How to vector trace an area

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thestudentisready
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How to vector trace an area

Post by thestudentisready »

It would have saved me an entire day and probably come out better for something I just did if I could have figure out a better answer to this question:

If you have an area defined by borders... either from vector objects in AS or from image file.... something simple like thick black lines with white area in the middle... is there a way within AS to trace the interior or exterior and create a vector trace of it?

If, for instance, you have defined two circles with thick strokes than intersect (like mastercard logo)... and you wish to use them as guidelines to create 3 new shapes: The shape that is the left circle only, the shape that is the right circle only, and the shape that is the intersection...


BUT... you don't want your shapes to touch, and that's why you used the thick stroke on the guides... because you want a smooth even distance between your new shapes.

How would you do it? Weld points to create each new shape, then shrink it by a certain amount until it just lines up with the edge of the stroke?

Is there an easier way?

I have several effects that all rely on the answer to this, and I spent an entire day drawing tons of these vector objects by hand as I couldn't find a good enough way to trace them, so hoping someone has a better solution.
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slowtiger
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Post by slowtiger »

AS doesn't trace anything automatically. You need to re-draw by hand, which is called "tracing" as well.

There's applications elsewhere which will trace automatically, with results between acceptably accurate and totally unuseable. Illustrator, Streamline ... there's more like that, search for "vectorizing tools". Still all of them need further adjustment by hand.

Illustrator has some specialiezed tools for what you like to do, basically it's boolean operations on shapes: add, subtract, difference, and it can make an outline into a shape so you can work from that. I guess this would help you a lot.

I can "trace" stuff quite fast in AS, believe me, it comes with practice. Often I start with just a rectangle or a circle, then add points, adjust the curvature of some of them, reposition them, until it's good enough. I don't use welding because more often than not I get weird results.

Image

Here's my turn on overlapping circles. On a new layer, start with a circle in the size of the inner left circle. Use the script "draw > split curve" to add more points without changing the shape. Adjust curvage of two points to corner. Translate points, adjust some more curvage. Duplicate and mirror shape.

New circle in that inner section. 4 points only, adjust curvature until it fits.

This was done in 5 minutes. It's accurate enough for this size, for something bigger it needs more refinement.
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Víctor Paredes
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Post by Víctor Paredes »

You can achieve this even with less points
Image
It's all about position and curvature value of the points.

PD: you always can make masks. Sometimes it's faster and better than cutting smooth curves.
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thestudentisready
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Post by thestudentisready »

This hand tracing is essentially what I did... but there are dozens of shapes, and many keyframes, so it's quite tedious. The lack of a numeric readout for curvature value is also problematic for me since I need to recreate the first frame with all the shapes morphed and shifted to new positions.

It's been years since I looked at Illustrator, but I assumed it was more suited to the task.

Can anyone tell me a bit more about how masking would be used within AS to create these vector objects?
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Post by Rudiger »

thestudentisready wrote:This hand tracing is essentially what I did... but there are dozens of shapes, and many keyframes, so it's quite tedious. The lack of a numeric readout for curvature value is also problematic for me since I need to recreate the first frame with all the shapes morphed and shifted to new positions.

It's been years since I looked at Illustrator, but I assumed it was more suited to the task.

Can anyone tell me a bit more about how masking would be used within AS to create these vector objects?
As well as doing tutorial 2.6 about Masking and reading the manual, you can try checking out Heyvern's fairly comprehensive explanation:
Masking explained... I hope!

I agree with you, though. AS could really do with some boolean operation tools to improve efficiency when drawing and manipulating shapes. I've already started writing my own! Animators tend to be a fairly patient bunch, as it is pretty much mandatory for such a time-consuming art, but as an engineer, I can't help but want to make things more efficient, where I can see a need!
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Post by Mozbo »

The vector painting tools of other applications (like Flash), as well as the more accurate vector drawing tools (like Photoshop and Painter), show that it is not an impossible task, just one that takes additional application programming.

