How can I reduce the bumps on my strokes?

[Daxel]

Sometimes, when I'm tweaking the line width of certain points of a drawing to make it look better, I get like a small bump that doesn't look very smooth (see image atached). I'm not a native english speaker and when I say bump I mean a small non desired thickening of the line. The bump is usually just where there's a point with an intermediate line width value, for example: the point with the bump has a line width of 50, the previous point has 100 and the next point has 0 line width. It's usually hard to notice but there are some cases where it's more visible, specially zoomed in, and I wonder if there is something I can do to improve this, maybe some things to avoid, or some tips you guys learned working with Moho.

I see that sometimes it helps to reduce the points and try to not have points with intermediate line width, but I always avoid tweaking the beziers of the drawings I intend to animate, and that makes me need to put some more points to try to attain a certain shape without beziers, so sometimes I can't get rid of those points and I need a smooth narrowing like that crosses that point so I need the intermediate line width value there that creates the bump like on the image. I hope I explained myself.



https://1drv.ms/u/s!AiyKCw6Xey5TgZUAYR2 ... g?e=qdxTnV

[chucky]

Hi Daxel,
you seem to have a pretty good idea of what's going on
It is simply just a case of point position and thickness, to get control of that.
Yes, beziers can help but cause animation issues.

Maybe try not going all the way to 0 and or just playing with the shape till it works.

[Greenlaw]

Yeah, that's something Moho just does. I think it has to do with how it interpolates the smoothness of the curve as it passes through the points. I don't think you can completely get rid of the bumps, but you can probably minimize them with a few adjustments.

For example, I would try fattening up the point that's currently set to 50%, and moving it a little closer to the 100% point. Like so...



Tip: I personally avoid making the end point on a stroke 0%...I like to give the point a slight roundness as in the above example. I think this looks a little more 'natural' and less 'digital'. In your example, I see you need the next curve segment to be invisible, but instead of going 0%, try using the Hide Edge tool on that segment instead.

Bezier handles might also let you work with how far the width falls off from the point. I'm skeptical that this will be better, maybe just different. Also, Bezier points might not animate as you would expect. It's worth a try but be sure to save a copy of your project first.

An alternative approach is to draw the line as a filled shape, which will give you the exact shape you want, but this does complicate the shape for animation. I don't recommend this except for special cases (like, maybe for an extreme close up on the eye.)

Hope this helps.

[Daxel]

It is simply just a case of point position and thickness, to get control of that.

Maybe try not going all the way to 0 and or just playing with the shape till it works.

Thanks, that helps but sadly I can't completely get rid of the bumps, and sometimes I can't even minimize them without loosing points that are strategically placed for animation purposes.

I would try fattening up the point that's currently set to 50%, and moving it a little closer to the 100% point. Like so...

An alternative approach is to draw the line as a filled shape, which will give you the exact shape you want, but this does complicate the shape for animation. I don't recommend this except for special cases (like, maybe for an extreme close up on the eye.)

Thanks for the tips, moving it a little bit closer was possible in this case and helped a little bit, but still pretty noticeable lack of smoothness at close distance. I've seen people going the filled shape route: super nice result as I would love but yeah complicates the rig.

Yeah, that's something Moho just does. I think it has to do with how it interpolates the smoothness of curve as it passes through the points. I don't think you can completely get rid of the bumps.

I see. I would love to see this improved for the next version, more than anything. I know we are asking for everything at this point but, at least from my ignorance, it looks like something that could be easy to improve, and all the other programs I've tried managed to get working well. And at the same time, it's something important in my opinion. Not having full control of the thickness of our lines is something that I think could be a deal breaker for some artists.

[Greenlaw]

Yeah, it's almost like we need to be able to set interpolation modes for points, i.e., smooth, linear, step, etc. Right now, it's doing kind of a 'S' shaped smooth I think, and I think the middle 'flattening' part is the 'bump' you're seeing. Maybe we need a 'mode' we can switch to to avoid this 'flattening'. Or it just needs an improvement to whatever it's doing now.

I was about to ask for other drawing property improvements, like getting modes to draw inner and outer strokes, and not just center line. I can include this to the request.

In the meantime, I've been vector drawing in Moho long enough that I automatically plot my points to minimize and avoid the bumps without really thinking about it, and the bumps are really not that noticeable in my work. (I think.)

Having said that, this is probably going to get called out at work now.

[hayasidist]

this is an interesting one -- my guess, much aligned with Greenlaw's view, is that it's to do with how moho deals with the bends between points where the line width is changing. Even with "no brush" set, I think that means moho uses a default round solid brush and it changes the diameter of that, and the spacing between "stamps", to match the width of the line. The "bumps" (and troughs in some of my experiments) appear where the curvature of the line (even in between moho's points) is high - IOW, going round a corner, the "long edge" is very much longer than the "short edge" - and moho is placing "stamps" along the centre line...

