Hi Kevin, yes I still don't recommend that you use this process in place of your existing one, like I mentioned previously the level of adjustment and detail that you want to achieve would not be any easier and most likely more time consuming with this method rather than your current one.

This does not change any of that.

However, I wanted to show you what the suggested approach would be if you (or someone else) did want to build this using NURBS. You were previously saying it was not possible to build such things with NURBS because of bunching and warping issues. I wanted to show that there is a method that can be used that does not create warping and twisting, but you do have to use a different strategy than your original one.

I mean you can clearly see that the overall form that I created there does not suffer from bunching or warping issues.


> With the canopy surface you've generated I could not cut the
> windshield to the right shape.

Yes - please understand that I did not take a whole lot of time to do that shape, if it is not the correct shape you would need to edit the curves and tweak things. That is not a whole lot different than your polygon modeling approach - doing things in polygons does not automatically create them at the perfect shape immediately, you have to do a lot of tweaking to manipulate the shapes. The same principle applies here as well.

So even though you could not generate the windshield to the right shape with the specific canopy I have created here, I hope you do not think that it is not possible to create a suitable shape with further edits, because that is certainly not the case. I wish I had time to demonstrate and prove to you that it is possible to create every single one of these little details to a very exact specification, but I'm sorry I just do not have the time available to do that.

I would probably have to spend quite a bit more time studying a lot of details of the shape to become more familiar with it before I could try to create something to meet the level of detail that you are targeting.


You're certainly right that it is a challenging shape to work on!


> The only problem is that a user can't point pull after a surface
> is trimmed so he can't tweak the shape till it looks right
> compared to photo reference.

No, that's not quite accurate - you can still turn on points and manipulate them on a trimmed surface, but not on a joined assembly of surfaces, you have to use Edit/Separate on a joined together cluster of surfaces to break them into individual pieces and then they can be point edited.

But there is a general problem of after trimming if you yank things around you can pull trim edges apart from one another.

Again though the general strategy is to form the shape of each component more correctly and fully before you do any trimming. You would not want to trim and combine them until you liked their shapes.


> Nor can the user define how many points should be put on
> the surface to aid them in the point pulling exercise.

That's not quite accurate either, for example if you use Rail revolve that will create an output surface that has the exact same control point structure as the input profile and rail curves combined, so you can insert points as you want on the input curves to control the point structure of the final result.


> As we have discussed point pulling is probably best handled
> with a subd poly modeller which is designed for that purpose.

I agree - definitely it is a focus of that toolset and once again if that is your main focus for how you want to operate then I would recommend going with that toolset instead.

Again, my last post was not an attempt to convince you to use NURBS instead of your current workflow, but rather as an explanation on how one would go about this task if you did want to use NURBS for it.


> I don't want to build the model panel by panel (even if a could)

The reason why I mentioned panel by panel, is your previous post here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2036.31
showed that you were using a panel-by-panel type approach when you were trying to build this in MoI, and you were complaining about buckling and seams between pieces. That strategy is not going to be fruitful with NURBS, you have to use a different strategy of making components that intersect like I was showing in my last post. It is a totally different way to approach the construction than the way you were doing it...


Again, sorry if my last post was not clear, it was not meant to convince you to abandon your current method of working in polygons, but just to show you what type of an an approach you would need to adopt to construct such a thing with NURBS without the kind of buckling, warping, creasing problems that you had encountered.

It is not an easy method, it kind of requires use of many of the detailed and advanced parts of the NURBS modeling toolset. It may require you to do things like subtle edits and visualizations of how pieces intersect before you get a good result. I do not really think it would save you time in your particular case of needing such very minute details and tweaking, but for other people's purposes who are not so particular about replicating very minute details it could be useful and just generally shows off the approach that you would use for creating more seamless skin type models using NURBS.

- Michael