3D understanding newer

unit 66/67/68
Charles Hardy

3D Modelling

There are many different types of modelling and techniques used to create the world you see around you in games. I will be explaining some of these techniques and how they work below:

Working to the brief and ideas generation

If you are tasked with making a game like assassins creed origins, you would be told to make models like old Egyptian weapons etc. You can't then make a m4 machine gun because that would not be correct to the game you are making. You have to work to the brief given but you can make your own ideas. Your own ideas can consist of different weapons and items to maybe altering the landscape slightly to make it look more stunning etc.    

Box Modelling

Box modelling is a type of modelling that is used where the model starts as a basic shape and then using the sculpt tool you can create different shapes and then finally creating the image you want. An example of this being used would be in you wanted to have a head shape you could slowly cut off corners until you get a shape that looks like the latter heads in the image to the right. It is a useful method to create a basic rough outline and it could almost be considered a sketch.                             

Extrusion Modelling

Extrusion modelling is a type of modelling where you take an image an essentially draw with 3D modelling around it. It is like sketching with 3D modelling, it is an efficient method but requires a photo or drawing. This image shows someone modelling a face using the method.

Other types of modelling

You can also just use the basic shapes to create something, for example you could just use cubes and rectangles to create a house etc. The whole point of these simple shapes is to allow someone to have an easier time to create a more simple model or have a better place to start. You can also cut shapes and make then more easier to work with what ever shape you need. For example you would use a cone if you wanted to make a traffic cone etc. There are many different types of basic shape that you can use, they are all useful for something. 

Constraints

Constraints are an important thing to be aware of because if not taken into consideration then you may be left with a lot of difficulties later on down the line in development. File size is one of the most important constraints that any game developer will have to overcome, if your game is so massive that you would need 100's of GB to download it. No one is going to download it, mainly because some gamers would not have a hard drive that big to store the game and those who do would not want to have a game of that size on their hard drives. Another problem with this is it would take a lot longer for textures etc. to compile. This is extremely bad because of the long time wait that takes place when compiling just a few GBS but if the textures etc. were 10 or 15 GB then it would take many hours which would be wasted doing nothing as compiling takes up a lot of PC power, saves would also take a long time and if there is an auto save every 5 minuets then the pc would lag a lot of the time. An example of this is a game called "rainbow six siege" where the developers had to pull maps out of the game because they where running out of storage. This is one of the backlashes that not handling your storage to an adequate degree. Rendering time is important in the game as you do not want your player looking around and seeing the world rendering in as it would look unrealistic and very sloppy which you don't want people to associate your game with. It's important that you find a good balance between good graphics and fast smooth rendering, with of course causes games like the last of us to look and render so well because naughty dog found a good balance. 

3D programs   

There are many different 3D programs that you can use to create your 3D image. Maya and Blender are personally the ones I have used the most which means I will mainly be focusing on them and the differences between each of the programs. First off Blender is much more complex when you first look at it which makes Maya much more user friendly. Maya and Blender also use different file types but also the same. Blender uses a lot more file types but both use OBJ. files as their main files. An OBJ file is simply a "object" file which (if you are 3D modelling reefers to the object you created) but blender also has other file types such as "STL" or "X3D". Blender definitely focuses more on the actual making of the models rather than other things while Maya you can animate. You can also animate in Blender but personally I have found that Maya is a better choice. Plug ins are also a part of every development program and can be used very well and easily. A plug in is simply a add on to the program that does not come with the original product. For example add block is a plug in for Google chrome, in blender asset sketcher is a plug in that you can use to sketch images (extrusion modelling) or for Maya you can use Maya carbon scatter to make environments easier to make. 

Applications of 3D

3D modelling is not just used in games design and it is actually quite important for many different other jobs. You can use it in the following jobs: product design, animations, TV, film, web, education, architectural walk-through. In TV shows and film it is used very similar to how you would use it in games design as cut scenes are almost like a mini animated movie but product design etc are very different. Product design is different because you do not want to design your product the same way you would design a cut scene. You want to design it in a way so that people see your product. 3D modelling is also used in architectural design, for example if you wanted to model a house you can model it in a 3D modelling program and then once you built it in the software you will have a better understanding how something needs to be made. Finally we have education which is partly what we are using it as right now, we are using it to learn how to model things for games design. 

Geometric theory

Geometric theory (aka polygonal modelling) is basically a much more complex version of "connect the dots" you draw things by using corners and polygons. A polygon is made up from using small triangles which are made up from vertices, edges and faces. The triangles are made from 3 vertices (green) 3 edges (black) and one face (red), this is obvious but geometric theory is not just triangles (it can be other shapes i.e squares) but triangles are the most simple and easiest to use. The way rendering works is if something is covered up by something it will not render. An example is the following image, the mountain (while obviously existing) it not rendering for the player, it simply is not there. This is the way it is because computers will need to save memory as the game is very large and needs to save as much memory as possible so that the game is "well optimized" and so lower end PCs can run the game.