Hi Michael,

Just a slight problem I have encountered. I went through a similar route as you, using a Loft to create the helmet and all seemed fine until I went to export the mesh. The preview shows the topology as crooked.

The attached pictures should show you what I mean.

Thanks.

Hi Beowulf - that looks like a side effect from doing the loft using full closed loops instead of half curves like I was using.

When you loft between closed loops, MoI needs to find an alignment point between each section, so that there isn't any twisting between sections.

MoI does some calculations to reduce twisting, but if you want a particular exact alignment you may need to adjust it manually.

When you do a Loft using closed sections, you should see a display that looks like this (while you are in the Loft command, before you push "Done" to finish it):



Those points that are displayed are the alignment points between each section - switch to the top view:



Then click and drag on those points to line them up some precise reference line, like the world y axis line:



I think that will tune up the topology to be what you want.

If you still have difficulty with this part, please post your curves as a .3dm attachment here (or e-mail to me at moi@moi3d.com) so I can check out what is happening.


When you loft between open curves there isn't this same issue because it is very clear to MoI how to connect 2 open curves together, just by aligning an endpoint to another endpoint.

- Michael

Does the edge direction of the polygons have any bearing on the end smoothness? If your file had been saved to tris I think it would have looked just as 'poly-twisted" but also not have any effect on end results. I regularly see this sort of thing but have never taken any notice of it as a potential problem?

I look forward to a properly informed reply.

Hi Brian, it doesn't particularly have any effect on regular rendering.

But if you wanted to use polygon modeling tools to do some further editing of the model in the polygon environment, then of course it is nice to have the polygons as well organized and structured as possible.

There are also some other cases where it can make a difference, like you may want to do some special rendering effects where you actually display the wireframe to get a kind of technical design look.

- Michael

Thanks Michael.
It follows, for how I generally work, that I dont really need to add this extra "worry detail" to my methods.

Obviosly I am trying this Helm idea as well.
When I try to boolean the holes in the helm I also get a set of holes at the back--seems very odd?

I guess I worked it out. You have to start with an extrudedobject before starting the array!
Anyway, quite happy with the quick exercise as per the jpeg. More learning into the basket.

And some rendering fun with Carrara5Pro.

Hi Brian,

> When I try to boolean the holes in the helm I also get a
> set of holes at the back--seems very odd?

It looks like you figured it out already, but just in case - what seems to have happened here is you arrayed not only your cylinder, but the original circle curve that created the cylinder as well.

Then probably those circle curves got selected as cutting objects in addition to the cylinders.

When you use a curve as a cutting object in a boolean operation, it will slice all the way through the object, it won't only cut just the front side of it.

Nice flag at the top, you are really getting the hang of things!

- Michael