Problem cutting parts for rigging

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Daxel
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Problem cutting parts for rigging

Post by Daxel » Fri Apr 26, 2019 5:27 pm

Hello!
I come from another animation software, and I'm used to cut some parts of a vector drawing for a variety or reasons.
Example: I draw an arm (one shape in one layer), and then I decide to split it in two (below/above elbow) to have each part in a different layer. With my old software I just used a cutter tool that cutted the fill and the lines and then I could copy and paste the parts where I needed them to be. I don't see the way to do that (to cut) in Moho Pro 12.
I don't find a good cutter. The eraser can do something similar but when you use it the shape gets deformed.
The other option I see is to copy and paste the points of one part of the arm, but I had many issues with that:
1) You can't cut exaclty where you want, because you are copying points so the cut has to be on a place with a point. This is not hard to solve, I just added a point there.
2) When you do this, you don't cut the fill, and it is just eliminated. Again, this is not ideal but you can fill it again.
3) To fill that shape again you have to close the shape with the "add points" tool, but when I do that the shape gets deformed and this is where I have a problem. While the other things may not have a solution right now, I think there should be a way to do this last thing. To explain this better I will simplify the situation: You draw a "U" adding points, and then you want to add a straight line closing the two ends of the "U". Can I do this without changing absolutely anything about the first "U" shape? When I do this the ends of the U change a little bit but I need them to stay exactly the same. I tried changing the curvature and I can get a very similar shape but that's a pain and it can be slightly different. I want to know if there is a tool to cut that I am missing, a script that can do the trick or if there is a way to do this with this tools.
Thank you for reading all that and sorry for my english. If I didn't explain myself properly, please ask me and I will try my best.
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slowtiger
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Re: Problem cutting parts for rigging

Post by slowtiger » Fri Apr 26, 2019 10:48 pm

Over here we do that differently: we already build the arm from several shapes which only appear as one.
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Daxel
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Re: Problem cutting parts for rigging

Post by Daxel » Sat Apr 27, 2019 11:14 am

slowtiger wrote:Over here we do that differently: we already build the arm from several shapes which only appear as one.
Thanks for answering. Yes I guess each software has different workflows but I find that a cutter that don't deform anything is very usefull in many situations. And if not a cutter, just being able to add a line to close that "U" I mentioned without deforming the original lines of the "U". I want to know if there is a tool to cut that I am missing, a script that can do the trick or if there is a way to do this with this tools.
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slowtiger
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Re: Problem cutting parts for rigging

Post by slowtiger » Sat Apr 27, 2019 11:44 am

Unfortunately in Moho cutting rarely works as intended, and I never had a satisfying experience with adding lines and welding points, so I totally avoid that. Also, a simple cut never is enough, as body parts on different layers need a certain amount of overlap, otherwise the character breaks during movement.

I recommend you get used to Moho's tools, do the tutorials, make some tests, because forcing a workflow from different software into this one will frustrate you in the long run.
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Greenlaw
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Re: Problem cutting parts for rigging

Post by Greenlaw » Sat Apr 27, 2019 2:54 pm

It takes a few steps: first select the path you wish to 'cut', enable Show Bezier and Fixed Bezier, then cut the shape using another path (or multiple paths) with Weld Crossing. Copy the path and wipe the path edges with the Delete Edge tool to remove unwanted segments, paste a copy and remove the other parts in the copy. Then, select the paths with the Create Shapes tool to stroke and fill the shapes. You can create the shapes individually or all at once for a 'single' shape.

Here's an example:

Image

Note that I left a few 'tails' in the path corners. These are necessary to hold the shapes and should be left in. Don't worry about them because they won't render if they're not stroked. If they really bother you, make them shorter before cutting or you can manually adjust the Bezier handles after removing them. (Not worth the trouble, IMO.) [Actually, there is a way to remove the 'tails' without affecting the shape. See the correction in the next post.]

It might seem like a lot of steps (it is) but it's not too bad once you know what you're doing.

That said, I agree with SlowTiger and tend to avoid working this way in Moho. Moho's curves are optimized for predictable deformation and interpolation, so it's better to use the original vector tools as designed. Once you switch to Bezier mode, the results can get pretty weird when you start deforming the shapes. This is just the nature of animating with bezier curves using bones and point animation.

My recommendation is to work with Moho's standard tools to get nicely deforming shapes, and switch use Bezier paths mainly for static or otherwise non-deforming shapes.

Alternatively, you can draw your elements in another program, save as SVG and import them to Moho. However, keep in mind that the same rules for predictably deforming/interpolating shapes still apply to imported shapes.

Hope this helps.
Last edited by Greenlaw on Sat Apr 27, 2019 3:51 pm, edited 2 times in total.
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Re: Problem cutting parts for rigging

Post by Greenlaw » Sat Apr 27, 2019 3:43 pm

Correction: Sorry, I forgot that it's possible to get rid of the 'tails' and preserve the shape by holding down CTRL and using Delete Edge in Delete Point mode.

Like this...

Image

I guess by killing only the end point with the tool, the angle at the remaining corner point is maintained.
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Daxel
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Re: Problem cutting parts for rigging

Post by Daxel » Sat Apr 27, 2019 11:40 pm

Greenlaw wrote:It takes a few steps: first select the path you wish to 'cut', enable Show Bezier and Fixed Bezier, then cut the shape using another path (or multiple paths) with Weld Crossing. Copy the path and wipe the path edges with the Delete Edge tool to remove unwanted segments, paste a copy and remove the other parts in the copy. Then, select the paths with the Create Shapes tool to stroke and fill the shapes. You can create the shapes individually or all at once for a 'single' shape.

Hope this helps.
Thank you so much! That was exactly what I was looking for and solves all my problems. And the difference between Delete Edge with and without Delete Point mode was very useful too. I'm glad I asked.
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Re: Problem cutting parts for rigging

Post by Greenlaw » Sun Apr 28, 2019 12:23 am

Glad that helped!

BTW, you can use the Freehand tool to draw the slices too.
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