Car Modelling Overview and Tips
This is not exactly a step by step tutorial about polygon car modelling; it's more of an overview of the process I use and some tips that might help anyone having trouble modelling a car.
Although I work in 3dsmax, the process and techniques can be applied to all 3d applications, but this may not apply for one part about spline modelling, which is used only to make the basic polygon mesh, but you can just create the polygons, extrude them or do it any way you like. Well for a start, and I can't stress this enough, but if anyone is just starting out or wants to learn how to model a car then please use good blueprints! It's so important to use them, if you are still starting out and can't find blueprints for the car you like the most, check sites such as www.smcars.net
or just Google it to find the blueprints for the car you want, or order and download brochures from the official sites of the car company. Usually the blueprints come in a single image, It doesn't matter how you extract each view, whether it was in Photoshop or inside your 3d application it doesn't matter, it only matters that you have them in correct scale to each other in your 3d application. There are many tutorials which give good guidelines about using blueprints. Also it's very important to setup the blueprints properly and as accurately as possible, using reference objects to assist you, light corners for example, wheel badges etc...
I may have exaggerated the box reference objects slightly to give them funky colours, but it's only for the purpose of this tutorial. Feel free to do any reference objects in your 3d application as you like, this is only to make sure the blueprints are placed correctly.
Some of you may be a bit angry at me for not getting to the point yet, but seriously obtaining blueprints and putting them together accurately is such an important step that sometimes gets neglected, so I must stress this now. Now after you have the blueprints ready, you need to start modelling, at last. This is the only part where it's max related but, as I said before, you can simply create polygons or extrude edges or whatever you like to get a similar basic mesh, as you can see in the later image it's only used to get a mesh like that. Relax it's really no big deal to create a mesh like that in any 3d application, just follow the blueprints and think of a decent wire frame before you create the ploys and you will get it, really it's that simple! If you are having any trouble just look at any finished car wire frames and observe how the edge loops are usually done, it's easy to learn the tools and procedures but it might take time to practice that's all.
Now 'max users', don't be intimidated by spline modelling, it really takes nothing to learn. It could be just a little faster than standard techniques, all you need to do is to draw the splines following the blueprints exactly, in my opinion I think it's better to draw the curves in corner mode; just draw the curves as you see them in the image it really takes no effort, especially if your blueprints are properly placed.
I know the previous image looks cool but we really haven't started yet. One more thing to notice about these curves is that the points, or vertices, are aligned in an organised fashion, just check the image (you can also copy splines with the connect option, which will make the cross-section automatically please check your max manual and you will find it all. I don't want to make this tutorial too complicated).
Now spline modelling/ surface tools are really simple, just see the image, get the point, only a 4 or 3 sided, to create a surface (vertices or points don't need to be welded, just at the same position).
Now you have the main curves which resemble the car and they are accurate, just do the curves which will complete it and make it accept surface modifier to give you the mesh (you should make everything 4 or 3 sided otherwise it will make a hole. After you've made them, just add surface modifier and you will have a nice clean mesh with correct general edge loops.
Now the following is how to continue the basic mesh you've created, plus some general tips on things I have notice from that people who are just starting out. The first noticeable thing might be using too many edges, which aren't needed. Please don't add any edge loops unless you really need them and it's time for them, try to do the basic shape without all the extra edges because it will be easier to edit. If you make a small mistake and you want to change the look of a certain area in your model and you have too many edges, it will be next to impossible to fix the mesh. Re-doing the mesh entirely in many cases could be faster than editing a messed up mesh with too many edges.
Also, always check how your mesh looks after you add 'meshsmooth', it helps you realise what you are doing and if there are any mistakes.
Let's say you managed to get a nice clean mesh but it hasn't got much detail, only the basic form that we have created, it could be made easily by any 3d software even by creating each poly and it's very easy to do. Now some might leave their mesh like that and add meshsmooth to it, but it will scream "I am box modelled", and it will have no sharp edges, etc. The image below shows why you need to add edge loops to get the look you want.