Blend spines

[DougKatz]

After so many years with Illustrator, I'm shocked by an accidental discovery.

I've drawn two ellipses with different color fills, no strokes, then blended them. I've taken the scissors tool to the no-fill, no-stroke spine. After making a cut, the blend remains intact!

I can reposition the "separate looking" blends, move individual end points of each spine freely, add curvature to each spine, add points, make additional cuts to the spine(s), change the fills and strokes of the blend objects, add objects to the blend (from within the Layers panel), use the Reverse Spine and Reverse Front to Back commands, move separate bits of the spine to different artboards (when I direct select the bit's spine). Nothing seems to "break" the blend!

How in the world does a chopped up, mangled and mutilated blend+spine retain integrity like this?! Has this always been possible? Am I pathetically late to a party that everyone else has been at for years and years? Jeez.

[tromboniator]

I just tried it in CS3 and it works there, too. No, it never occurred to me to try that. I would have dismissed the idea as absurd. Now I can't wait to play with it. Thanks for sharing this, Doug. I certainly didn't know about it.

Peter

[Mario Arizmendi]

Wow...

Tried here CC 2017, its amazing how it works even if the spine is breaked apart in many pieces

Some Adobe engineer here to explain how is this possible?

[DougKatz]

The discovery itself was a little disconcerting. But the prospect that I was the only one who didn't know about it made it worse. So I thank you two experienced artists for assuaging my embarrassment!

Like Peter, I'm now wondering how this mysterious capability can be put to use.

[rcraighead]

That is amazing, Doug! I had no idea. Would never have thought to try it. Works great in CS5 too. I think I'll play.

[Doug A Roberts]

i love that this is new to all of us. that's really cool, good find Doug.

[Jacob Bugge]

Indeed, thank you for sharing, Doug.

I believe Illy may be quite unaware of (some of) her hidden talents.

[Ton Frederiks]

Never knew that, glad you found it, Doug.

Blends were introduced 30 years ago with Illustrator 88, but they were not live and had no spine.

Live blends appeared 10 years later in Illustrator 8, I suppose this behaviour has been around since then (but I cannot check that on my machine).

[John Mensinger]

Surely no one would have expected that to work the way it does. Great find, Doug!

[Jeff Witchel, ACI]

Interesting! But if you replace the Spine with a closed path (such as a circle) and then cut this new Spine, the Blend objects do move to the beginning and end of the open path.

Check out this video: http://www.jeffwitchel.net/2011/11/blend-tips/    You'll see what I'm referring to at about 3:00 minutes into the video.

[Jacob Bugge]

Quite true, Jeff.

I believe many of us have used that cutting for many years, without realizing the hidden world behind it.

This quick search went more than 8 years back (the present forums preserving threads goes 9 years back, so I belive there are far older ones):

https://forums.adobe.com/search.jspa?q=cut+circle+blend+start&place=%2Fplaces%2F1383787&depth=ALL&au...

[DougKatz]

Interesting limitation on this capability:

Once the spine is cut, I can't alter the stacking order of the separate segments. So while X and Y movements of an individual blend "segment" are remarkably modifiable, Z movements are fixed. This may be entirely logical since – despite appearances – splitting the spine doesn't seem to change the blend's unity. (But now I'm off in areas about which I know nothing.)

[Kurt Gold]

You cannot alter the Z-order by using the Arrange commands, but you actually can change the Z-order by using the Layers palette.

And you may then see some other astounding behaviours of the needy hashed blend.

[DougKatz]

Yes, Kurt! I did actually discover this after posting about the fixed Z-order of split blends. Dragging the spine paths in the Layers Panel above or below each other actually moves the blend objects themselves from spine to spine! Other astounding behaviors.

[ceyhun_akgun]

Illustrator Blend functions have been in the upper level for a long time. Years ago, when I wrote an article introducing the CS2 version, I gave a special mention to Blend functions.

Nowadays, with the introduction of the Gradient Mesh function, examples of illustrations made with Blend have been reduced.