straight lines are actually bent

Markku · Post by **Markku** » Tue Apr 26, 2005 10:36 am

Sorry, I know this sounds like I'm really trying to find faults in this program but really I'm not.

I am new to it and trying to get a grip of it.

I found this weird thing about straight lines.
When I draw a rectangle and zoom very, very close to a point I can see that the lines that I thought were straight are infact a bit bent.

I tried to use the peak tool and curvature tool on them, but the lines "refused" to be perfectly straight.

Has anybody else seen this feature?

Toontoonz · Post by **Toontoonz** » Tue Apr 26, 2005 1:15 pm

Yes, I see the same thing if I really zoom in a lot.
I drew a rectangle (four points) then with the Script tool Draw > split curve, I added 5 points between the 4 original points.
The Y-axis value should be the same for all the points, but they aren´t.
From left to right, the Y-axis point values:
Pt. 1 = 0.3333
Pt. 2 = 0.3335
Pt. 3 = 0.3336
Pt. 4 = 0.3337
Pt. 5 = 0.3336
Pt. 6 = 0.3335
Pt. 7 = 0.3333

So the line is not perfectly straight, but rather bows (very,very little) up in the middle.

7feet · Post by **7feet** » Tue Apr 26, 2005 2:46 pm

That's another one of those "it's gonna be a mighty strange day if you actually see that" kind of things. Part of that relates to how the minimum curvature of a point is set as 0.0010000 (where the standard curvature of a rounded point is 0.3000000. It was, I'm sure, chosen as a nice simple number, and maybe it saves some extra math in there. I had made a modification of the curvature tool that shows you the numerical curvature for a point or points (it's posted somewhere in the script forum). I had raised the default maximum curvature, but never really thought of the bottom end, even though I had noticed that effect before when trying to perfectly align vector layers to make 3D shapes. If it's really that much of a concern, I can tweak it a bit more to drop the minimum curvature, although I don't know how far you can go before something might try to divide by zero and give Moho a fit.

Markku · Post by **Markku** » Wed Apr 27, 2005 4:19 am

I don't know if it's due to these curved lines or inaccurate grid snapping, but I'm having really hard time outputting rectangles with one solid color.

I sometimes manage to produce a 1 px high box that looks like its color is solid, but closer look at the screen grab shows its not.

If there is some fundamental thing that prevents lines to be exactly straight then I think there is no reason to tweak the decimals closer to zero if the ultimate zero can not be reached.

Then I just have to accept that Moho can not be used for projects that require pixel level accuracy.

Post by **Lost Marble** » Wed Apr 27, 2005 4:43 am

Not to say that it's not important, but what about the nature of your project requires this pixel-level kind of accuracy.

Markku wrote:I sometimes manage to produce a 1 px high box that looks like its color is solid, but closer look at the screen grab shows its not.

You're the creator of this image, and you need to look closely to see these errors. I assume you're looking at a still image. Throw some animated movement into the mix, and is it really going to make any difference to your audience if something is off by a pixel?

Like I said, I don't mean to say it isn't important for your particular animation - maybe it is. But for the things Moho was designed for, cartoon-style animation, no one should ever notice a pixel difference here or there.

7feet · Post by **7feet** » Wed Apr 27, 2005 6:02 am

The "File>Render" command (or <CTRL>+R) always uses the antialiasing, which is what I believe your seeing. If you render an animation (i just tried it with a length of 2 frames) with the anti-aliasing turned off, it's just as clean and proper as you could want. I made 3 filled rectangles, 1x5 pixels, one pixel apart one above the other. Zooming in on the render (I did it PNG, 800x600 project size), it was spot on. Antialiasing is always goint to mix up colors, especially at asingle pixel level. It's kind of the definition, but perhaps it would be useful to be able to set the degree of anti-aliasing without eliminating it altogether. If you are exporting to Flash, then it's a non issue.

I also went into the Peak Tool script and kicked the minimum curvature down to 0.0000000001, drew a box 3 times the size of the work area, and used the modified Peak tool on all 4 points. At the center between any 2 points there was perhaps a deviation of 3-4% of a pixels width. With that, you could zoom from seeing the entire rectangle to a single pixel and not see a thing move.