I would be happy if AS simply included Bezier Curve handle capabilities to adjust path points as desired...

The drawing tools in AS (along with severely limited import/export capabilites and relative keyframes) are one of the few downsides to an otherwise remarkably powerful application.
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Post by PARKER »

Mozbo wrote: I would be happy if AS simply included Bezier Curve handle capabilities to adjust path points as desired...
Im not sure about bezier handles, the fact that AS doesnt have them doenst mean at all that the drawing capabilities of the software are limited, i think you only need to get use to them also you can modify the curvature of the points the way you want by using the Curvatutre Tool.
Im my own experience for example, i have done almost everything in AS, cartoon, comic tv style, anime, comic book style, backgrounds, including cartoon backgrounds with just plain shapes, or some more complex with textures and even i have worked with an almost relistic style and i have never found myself limited because of the AS drawing tools.
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Post by Rudiger »

PARKER wrote:
Mozbo wrote: I would be happy if AS simply included Bezier Curve handle capabilities to adjust path points as desired...
Im not sure about bezier handles, the fact that AS doesnt have them doenst mean at all that the drawing capabilities of the software are limited, i think you only need to get use to them also you can modify the curvature of the points the way you want by using the Curvatutre Tool.
Im my own experience for example, i have done almost everything in AS, cartoon, comic tv style, anime, comic book style, backgrounds, including cartoon backgrounds with just plain shapes, or some more complex with textures and even i have worked with an almost relistic style and i have never found myself limited because of the AS drawing tools.
I agree. There is a reason you never hear experienced AS users complaining about lack of bezier handles. Once you're used to the different approach and have learnt to appreciate the benefits, you simply stop seeing the need for bezier handles. The trick is to start using more points than you would for programs with bezier handle control. This will give you more control as well as lessening the distortion of adding a point. In a way, the extra points are like bezier handles, except they are on the curve themselves!
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Post by PARKER »

Rudiger wrote: I agree. There is a reason you never hear experienced AS users complaining about lack of bezier handles. Once you're used to the different approach and have learnt to appreciate the benefits, you simply stop seeing the need for bezier handles. The trick is to start using more points than you would for programs with bezier handle control. This will give you more control as well as lessening the distortion of adding a point. In a way, the extra points are like bezier handles, except they are on the curve themselves!
True.I wouldnt like to see AS with bezier handles, its one of the things that make AS unique and different from other softwares.

Also some extra points can give you more control on your drawings, but again i can tell for own expereince that you dont really need to add too many points to get nice and complex curves in AS, therefore we couldnt say that the excess of points is an disadvantage when drawing in AS.
The only improvement i would ask for the AS drawing tols would be the free hand tool, it has been improved in v7 but flashs free hand tool and other softwares are still by far better than ASs, i dont use it too much any way, though.
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Post by Víctor Paredes »

Thinking about animation (which is this is about), an important thing about beziers handles is they would add two keyframes more on each point. Each one with X and Y values of position.
AS keeps that clean, each point has one position value and another for its curvature. that's great, but I suppose you don't noticed until you are animating.
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Post by Rudiger »

selgin wrote:Thinking about animation (which is this is about), an important thing about beziers handles is they would add two keyframes more on each point. Each one with X and Y values of position.
AS keeps that clean, each point has one position value and another for its curvature. that's great, but I suppose you don't noticed until you are animating.
I'm not advocating adding bezier handles to AS or anything, but you could make them automatically generated, like AS does now, unless you explicitly move them and create a keyframe for them. That way, if you didn't want to worry about them you wouldn't have to, but people who wanted the extra control could have it, especially when drawing more for bone animation than point animation.
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Post by sbtamu »

