CHAPTER 02: MAX and NURMS

NURMS in Practice

First of all, the way the panels are made. Generally starting on the edges, initially, I started with a cube like so, with three faces on the rear side removed.

2d: The effect of meshsmooth (NURMS) and the basis for the first part of our model. The bottom image has the "show end result" checked on, we can see the original mesh (orange) and the smoothed mesh (green) on top of each other

You can instantly see the effect NURMS has on the mesh by applying a meshsmooth modifier and clicking the "show end result" icon under the modifier stack. Generally, You will be modifying the mesh under the meshsmooth, and checking the results, when you get used to the way NURMS react with the mesh, you will be able to model whole panels, and only check the result of the NURMS at the end.

2e: Do all the editing of the mesh with the bottom of the stack, and check the show end result button to see what your changes are doing on the fly

As for interations, you should never really need more than 2 interations, and only at render time, it would be stilly to work in the view port at such detail, so check the "iterations at render time" checkbox, and start at one or two. By the end of the model you should be proficient enough to not need to see the iterations in the view port and will be amble to rely on your knowledge of the meshsmooth modifier enough to know what the end result will be.

2f: You rarely will need more than 2 iterations, and never in the view port, generally I used 0 or 1 in the view port, and 2 or 3 in the render iterations.

Place the box or piece of geometry somewhere on the vehicle spline, this will be our starting point for the whole model, eventually the entire car will be created from this one box.

2f1: Find a starting point for your mesh, the detail may seem overkill, but use discretion as to where you need the detail and where you don't.

By selecting the edges that will continue along the spline model we made earlier, we can create the geometry off the edges by pressing shift, then dragging like so:

2g: Rotate the view regularly to make sure your mesh is following the spline guide correctly

And continue on like so:

2h: You can create a very large amount of mesh in a short time by shift dragging

You can deal with creases the same way you deal with the rolled edges, just create more geometry where the crease is, remembering that we need to keep everything 4 sided, this may involve turning, and hiding / showing invisible edges. NURMS only sees visible edges, so it DOES matter if an edge is visible or not, NURMS will ignore invisible edges.

2i: Keep the detail where you need it and make sure every face is 4 sided

You can see an example of this by showing end result and hiding and un hiding an edge.

2j: The top image is the original box without mesh smooth added, the middle image is the same box (shown in orange here) with meshsmooth added. The final image is the result of hiding the edge selected on the original mesh in the top image, the results are messy and hard to predict

Now shift drag the larger surfaces of the bonnet to create the larger areas

2k: shift dragged edges

Vertex snap all the vertices together and weld them (Ctrl-W by default). You have to make sure all the vertices that touch are welded, not just snapped on top of each other, as the results will be dodgy and the mesh smooth wont work correctly. When you finish an area, you can select all the vertices and weld them all, if there are any left un welded, it won't come up with the dialogue box "No vertices within welding threshold".

2l: After some serious editing, its good to select all the effected vertices and weld. Be cautious of unwanted welding, your detail should be so that they are just on the edge of the threshold much of the time.

Careful particularly on the edges of the panels where the vertices are close together, that the vertices don't weld, they may do so without your knowledge if they are close enough, so be sure to check that they haven't.

2m: This happens a lot, two vertices are JUST within the threshold and create this sort of issue, undo and move them slightly further apart is possible. If you are constantly having this issue on the default threshold setting, perhaps your model is a bit too detailed..

After creating a surface, rotate the object around and watch the specularity on the surface, look for bumps and irregularity's, you will find that time spent tweaking and adjusting each and every vertex will far out way the amount of time you spent originally modeling the surface.

When you move onto createing the next panel, use the faces on the edge of the previous panel, duplicate them, move them away, flip the normals and then snap them back to the first panel as a seperate object, then continue on from there, this way you will get no gaps, and technically, none of the panels will "overlap"

Also keep the names of your objects obvious, a car has many many parts, and can get confusing, you could use "BODY" as a prefix to all the panels elements, then the part and location like so, "BODY - Door Right" and "BODY - Air Dam Right"