For an example, this is a single pixel grid (blown up a lot, of course), exported as a TGA (the PNG compression mucked things up a bit), straight and with anti-aliasing enabled

Quite a difference at that level.

jahnocli · Post by **jahnocli** » Wed Apr 27, 2005 7:52 am

Can you hear that sound? It's angels dancing on a pin head...

RASH · Post by **RASH** » Wed Apr 27, 2005 9:30 am

It seems I was not at all being as complicated as I assumed. This thread is top league complicada in extrema...

Subpixel accuracy in a cartoon animation program... Guys, what are we talking about here?

Toontoonz · Post by **Toontoonz** » Wed Apr 27, 2005 10:08 am

There is a style of animation where people build the animation pixel by pixel.

Here is are examples at this German website:
http://www.postertronic.de/flash/home.html

RASH · Post by **RASH** » Wed Apr 27, 2005 10:39 am

Toontoonz wrote:There is a style of animation where people build the animation pixel by pixel.

I understand now. OTOH there must be programs better suited for computer aided pixel pushing than Moho.

It seems to me that Moho is more of a drawing program (equivalent to pencil drawing) and less of a painting program (equivalent to brush painting). Of course, in traditional visual arts it IS possible to paint with a pencil and to draw with a brush, so something simular will probably apply to the new arts as well. But isn't that making things unnecessary complicated?

Markku · Post by **Markku** » Wed Apr 27, 2005 11:28 am

All of you are right that we are trying to split a hair here.
When I began to post this question I wasn't sure wether the problem was due to my poor Moho skills or was I expecting too much.
Then after 7feet's first reply I understood I was expecting too much and I wrote that on my reply.

Here's some general background on the project.
The website's general look is quite strict pixel look. Now I'm at the stage where I need to make a flash on top of the site's main image. The visual components in the flash need to be inline with the sites overall look, thus there needs to be vector made pixel-looking elements flying around.

And this hassle begun as I first thought I could maybe generate the final version in Moho, then I saw these shortcomings of which I asked all of you about.

Now its clear to me that I can use Moho in the general construction of the animation, but I need to tweak the elements quite a bit afterwards in MM Flash. Especially when the movement ends.

Finally I have to say that Moho is very appealing to use in animation. Much better than Flash.

Please, if you may comment on my question about the coordinates and maybe do something about the grid snapping.

Thank you very much!

Toontoonz · Post by **Toontoonz** » Wed Apr 27, 2005 12:56 pm

RASH wrote: It seems to me that Moho is more of a drawing program (equivalent to pencil drawing) and less of a painting program (equivalent to brush painting).

Personal opinion by me - but I look at Moho as more of a very robust 2D (vector) animation program than any type of drawing or painting program.
It is awkward to draw and/or paint in Moho. (Plus one cannot export Moho vector art out of Moho as a vector-type file.)
If Moho could just import an Adobe Illustrator file that matches the file in Adobe Illustrator....
Just my 2 cents.

RASH · Post by **RASH** » Wed Apr 27, 2005 1:04 pm

Markku wrote:Please, if you may comment on my question about the coordinates and maybe do something about the grid snapping.

After you've completed your drawing in a single layer, you can turn off grid snapping trough the menu (View -> Disable Grid Snapping) and then align the completely selected drawing with the grid.

However, as you can see from this screenshot

the alignment with the frame edges is perfect, although the grid seems to indicate something else. Objects seems to snap at the correct position, while the grid is offset somewhat.

RASH · Post by **RASH** » Wed Apr 27, 2005 1:09 pm

Toontoonz wrote:It is awkward to draw and/or paint in Moho. (Plus one cannot export Moho vector art out of Moho as a vector-type file.)
If Moho could just import an Adobe Illustrator file that matches the file in Adobe Illustrator....

I couldn't agree more.

I could even go further, but then I'd risk this message to be deleted by LM, just as it was the last time I suggested something similar in another thread

Post by **Lost Marble** » Wed Apr 27, 2005 5:18 pm

RASH wrote:I could even go further, but then I'd risk this message to be deleted by LM, just as it was the last time I suggested something similar in another thread

I think I've only ever deleted one thread on this forum, ever. And that was because it broke down into some pretty petty name-calling. I don't remember the original topic of the thread, but I would not have deleted it because it was about Moho's drawing tools.

It's pretty clear that some people prefer Adobe Illustrator's drawing tools. I have no wish to censor that opinion - you're free to not like Moho's drawing tools if you wish.