Simple Question : 3D Graphics Engines

[isaiahk9]

Title is kinda unspecific, allow me to expand upon it :
I know very little about 3D graphic engines - basically all I know can be summarized that I know they play a role in making 3 dimensional graphics for video games/other applications. So, I was curious about a couple things :
What exactly is a 3D engine - ex. Unreal Engine. Is it software for the computer, or something similar?
How is the 3D engine connected to an application. Like how does a 3D model come out to something like this : http://www.youtube.com/watch?v=rxa5wWqn4CA&feature=related.
What programming languages can support 3D engines?
How do you get to 3D graphicallize with a 3D engine - like if it is done with computer software, how does one get the software, or etc.
And what insane times does it take to make a 3D model. For instance, the link to the sonic model, how long would you guess it took just to make the model, and then to program it (in months, or years (I really have no idea))?

Just curious, can anyone answer my ponderings?
thanx

[CodeMonkey2000]

First thing's first, 3D models are usually stored as vertices of each frame ( a file with a bunch of numbers). They are stored as binary files. Turing can open these files too. Some common file formats are .md2, .obj and .ply. It's just what you do with this information that's important. Game engines are usually just a library of functions and managers. They have functions to load models, display models, and place/scale models. To make models you need some sort of modeling program like 3DsMax, and save it in a file format that the engine can read. And as for how long it takes to make an engine, that all depends on how much you want it to do.

[andrew.]

I don't know much about 3D engines, but I think that game engines like Unreal Engine 3 handle things like models, textures, game code, physics, etc. I think the engine comes to developers in the form of software that you can use to build your game by importing source code and models and stuff.

Technically, any language can actually do 3D, even if it's really basic (even Turing can have a 3D engine).

To make models, most people use 3ds Max. You can model stuff with it. If you want to make animations, you can export those models to a program like Maya or Blender to animate it. I think you can also render scenes inside of 3ds Max.

That's about all I know about 3D engines. I hope the information I gave you is right. lol

[isaiahk9]

awe-inspiringly helpful. wait a minute, how can even Turing open these files? Is there a function, or is it a hodge-podge of different techniques. And, correct me if I'm wrong but to have 3D models in a game, you do not need a 3D engine? As it is just library of functions and managers. Or is it mandatory?
Thanx

[andrew.]

The functions and managers and stuff in the engine are what loads the models and textures and stuff. Loading models and stuff can be done in Turing, but you have to write your own engine to open and interpret the models.

[Insectoid]

You likely have to write your own 3D engine for Turing (someone made one recently over here...). You don't need have a special program to open these files, but if you want to open them, you definitely have to have something to draw the vertices to the screen where they are supposed to go, and handle all other information in the file.

EDIT: darn you andrew!

[CodeMonkey2000]

No you don't need an engine to load 3D models. Turing can open read these files with the simple command [b]open[b]. You will have to research how some of these file formats store information though. Iirc .obj and .ply are the easiest since they actually store their vertices in a readable text file. For example the points: (0,0,0),(1,0,0),(1,1,0) and (0,1,0) can define a 3D square. and it mabey stored in a text file as
0 0 0
1 0 0
1 1 0
0 1 0
All game engines do is read this data, and interpret and manage the data for you. If you aren't using someone else's engine, you can interpret this data yourself. Normally models are stored as a collection of vertices of triangles.

imo, there is no point in looking into game engines this early. Try to do everything yourself, you get a better understanding of what's going on that way, and making your own engine is more rewarding anyway

[isaiahk9]

Okay, let me go with an over-the-top scenario that will probably never happen :
Suppose that I made a model of a character in 3ds Max. Then, suppose I wanted to put that into a game I made in Visual Basic. Anybody if that's possible, and how you would do that. And how would a 3D model code look like for a complex detailed character model, if that is just a simple cube? finally, could I use some one else's engine that would work with VB? thanx

[Insectoid]

A complex character? Hundreds of lines of code.

[isaiahk9]

Oh well. Is there a Engine that would work with what I've specifified or not? As for making an Engine, how would the even be done in Visual Basic - it is an event-driven language.

[Zeroth]

3D engines are very complex. Even the most basic ones consist of a few parts. First, you need some way to manage textures. You need to be able to scale it, distort it, shrink it, rotate it quickly and easily. Then you need a vertex manager, which also contains info about which textures go on which faces. Based on the locations of the vertices, the engine scales, distorts, whatever the texture to fit in the right spot. Otherwise, it fills in the space with color information if it exists. The engine then needs to handle changes in the 3D environment, and for this, you need to have a decent background in physics, matrix math, etc. Most commercial engines handle most of this stuff very efficiently, offloading the main work of calculations and texture rendering to video cards. Thats just for a pre-planned scene though, with no physics, and no interaction. The physics and the application interaction is usually what is done by other companies.

Now, any file can be opened in Turing, VB, whatever. However, you will have to parse the format of the file yourself. Then you will need to do everything I talked about up there.

As a matter of perspective, Doom is all software-rendered. That is about the level of graphics you can get with software only. To get better graphics you need to interact with the video card, and thats the hardest part.

[isaiahk9]

OK, thanx everybody. 'Specially Zeroth. Found out everything I wanted to.