Hi Michael,

First off - excellent work on Moi3D. Real easy to use and a lot of fun too.

However, (unfortunately for me), I cannot seem to get rid of some seams on a computer mouse that I modelled this past week. I know it is from edges not being welded, but these have been joined before export, and the export box requesting welding of edges was ticked at the time.

I have read a similar post regarding this (related to Poser). I'm just a bit confused about the weld problem having ticked the weld box.

Would love to hear if there is a way around this.

Thank you,

Steve.

Hi Steve, it looks to me like the 2 halves of the mouse are not matching up smoothly in the original model in MoI, that will also create those kinds of sharp edges.

Could you also please post the .3dm model file as well? That will help me take a closer look at it and make it easier for me to offer suggestions.

- Michael

Thank you for your reply Michael.

Attached is the file. I used scans of my mouse to generate the curves (Microsoft optical mouse).

Thank you.

Steve.

Hi Steve - yes definitely those pieces are not touching each other smoothly, they are coming together at a crease.

When you do the polygon export, switch the display: option to Display:Shaded, and you can see the crease a little easier there when lines are not being displayed along the edges.

This is just like the sharp edges where faces of a box come together - just welding won't normally change this.

To get this to be a smoother object, I'd generally recommend trying to build the upper part that is supposed to be smooth all in one single surfacing command, like all one sweep. That tends to make it easier to get a smooth model there, it is difficult to make thing smooth when building in little pieces.

The other problem is some of the pieces are not quite exactly aligned with one another, the halves seem to be overlapping a bit (which is hard to see unless you zoom in a bit), instead of touching exactly. That makes it hard to join the pieces together also.

I'll see if I can come up with an example of a different approach.

- Michael

Hi Michael,

Thanks for your ideas. I had started the mouse with one large area (just the outer limits of the curvature) but couldn't seem to find a way to make the curve except 'network' which seemed to need some curving framework.

I rebuilt the mouse a few times (particularly after I found a crack down the middle after using mirror - must have had a point move after splitting to avoid re-networking the same areas a second time).

So do you think I should experiment more with loft?

Your help is very much appreciated.

Steve.

Hi Steve, well here is an idea for a much different approach.

I took your curves and moved them to center around the origin, it is kind of a good idea to use the origin snap to make sure things mirror and align exacty.

Then I took the curves for the top curvy piece, and drew some little extensions on them, so they kind of extended further. I also used Transform / Scale / Scale1d to kind of stretch things out slightly. I did this to get this kind of setup:



So the idea here is to create a much more regularly shaped outline for creating the top surface. It can be difficult to construct a smooth surface directly off of curves where one curve is kind of bending and contorting quite a lot more than the other - the surface construction commands will tend to create bunched-up type surfaces in that kind of situation.

By building a kind of extended curve frame you can make the curves a lot more similar in shape, this will tend to make smoother more controlled surfaces.

So after extending those curves, I used Construct / Network to build a surface there:



Then I took the bottom outline which is all one closed loop, and extruded it upwards:



Now select that big block piece, and use Construct / Boolean / Difference and pick the curvy network surface as the cutting object. This will slice the block into 2 pieces, discard the top piece and you're left with your mouse shape:



This one is not quite perfect, it still needs some tuning in the network surface to smooth out some of the curves so the network is not quite so wiggly. Less wiggles will make for a cleaner edge curve where the 2 pieces intersect.

So you can see the general idea here is to not try and follow quite so exactly along every single digitized contour of the final 3D mouse. Sometimes it is much more controllable to extend your curve framework so that it can be more simple and regularly shaped, and then use booleans or trimming to cut things back to a more wavy edge.

With this method, you kind of give up the exact control of the edge where the 2 pieces meet, instead of drawing that directly it is the result of the intersection between surfaces. But because you deal with a more regular network your surface quality will be greatly increased...

Model is attached here as mouse2.zip

- Michael

Hi Michael,

Thanks for all the help with the mouse. Unfortunately, there are very few tutorials on the net about mouse creation so a lot of what I did was guess work.
Really interesting to see your 'smoother' approach to the problem, and an insight into how I can model with moi in a more effective way.

Many thanks,

Steve : )

You're welcome Steve.

It's not exactly an immediately intuitive way, because you kind of have to imagine the surfaces extending further than the actual end model result.

But generally the surfacing commands will be much more controllable with input curves that don't change shape quite so much between them. In this case especially the area towards the front will be particularly difficult to create with good quality since the lower edge makes a pretty sharp swoop and then comes right in to touch at a point...

But when that swoop becomes a trim curve with a larger underlying surface, it makes the surface able to be far more regular and not so squeezed or stretched.

Sometimes it is hard to recognize at first when an edge would be better as a trimmed back area. If there was a little circular hole in the middle of it, it would be a lot easier to recognize immediately that you shouldn't try to use the edge of the hole for creating the surface (like trying to sweep or network off of the hole's edge directly). When it is on the outside edge of a shape, it doesn't quite pop out as much as being more naturally represented as a trim curve, but sometimes it is...


It might be possible in this case to just do the extension in the very front part only, just right in the area where it bends inward - trim there and extend out so there is a sharp corner just in that spot instead of a bend, then trim back after that.

- Michael