selgin wrote:Thinking about animation (which is this is about), an important thing about beziers handles is they would add two keyframes more on each point. Each one with X and Y values of position.
AS keeps that clean, each point has one position value and another for its curvature. that's great, but I suppose you don't noticed until you are animating.
Wouldn't 2 extra key frames at each point add massive amount to render times?
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Post by Rudiger »

sbtamu wrote:
selgin wrote:Thinking about animation (which is this is about), an important thing about beziers handles is they would add two keyframes more on each point. Each one with X and Y values of position.
AS keeps that clean, each point has one position value and another for its curvature. that's great, but I suppose you don't noticed until you are animating.
Wouldn't 2 extra key frames at each point add massive amount to render times?
I doubt it, especially since you would probably need fewer points and you wouldn't need to do the bezier point calculation (which is quite complex for AS7, by the way). Also, like I said above, you could have control types for each point, eg corner, auto, smooth, independent, etc, so you only use the extra keys when you need them.
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Post by crsP »

I think you guys have it confused as to the advantages of bezier handles in animation.

Rudiger is correct in saying to replicate what you can do with bezier curves, you need to add more points. These points act as 'curve controls' to alter the flow of the curve. Anime Studio's curvature tool cannot be the end-all of curve control as it works symmetrically. I.e. if you make one side of a point curved, the other side must be curved, and similarly with straight. So if you want a curved line adjacent a straight line, you must add a point to control the curve.

The first problem with this is in the 'drawing' stage. As we know, adding points affects the lines. So you got to add a point, position it, then adjust it's curvature. The second problem is what selgin wrongly attributes to bezier handles. That is, if you move the 'main point' you must move the curve control points to maintain the correct curve. What selgin [and others who agree with him that you need to add keys for these control handles] doesn't realise is that bezier handles work in a hierarchy with the 'main point', as children of this parent. And if you focus your mind on another hierarchical relationship in Anime Studio, for example bones, you will know that you can move all subsequent child bones by moving the parent bone, and therefore no keys are needed for the children. The same rule applies to the bezier handles. By keying the point, the handles need not be keyed, as they inherit the relative position of the parent. So that argument falls apart.

Whereas, by having extra points to control the curve flow [as has to be done currently in AS] you MUST move those points or your animation will look like there are pins stuck at the positions of the curve control points. This leads to more work.

Another thing you can do with bezier handles is change the flow so essentially is looks like your vectors are rotating around the point [the point being the pivot]. Imagine the possibilities in animation! There is no way to do this in Anime Studio, as far as I know. You can't rotate a single point.

See the many advantages of bezier handles? I know you guys just automatically assume that people who want bezier handles just want AS to be like program x. That may be the case with some, no doubt, but I can assure you much thought and experimentation has gone into this on my side. I was, way before this thread, going to make my case with screen grabs and the like, but I had to come here as this is the second time I saw selgin write that you must key these handles. Which is false information. And Parker, we want bezier handles ADDED to AS, NOT replacing it's current tools, like Rudiger say, for those who need it. I believe once you guys have hands on use of bezier handles in AS, you will see the benefits and advantages. Also the freehand tool is worse in ASP7 - I plugged my wacom bamboo and tried to use it in ASP. You don't see a preview of your line thickness [just a thin red line] and I have a third party script tool which does show the thickness in the preview red line, so it's not my operating system or hardware which is at fault. And you can adjust the sensitivity, but lm took that out in version 7.

Finally, mozbo you are very confused. Photoshop and Painter are primarily bitmap tools. They both have simple vector tools. So I don't know what you mean by "... as well as the more accurate vector drawing tools (like Photoshop and Painter...)"
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Post by Víctor Paredes »

Sorry, I didn't explain it well. I never wanted to tell you must add keys everytime. It's just with beziers you would have four animated cordenates to control (X and Y of each bezier handle) instead of one value like it's now with curvature.

Maybe you are right and I'm just afraid to be AS becoming another software. If handles were implemented as a complement of the current method for curvature I think I wouldn't deny.
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