Antialiasing issue. Going crazy. Please help me!!!

[keepfungus]

Hi everyone,
Please help me, I'm going crazy with this antialiasing problem!
Can someone explain to me why the edges of my rendered strokes are smooth only if no brush has been applied to the line?
As soon as I apply a different brush, whether from the default library or a custom brush, the rendered edges become terribly jagged.
In the viewport, they look perfect. The renderings, however, suck!
In the project settings, the "Antialiasing" property is checked.
The renderings start to look smoother only if I get really close with the camera.
What am I doing wrong?
Please help me. I use Moho daily for work, but I just can't go out with renderings like this.

Thanks

Matteo

[slowtiger]

It helps if you could post some example image. Also information about project dimensions and line width. This sounds strange, I've never had problems like that.

[Greenlaw]

I've seen this problem with 'aliased' brush edges going back many, many years. I think it has something to do with how Moho interprets the alpha channel and how it stacks the sprites.

A while back, I conducted a bunch of tests comparing renders using grayscale brush images and grayscale brush images with an alpha channel, and there were noticeable differences. The results were inconclusive, but you can find them in this forum. My guess at the time: it's not that the brushes have no anti-aliasing, rather they're rendering with higher-contrast edges than normal, which can look like there's no anti-aliasing in the final render. Regardless, they shouldn't be doing that. (When I have time, I'll see if I bookmarked that topic...I'm pretty sure I did.)

Anyway, what I've found is that when using Moho's native brushes, some render with a harder (i.e., aliased) edge more than others, so I try to stick to the ones that look visibly smoother.

When making my own custom brushes, I try to tweak the alpha to minimize the problem. I don't think this is an ideal solution, though, because the brushes will probably need to be recreated whenever LM fixes this problem.

I haven't thought about this issue for a while; I should revisit it and run some new tests.

[synthsin75]

It would help if we knew the name of the brush, line width, etc..

[Greenlaw]

I...When I have time, I'll see if I bookmarked that topic...I'm pretty sure I did.

Oops! I found the bookmark, but my tests and notes are from a past beta cycle, and I can't share the link. However, I think I have some brush tips that may help with the AA issue. Let me run through my notes tonight and see what I can share.

[heyvern]

I once set antialiasing off in the export animation window. This is a crazy long shot, but I did it ONCE while experimenting. It would affect the entire render, not just brushes.
Also, not sure it would affect brush images, but there is a setting in the export for "extra-smooth images"

Another thing might be something to check: are you rendering to mp4/mov or image sequences? Not likely but might have an effect. It also depends on alpha rendering. Sometimes the software I use for compositing gets "wonky" with the alphas. You might need to experiment with premultiply alphas.

Just off the wall crazy things to check.

[Greenlaw]

Good call! Extra Smooth renders the image double-size internally, and then scales it down to the target size before saving it. The result is improved AA quality at the expense of nearly 4X render time. Since it affects the entire image, it should improve the brush edges. I think Extra Smooth only works during final render output, not preview render (Ctrl-R), so make sure to compare the quality with the result from Moho Exporter or Export Animation.

IMO, the higher quality with Extra Smooth is totally worth the extra time. An optimized Moho project should render pretty quickly anyway. (FYI, I'm planning a video on this topic.)

Note: I always have Extra Smooth enabled by default; it might already be on by default, but check it.

To be clear, Extra Smooth doesn't actually correct the AA problem with the brushes, but it might make it look a little better and hopefully 'good enough'.