- [Voiceover] Now, the truth of path finder operations
is they're a little long in the tooth.
They were originally introduced in Illustrator five.
And the guys at top, these so-called shape modes,
they've been upgraded over time but the others have not.
And as a result, they're a little finicky sometimes.
They tend to really like filled, closed,
path outlines, so filled shapes.
So notice here that we have these daggers and double daggers
following the names of some of these operations.
The dagger means the operation is incompatible
with unfilled paths, and the double dagger means
that it has problems with open paths.
And so as you can see, trim all the way
through outline, have problems with both.
Divide has a big problem with open paths.
But minus back has no problems at all
and neither do that fab four up here at the top.
So, just to give you a sense of what I mean by all this
I'll just go ahead and zoom in on my unfilled paths,
and I'll marquee both of these guys here so they're stroked,
they're not filled, they are closed path outlines.
So it's the same square and ring
that we had before, just without a fill.
And now, I'll go ahead and click on a representative
path finder trim, and as you can see, I get an error message
telling me this path finder operation requires filled paths.
And that's the same error message
you're gonna get from merge as well.
Crop will work, technically, but it doesn't do
what it's supposed to, notice that it ends up
giving us back two circles,
and if I ungroup them by pressing Control Shift G,
or Command Shift G on the Mac, and then just tap the D key,
you can see what we have is a compound path
with a circle inside of it but it's no longer a live shape.
So we just kinda wrecked the path outlines.
Alright, so I'll just go ahead and undo back.
I'll be doing a lot of undoing here.
Next comes outline, which does its job except for the
fact that it just gets rid of the strokes.
So if I were to tap the D key, we can see
that everything's here, and I could pick it apart too,
by pressing Control Shift G or Command Shift G on a Mac,
and then just start dragging these guys apart,
and so you can see, we still have the separated paths
just like we did before, it's just that we lost the strokes.
So it's not terrible, just a little bit of inconvenience.
Alright, I'll go ahead and undo that again
in order to put things back together.
And let's try out divide, which works exactly
as it's supposed to, by the way,
and so, if I was to press Control Shift G
or Command Shift G on a Mac, in order
to ungroup these shapes and start moving them apart,
you can see that they are indeed the shapes we were
looking for, and of course we have
Mr. Negative Space as well.
Alright, we'll go ahead and undo all the way back
till we get the original shapes,
and I'll just demonstrate very quickly,
that minus back works exactly as you'd hope it would,
and so do, if I press Control Z or Command Z on a Mac,
so do all of the shape modes,
including, for example, unite, works just great.
Alright, now let's check out what happens with open paths,
if I go ahead and marquee these guys,
both of which are open, as you can see.
Both trim and merge are gonna
do the same things we saw before.
Crop is gonna result in a similar failure
to what we saw before as well.
And then outline is gonna do its standard thing
where it divides all the lines
but it throws away the strokes.
The one that behaves very strangely in this case,
differently than we saw with unfilled paths,
is divide, which just plain fails.
And so you can see here, even if I marquee this region
all I get is these two path outlines right here.
So there's not a bunch of hidden stuff,
or anything like that, it's just that
the operation doesn't perform the way it's supposed to.
However, if I go ahead and undo that, you can see
that minus back works just great except
it does deliver a closed path outline.
That's the thing to bear in mind.
So anytime you apply minus back or any of the shape modes
to unfilled path outlines,
they will deliver closed path outlines,
which I can also demonstrate by clicking on unite,
which produces this very interesting effect, right here.
So, just be aware that many of the path finder operations
do not work with unfilled or open path outlines.
And, if you want my summary here, this would be it.
My favorite path finder operations, the ones I use
on a regular basis, are unite through exclude, up here
in the top row, as well as divide and minus back,
which are the first and last icons in the bottom row.
With the one caveat being that divide
is not gonna serve you well with open path outlines.