Thanks, but if you keep the curve used for your construction you can modify the resulting shape isn't it?

An other thing, I can't find a way to make a rail revolve using two rail curve, is it possible?

<< An other thing, I can't find a way to make a rail revolve using two rail curve, is it possible?
No for the moment! :)

Ok thanks ;)

Hi Dmarmor,

> Thanks, but if you keep the curve used for your construction you can modify
> the resulting shape isn't it?

Yup, that's the history feature where after you've created a surface you can edit the curves that went into it and it will recalculate as long as you haven't done some other type of edits on the surface.


> An other thing, I can't find a way to make a rail revolve using two rail curve, is it possible?

Not in rail revolve, but you can do a Sweep with 2 rail curves.

- Michael

Hi, still learning MOI and I have a couple of questions for you ;)

I'm still on the same subject and try to grasp the concept.

I have a little issue when building my surface that I can't resolve, there is a little bulge visible.
How can you avoid this? you can see it on the bottom front panel.
I rebuild my curves but it is still there.







Thanks

Hi Dmarmor, could you please post the 3DM model file ? That would help me to take a more in depth look at your actual geometry, it can be easier to answer questions when I'm able to look at your actual objects rather than only a screenshot.

It's hard to say from just a screenshot, but it's possible that what you are worried about is a display artifact and not really an intrinsic part of the real surface. In order to display a surface on screen it has to be broken down into triangles, and in a curved area if there were not a lot of triangles created it can leave a bit of evidence of the triangulation in the on screen display.

One way to see if that is the case is to do a test export of your model to a polygon format like OBJ format, and then crank up the density there and set the display mode to be shaded and that will show you a lot more detail on the actual surface form and minimize display artifacts. That's the kind of thing that I would do over here if I was able to examine your model file.

- Michael

Unfortunatly I'm using the trial with no save so I can't save this file.

And I finally I solved my issue, the bulge was visible because of bad curve construction.

If I can add a question, is it possible to have a jiggle parameters for the array to add some imperfection in the placement of the objects?

And an other thing I didn't find, how do you project your curve on one side only? Currently it project through the whole object and you end up with two curve, the same things happen with the boolean diff, the hole is occuring through the entire object and I would like to have a control on the depth of the cut.
Thanks

<< If I can add a question, is it possible to have a jiggle parameters for the array to add some imperfection in the placement of the objects?

You can use some random selection of something ;)

Take a look here at this thread ;)
http://moi3d.com/forum/index.php?webtag=MOI&msg=3974.1


And for jiggle look at this one
http://moi3d.com/forum/index.php?webtag=MOI&msg=6447.1

Hi David,

> If I can add a question, is it possible to have a jiggle parameters for the array to add
> some imperfection in the placement of the objects?

There isn't currently any mechanism for doing this - it's usually not very feasible to get good results by just randomly jiggling control points around, especially if the control points are not completely evenly spaced it's easy for some of the points to have a more pronounced impact on the end result.

MoI is overall itself not focused on generating organic type shapes, usually you would want to bring your model into a different program that is focused on that type of thing to add those kinds of details, like import it into 3D Coat or ZBrush.



> And an other thing I didn't find, how do you project your curve on one side only?

You would usually just generate the projection on both sides and delete the one that you don't want. Also if you're trying to project for the reason of cutting a hole in an object using Trim, Trim has projection built into it so it's usually better to not do the projection as a separate step. When you pick which areas to discard in trim it will only use the projections surrounding those pieces.



> the same things happen with the boolean diff, the hole is occuring through the entire
> object and I would like to have a control on the depth of the cut.

For controlling the depth of a boolean, do an extrusion of your object to your desired depth and then use the extrusion as the cutting object instead of the curve as the cutting object. In the future I do want to add a "limit depth" option to the booleans that would handle this easier, but for now you just construct an extruded cutting object.

- Michael

Thanks for the answers.
About the jiggle I think it is a very specific demand and it was not about the placement of points but of curves or objects.
The great helmets have holes in front, but these holes are not made by a machines but by hands.
So what I wanted to do is to make an array of circles along curves to place the cutting objects, but I didn't want them to be at the exact same spacing.
I wanted to introduce some small differences in the spacing, not really noticeable but still present. That help to make it hand made.
But in most case I will use MOI to make "industrial" objects so that is a really specific case. I just don't have to build my medieval armours in MOI :D

About the scripts I'm not sure it will work in my case, but I found some interesting scripts along the way.

Hi David - jiggling entire objects a bit is a lot more feasible than trying to jiggle curve control points. Check out here for a randomize plug-in which you can set up which will let you do some random movement, scaling or rotation on objects, it should work to add so me non-uniformity to your cutting holes:

http://moi3d.com/forum/index.php?webtag=MOI&msg=5416.5

- Michael

Thanks Michael,

The script will do the job, an other usefull tool to use.

Still learning Moi, and still liking it, not that it goes along smoothly everytime but some headaches I could have with polymodeling are so simple here.
But I have to admit that sometimes its simplicity make things difficult, you have to make many action to get a simple result.
For example I had an hard time to cut a surface from a projected curve, I was not able to do it so I had to make a shape from the original curve and use it for a boolean diff.
But I will use this method more often as it seems to be the way to go. The downside is that it need a lot of planning and doesn't allow for a streamlined creation.
Many time I had to redo my shape because I made a mistake while constructing my shapes.

