[Locked] How do I shade or paint "inside the lines" with Illustrator?

[Parklife444]

I'm a longtime Illustrator user, and have yet to figure out an elegant solution for perhaps my most common illustrator task. So, at long last, I'm resorting to the forums.

When one paints in Photoshop, it's common to use the magic wand (or some selection tool) to select a region so that you cannot paint outside of it. Let's say I want to add a shadow or highlight to a sphere -- I select the fill color of the sphere, and then can drag my brush along the perimiter of the selection, which keeps my shadow entirely inside the sphere. This is especially important for cartoon-style drawings where you want sharp shadows or highlights.

It doesn't seem there's any way to do this in Illustrator (using a freehand style of drawing, with a Wacom tablet or the like). The best solution I've found is to use live paint, which allows you to easily select any color areas that spill outside of a line (because live paint identifies those areas as separate entities). You can then simply delete the unwanted color. It's also possible to use the pathfinder tools to unify only overlapping areas, but this can get even more cumbersome if your illustration is complex.

My hope is that someone has a better way -- a plug-in perhaps, or something really obvious that I'm overlooking. Thanks you in advance. Also, I'm not interested in ways of doing this using the pen tool -- I know how to add shadows in that fashion. The goal is to find a way to quickly paint freehand, using a tablet and the brush tools.

P.S. I realize it's possible to simply bring the file into Photoshop, but then you're not creating a vector image, obviously.

[JETalmage]

Odd question from a longtime AI user. When drawing in programs like Illustrator, you are creating objects, not merely recoloring existing pixels. So the objects you draw either have to be shaped exactly like you want them to show, or you have to use other paths to mask them or trim them.

This PDF shows one method of "painting into" a masked area. It was done as an example of exploiting the so-called Isolation Mode which appeared somewhere around version CS2, as I recall. It sort of emulates painting with an airbrush inside regions masked by frisket material, by drawing paths with a Brush appearance and a blurr Effect applied inside nested clipping paths.

JET

[Parklife444]

Hi JET,

The doc you sent is helpful, but it essnetially relies on clipping masks -- another cumbersome feature that is ultimately less useful than manually shaping the shadows or highlights manually.

For the record, the question I'm asking isn't actually that strange. Illustrator already has the ability, heightened greatly with Live Paint, to allow you to select certain color regions. I'm simplyi asking if it's possible to constrain all drawing to within a given color reason, which would be helpful for a number of reasons. The simple fact is that one often wants that "human touch" to the shading, which is easiest to achieve using a pressure-sensitive tablet. However, without the ability to constrain the drawing, you're often left with quite a bit of clean-up work, which seems entirely unnecessary given that Live Paint is ALREADY recognizing which color areas are inside a shape and which are outside of it. I'm just wondering if there's a way to automate the process.

[JETalmage]

For the record, the question I'm asking isn't actually that strange.

It's strange in that one would expect a long-experienced Illustrator user to understand what I already mentioned: That "painting" in Illustrator amounts to creating additional objects. To "contain" those newly created objects (be they generated by swiping with a stylus or not) to other pre-existing shapes entails masking, because each swipe with that stylus is creating a new object; not just "recoloring" something that already exists.

The same principle applies to flood-fill features. Illustrator's flood fill feature, so-called "Live Paint," is effectively "autotracing" regions bounded by existing paths to create new paths and then giving the new path a fill. But Live Paint doesn't include any functionality that would let you swipe with your stylus (creating a new object) and then auto-combining it with the pre-existing region in which you painted leaving just the intersection of the two paths.

As demonstrated, you can emulate that kind of behavior by exploiting Isolation Mode. Another way is to apply Pathfinder Effects or Shape Modes to Layers or Groups and create your new objects within those Layers or Groups. But it all still comes down to one form of masking or another until you Expand, Flatten Transparency, etc.

JET

[Parklife444]

Ok, no, it's not strange. Obviously the computation would run somethin glike -- you create an object/shape that both overlaps a color region and exists outside a color region; because you've told Illustrator "draw only in color region" it determines which area lies outside the color region (which it ALREADY DOES with Live Paint) and then deletes that offending area. Thus you're left with a neat little shadow or highlight exactly where you want it.

I understand that this may be impossible as Illustrator exists today (I'm out on a limb asking for support on this one), but the feature is both entirely feasible, and relying on a computation Illustrator already performs.

Also, in your latest response you mention two things I've already said I'm aware of and not interested in -- the isolation mode exploit is in fact using clipping paths, which isn't helpful, and pathfinding tools again qualify as clean-up, and can become cumbersome if the illustration is too complex.

I appreciate your attempt to answer my question, but I feel that what I'm asking is valid, and that someone may have a good trick for doing what I'm asking -- hopefully in Live Paint, though again, I haven't found a way to do this. In any case it would be a feature that would save me a lot of time, and again, seems easy to impliment.