I had a few attempts with different shaped brushes - small circles, thin sticks, etc - but none exhibited results that were any real improvement over the standard "no brush".

If all that is more or less right, then I'm not yet convinced this is a simple fix as it would mean changing from "dropping splodges along the centre line" (i.e. along the drawn path) to calculating the outer and inner boundaries and filling accordingly - e.g. looking at the orthogonals to the path at each "stamp point" and, if they intersect or are spread too wide for the standard circular stamp, working out how best to fill gaps / avoid excessive overlaps (maybe have a different "standard" stamp for such situations and deploy accordingly?!)

[Daxel]

I was about to ask for other drawing property improvements, like getting modes to draw inner and outer strokes, and not just center line. I can include this to the request.

Oh, that would be amazing, I also thought about that sometimes. Thanks for requesting it.

In the meantime, I've been vector drawing in Moho long enough that I automaticallyplot my points to minimize and avoid the bumps without really thinking about it, and the bumps are really that noticeable in my work. (I think.)

Yes it's usually hard to notice if you don't see the strokes too close, but sometimes you just want that stroke zoomed in, or you want a big stroke for one stroke legs, arms, strands of hair, etc that are very simple and easy to animate and fit certain styles.
And even when the stroke is not that big and you minimize the bumps, I think that you would find the drawing more clean without the bumps even if you can't actually see where they are. Kind of what happens when you apreciate a better quality TV even if you can't tell what's different.

[Greenlaw]

Oops...I meant the bumps are really not that noticeable in my work. (corrected in original post.) But, yeah, I'm sure it's there if I look for it.

[Daxel]

The "bumps" (and troughs in some of my experiments) appear where the curvature of the line (even in between moho's points) is high

I can get very big bumps with perfect lines, like on this image:
https://1drv.ms/u/s!AiyKCw6Xey5TgZUBdQVLQr5Kp-DaNw

But I don't have a clue, I just hope it is not too hard to solve. Maybe, if it's hard to get it automatically right in all scenarios, it would be nice if they could make some values accesible to the user to be able to tweak it like the interpolation method Greenlaw mentioned. And while we have that they could take their time to make an automatic solution for a future version, maybe v14.

Oops...I meant the bumps are really not that noticeable in my work. (corrected in original post.) But, yeah, I'm sure it's there if I look for it.

Yeah I understood it like you meant it for some reason.

[hayasidist]

The "bumps" (and troughs in some of my experiments) appear where the curvature of the line (even in between moho's points) is high

I can get very big bumps with perfect lines, like on this image:
https://1drv.ms/u/s!AiyKCw6Xey5TgZUBdQVLQr5Kp-DaNw

But I don't have a clue, I just hope it is not too hard to solve. Maybe, if it's hard to get it automatically right in all scenarios, it would be nice if they could make some values accesible to the user to be able to tweak it like the interpolation method Greenlaw mentioned. And while we have that they could take their time to make an automatic solution for a future version, maybe v14.

understood --- same basic problem - "wrong" brush / attributes for the length of the segment given the "large" difference in width at start and end - you can see it very clearly if you use a custom brush - placement of the "stamp" on the moho point - then step along the segment until the next point when the stamp size / position gets reset as appropriate for that point .. if you pick a custom brush then tweak the "brush spacing" attribute it should be clear what's going on. Totally agree it needs a fix - it's just I don't think it's "trivial" (would love to be proved wrong though!!)

[this, BTW, has been a source of annoyance for me for ages when using custom brushes and the curve length changes - the number of stamps along the line changes ...]

[Greenlaw]

Thinking about this some more and I guess another problem is that the in-between point needs to be able to adjust its width automatically as you move it. ATM, the in-between point maintains its fixed size when you move it closer to either of the next points, so you lose the grade you want unless you also animate the point's width too. Too much trouble deal with, IMO.

I was looking at some of my old work where I have tapering points at the ends of lines, specifically the Boss Baby stuff which was all Moho vector art. It looks like I just avoided inserting an in-between point at the ends at all, and the rest of the points are mostly fix width. (You can see what I mean just by looking at the thumbnail art.)

[Greenlaw]

Speaking of Boss Baby, I was noticing how I drew Timmy's eyes with a break in the line like you're doing. I'm pretty sure I just used Hide Edge here instead of adjusting the width to 0%. I think this is easier and the results are cleaner.

[Daxel]

Speaking of Boss Baby, I was noticing how I drew Timmy's eyes with a break in the line like you're doing. I'm pretty sure I just used Hide Edge here instead of adjusting the width to 0%. I think this is easier and the results are cleaner.

I thought about it, but my eye was way smaller so I was looking for a smaller break, and at the same time to make a small break using hide edge I would have needed to add aditional points that I didn't want there. But it's still a work in progress so I'll probably try more things, I usually rebel against my original design at the rigging phase.