, and I've been thinking about using heightmaps. My main concern is that it'll get rid of the straight-upward jutting nature of the walls, and the flatness of the surrounding ground Since I'm going for something a little cartoony and not so realistic, I want to keep some of the flatness on the terrain you can travel on. But with that being said, I'll definitely look into heightmaps for the mountain areas you can't travel on. What I'm thinking of is a simple plane of all travel-able regions (So I can make it as flat or consistently inclined as I want), and then have the mountains be their own layer that poke through the ground.