[Mylenium]

I tend to disagree with you, James. From a mathematical point of view there is no reason that such a feature could not exist. Per se there is no limitation on how you calculate a fill just as there is no reason to limit gradations to a specific number of colors. It doesn't need to be an "object", just some kind of data structure that provides a spatial reference, which, as a pre-requisite would be constrained by the containing object. I think it's a different problem: Users and developers of vector drawing programs have so gotten used to the crookedness of some features and implementations, that it has become "industry standard" (whatever such awful words mean) and nobody, really nobody goes looking for solutions outside those trampled down paths. As I said many times already - the innovation level in vector drawing tools is about the lowest you can get anywhere in the graphics software industry and if not someoen starts to do some serious out-of-the-box thinking, it will be this way forever.

Mylenium

[Wade_Zimmerman1]

Although what I suggest can work at a combination of layer and object masks that emulates the way a selection is made by photoshop can work as a temporary mask the expands automatically when deselected.

It used to be a repeated feature request.

Akin to the masking tools in After Effects except that the mask act as a temporary select, which could also be saved similar to an alpha channel without the over head.

This is a good feature request and it would work particu;ary well with the blob brush and the eraser tool.

[Parklife444]

Thanks Wade -- I think what you suggest is probably the most elegant solution available today. Yeah, I might put it in the feature requests, as it seems like what I want isn't possible. My issue isn't that constraining drawing to a shape or color area can't be done at all, it's that it's a cumbersome process. It's funny because this is such a common process in Photoshop, and some artists I know choose to simply abandon pure vector art for the speed and ease of shading in Photoshop (when possible). It seems like Illustrator more or less already has the capabilities to do what I want, it's just not an option. Again, they could simply add a proper magic wand option (and other selection options) to the Blob brush and Live Paint.

[Guest]

(I posted this under your thread in the Feature Request forum before seeing this thread.)

Not a challenge to the request but a question:

Why is it more efficient to draw a marquee in Photoshop (which I do often to create highlights and shadows there) than it is to draw a comparable, closed area with the freeform pencil tool or blob tool, then filling that shape with a tint or shade (which I do often to create highlights and shadows in Illustrator)?

I appreciate that in the Photoshop case, you're not necessarily creating a new "object" (i.e., Photoshop layer) and in Illustrator the pencil tool does create a new object. But why is that problematic? No new layers need be created, no masks, no Live Paint objects, no pathfinders.

And with Illustrator's blend modes, opacity controls and feathering effects, the flexibility approximates Photoshop's that much more closely.

[JETalmage]

Doug,

Park wants the shading object (the brush or blob stroke) to be automatically cropped to within the object being shaded--as if painting into the content of a clipping path, but with the new object actually being cropped, not just masked.

Example:

Select a red-filled circle.

Swipe along its edge with a marooon blob or brush.

The swipe is automatically trimmed where it extends beyond the bounds of the circle.

JET

[Guest]

Yes, he's clarified that for me in the Feature Request forum.

[JETalmage]

From a mathematical point of view there is no reason that such a feature could not exist.

And where did I say that "such a feature could not exist"? Park asked how to do something similar to what he does when painting inside a selection in Photoshop. He didn't say he was making a "feature request." And nowhere did I say that such a feature would be impossible.

Of course it could be done. It would be much the same as a re-work of path operations (Pathfinders), just as many "new" features of Illustrator are just re-works of existing functions.

Example: FreeHand's Combine functions work better than Illustrator's. Applying the Intersect function does not wreck the existing fills and strokes of the involved paths. You have the option to press a modifier key to retain the origninal objects. So, sure, such a thing could be programmed to auto-trim the painted path to where it intersects the target path. But Illustrator has no such feature. I was just offering the existing workarounds, and expressed surprised that someone long experienced in Illustrator didn't know that.

JET

[Wade_Zimmerman1]

Clipping Mask?

[Parklife444]

Clipping path, sorry.

[Parklife444]

A HUGE thanks to the fine developers and Adobe who implimented this exact feature in CS5!

[JETalmage]

...who implimented this exact feature in CS5!

That exact feature? How, then, do you reconcile that with your earlier statement:

...the isolation mode exploit is in fact using clipping paths, which isn't helpful...

When I view the teaser demo of the new feature, I see the extraneous portions still existing-- i.e.; merely being masked. Sure looks like a clipping path at work to me. I'm not saying having an interface dedicated specifically to working that way isn't more convenient than my pre-CS5 workaround; but it still looks structurally like much the same thing--same old untidy masking, not actual triming.

JET

[Parklife444 · Accepted solution]

All I wanted was precisely what Adobe implimented -- a paint inside the lines features, similar to creating a mask/selection in Photoshop so that you can't accidentally paint outside of a shape or color area. Even though the feature is essentially automated clipping masks, it frees up my workflow. Also, it's not a bad thing that it still maintains the excess data -- namely the bits of paint cut off by the clipping mask.

[_scott_]

Illustrator CS5... the Bristle Brush.. and maybe Paint Inside.

[mallikatandon]

Hi!

I couldn't bother reading the rest of the threads so I'll tell you something that I do.

Make a closed path over the area within which you wish to constrain the brush lines. Remove the fill and stroke.

Duplicate that closed path.

Select both paths and make a clipping mask.

Select that clipping mask, go into isolation mode and then use your brush.

Happy brushing!

[chun_hinl67684697]

Illustrator: Draw Inside of Objects - Tutorial - YouTube

Does this help?

[jbdeborman1234]

In case it helps : the function is available in Adobe Animate : Brush > Brush Mode > Paint selection.