Hi I'm new to the forums! I want to know how hard it is to create a 3-D world in which someone can walk around in. Nothing more, just the world and you, I'm not trying to make an MMORPG or anything, but I've always wanted to shape a world of my own, and I just want to know how hard it would be to do it.

Thank you!

With Unity3D it is fairly easy from a technical point of view since it handles the basics for you, actually building the world and filling it with interesting and good looking content takes time, effort and artistic talent.

If "the world" is just a horizontal plane spanning to infinity, I guess it'd be pretty easy. It's when you start adding stuff in that it gets more complicated

tl;dr define world

If you want to do the entire programming by yourself a small terrain with some vegetation is simple enough to set up, but it still requires skill and talent to make it believable
As soon as your world starts to get larger and more varied you'll run into quite some technical problems, you'll want to maintain detail, or at least the illusion of detail, at all ranges and all distances without having to send a massive amount of resources to your rendering system. World rendering systems like you see in games like Skyrim are quite sophisticated and implement various advanced techniques to maintain this level of detail.

If you're going for the "do-it-yourself" approach I must say I think this is a rather nice goal to set for yourself, but I don't think it's one you should try to pursue from the very beginning. Get familiar with basic graphics programming concepts first before going into advanced territory.


If you want to use third party tools it will save you the trouble of having to implement such a system yourself, but you'll still need quite some artistic skills to get a believable world. Also keep in mind that there are many techniques out there to do world/terrain rendering, so you'll have to make a list of requirements for your world and find a tool which can meet them.
A couple of these requirements could be the scale of your world, surface material variety, vegetation variety, etc.

Oh and if I were to add something to Unity3D, could I? Like, for example if Unity3D doesn't let you have characters that can climb walls like in Assassin's Creed, could I somehow implement it (for the sake of the example pretend I am a very experienced coder) or would the person who made Unity3D not let you?

Unity doesn't handle any advanced things for you so you are expected to write your own code. everything except the renderer can be changed with scripts in the free version. (In Pro you also get access to the renderer and can use native plugins to write your own custom renderer if you really want to)

climbing a flat wall can be done using a static animation and thus is fairly easy with Unity(Creating good animations for it is hard though), dynamic animation is easy as long as its physics based (ragdolls for example), custom dynamic animation is hard regardless of what engine you use but Unity gives you access to everything you need so it can be done, (The more complex things you try to do the harder it gets ofcourse).