This for example, I build the flat shape from a curve but build only one half. I then made an offset shell to get my thickness but the result was not correct at the middle after doing a mirror.
There is a way to fix that or do I have to rebuild my curves? What I had in mid was to take the border edges and align them at the center and then merge the resulting shape. It's possible to do that?


Sometimes when I have finished my shape and I need to make a forgotten operation I'd like to retrieve the curves from my shape, is it possible?
I'd like to have just the exterior line to be converted as curves, but I didn't find a way to do so.

An other thing about this helmet is that I wanted to have each panel overlapping each others, like the real object. I suppose I have to do it with my curves or I can do it when my solid are built?


Here is the short lived result as I'm using the saveless version ;)
Not really happy with it but that's just an exercise and I learned a lot. That's a really simple object but it was a hard time.





One last question, is it possible to keep the object used to create a boolean and edit them while still seeing the change in the resulting boolean?
Something like meshfusion, you have a plane cutted by a cylinder and if you scale your cylinder you see the resulting boolean changing, same for any kind of boolean operation?

Hi David,

> For example I had an hard time to cut a surface from a projected curve, I was not able to
> do it so I had to make a shape from the original curve and use it for a boolean diff.

If the curve became non-planar after it was projected, that would cause that type of effect - boolean difference can only directly use 2D planar curves as cutting objects, they become extruded as a process inside the boolean.

If you want to only cut some limited distance into an object instead of all the way through then that is normal that you would build a shape from the original curve and use it for the boolean, that's the process for doing that...



> Many time I had to redo my shape because I made a mistake while
> constructing my shapes.

As you gain more experience these types of mistakes will become less common.



> This for example, I build the flat shape from a curve but build only one half. I then made an offset shell
> to get my thickness but the result was not correct at the middle after doing a mirror.

Yeah, that's just how offset geometry works - the offset surfaces generated from individual surfaces will only touch each other if the surfaces are smooth where they meet up.



> There is a way to fix that or do I have to rebuild my curves?

You can try to join the surfaces together before you do the offset - that will then make the offset surface get extended to fill in the missing area.



> Sometimes when I have finished my shape and I need to make a forgotten operation I'd like to
> retrieve the curves from my shape, is it possible? I'd like to have just the exterior line to be converted
> as curves, but I didn't find a way to do so.

You can extract edges by selecting them and using Copy/Paste to duplicate them, the pasted result will be separate curve objects.



> An other thing about this helmet is that I wanted to have each panel overlapping each
> others, like the real object. I suppose I have to do it with my curves or I can do it
> when my solid are built?

You can move the panels around after you have created them. But if the overlapping involves some kind of shape adjustment rather than just movement alone then you would want to have that set up with your curve structure instead.



> Here is the short lived result as I'm using the saveless version ;)

It turned out well!



> One last question, is it possible to keep the object used to create a boolean and
> edit them while still seeing the change in the resulting boolean?

No, not currently but that is something I want to add in the future with a deeper history mechanism.


- Michael

Hi Michael
This time I have an issue while trying to build a shape using the sweep function.
I tried to follow this thread to build my shape but I can't get the same result.

Here is my curves, following the same color code from the thread, and the result I have.









The resulting file is attached too, do you know what I did wrong?
Thanks

Check out blue and black non-intersection?

Why do you make Sweep ?
It's typical something for a Network!

I checked my intersection, I recreated the curves but there is always the same issue at the same spot. I was not able to track what is causing it.

I made a network but I had a pinching. I'll try to redo it.

Thanks for the support.


Edit: I tried to make the shape using network but it doesn't work. I get a funky shape, I have no clue what I am doing wrong.

I moved the two end points of the right hoop to intersect, and network seemed to work very well.

I have to reload my last file as I did several change.
Here is how I cut my curves, maybe I am overdoing it.
But with these curves I cannot have a proper shape from network.





Ok I was able to make the network correctly but I have pinching at the end of the shape. That's why I wanted to use Pilou technique with the sweep.

Here is what I have at the end.

Hi David, re: sweep problem,

> The resulting file is attached too, do you know what I did wrong?

It looks like the same problem from this other recent thread here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=6605.5

When you use a scaling rail the scaling rail must cover the entire extent above the rails - just making it touch the profile is not necessarily far enough if your profile is not planar and directly above the rails.

Sometimes it can be easier to construct things like this with more planar pieces like flat rails and then introduce warping later on using the Transform > Deform > Flow command (which is new for the upcoming v3 version), rather than using a lot of 3D warped rail curves from the start.

But anyway your particular sweep here can be fixed by extending the scaling rail in the side view so that it covers the entire area perpendicular above the rails like this:



And you're probably best off making the proflie for the sweep to be positioned perpendicular to the rails rather than having it start out in a slanted position, if you then want to introduce a slant at the end when you're done with the sweep use a boolean or trim to cut off the end with a line rather than trying to build a surface with slanted pieces right in the initial surface construction.

I've attached an example 3DM file here which should work better. Also I aligned the end point and first inside control points on the rails so that the curves are smooth where they touch rather than coming to a sharp angle where they connect.

- Michael