Technical question about control points

There was a time when I was certain of the number and location of control poiunts in a given character in a typeface I'd use, because Program X or Program Y flashed a little thing on its splash screen "reading font metrics"...

Does Xara even read font metrics at all?

The reason I ask it that frequently I need to modify a glyph to make a logo or something. And Xara Designer 11 produces way more control points than I'd expect or want whenever I do the Ctrl+Shift+S thing:

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This is a fair comparison above: Here'a glyph shown with its original control points in FontLab (a font editor), at bottom. And then there's the glyph (top) when reduced to a path in Xara.


Why? And is there a way to curtail this excessive control point thing?

TIA,

Gary

Metrics? Yes, to a point (no pun intended). I don't think that control points are part of a font's metrics. Maybe, but I have never thought of them that way.

Fundamentally, unless an application actually can utilize and draw curves according to whether a font is TT or OT, I think that the addition/subtraction of curves are needed. I would be extremely happy if application X would implement the control nodes as smooth curves where appropriate instead of cusps when type is converted to curves.

I also think that this may be character related. In the screen shot below the on-curve points line up fairly well and the cusp handle adjustments match the off-curve points well.

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Mike

Mike, you're saying that the conversion from glyph to path involves absolutely no culling of control point info?

Seems bass-ackwards to me when the data is already mapped out in the file.

Thanks, though.

Life sucks sometimes...

-g

No, I didn't mean that. In my example, the on-curve points as shown in my editor and the cusp points from XDP'S conversion literally are aligned (some are simply very close). The off-curve points from the font editor are still seen when they are outside curves.

Techically in my example, XDP has about 30% fewer points than the font editor if the on- and off-curve points are added together. XDP has 50 some points on the same character as in my font editor, which has 95 points.

What I was getting at, in my example XDP converted that A character with fewer points than are in the font editor. Your example has more points than your font editor. So perhaps it all depends on what character is converted to curves. Maybe even whether it is a TT or OT, seeing how technically they are different types of curves.

Thanks for your explanation, Mike.

However, I still do not understand—and the lack of understanding is my own problem—why, if a program can "see", parse, understand a curve, why it doesn't see the tension and bias values of bounding control points and just use them when a gylph is "decompiled into a simpler vector form.

In any event, it's a chore to eliminate unnecessary control points!

My Best,

Gary

Dunno the answer, Gary.

It works in the reverse--I can go from XDP or AI or CD and the on-curve control points are near identical in my font editor. So I think it can be done. That said, most of the characters I tried other than that 'A' convert fairly well.

What font are you using in your example?

Okay, I did what should have been obvious from the get-go: it's no secret that Adobe Illustrator "pre-rolls" font data so there's not wait when the program loads, so you can get down to work, unlike Photoshop.

I used a glyph from Zapf Dingbats. I think based on simplifying the glyph in Xara and in Illustrator, that Xara doesn't read all the font set data. Why else would Illustrator show a decompiled glyph as being node-for-node the same as it was designed (in the FontLab view)?

I'm not trying to give the programmers at Xara a hard time. I know how to be a jerk using far less energy than here!

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I'd love to know the secret recipe Illustrator uses and see if it can't be applied to Xara. I'm having a devil of a time manually reworking glyph are so I can use fewer control points (thus fewer bumps in smooth "knots") in certain Xara pieces of Art and outlnes for modeling.

Sigh,

Gare

This is what I get in XDPX11 when that character is converted to shapes/curves:

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...so this exercise can be repeated with consistency, mwenz! This is exactly my result.

Which is an exact, inexact replica of the structure of the glyph.

The reason I'm harping on this is that for the most part, modeling programs tend to put a kink in the outline of a 3D extruded shape when the control point isn't flawless, the number of control points are succinct) and the properties of a curve are correct.

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The fewer connections I have, the less of a chance I fnd a bum one, as shown above.

And all of these excessive son-of-a-guns have cusp, not smooth connections, if you or anyone else can confirm.

Harumph. And it's only Tuesday!

:)

-g

I think my screen shot shows the control points as per AI, not your screen shot of what your XDP is doing.

To edit...yes, they are cups and not smooth points. I think I have mentioned that above. That is the only improvement I think is needed. At least in my conversion of type to curves.

To keep the record straight, your and my "conversion" in Xara yields 43 (or 42, one is overlapping, hard to tell) control points all with cusp properties. This is what I see in your post #8 where you mention Xara Designer 11.

What Illustrator did for me was to map control points precisely as originally created in a font editor, a total of about 23 control points. There are almost twice as many control points created from the original glyph in Xara; this needs work, Mike.

Do people want to have to edit x number of nodes, or 2x when a gylph is simplified?

Rhetorically yours, and congratulations again!

Gare

31 points in each XDP X11 and AI CS6.

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It is your conversion that has the large number of points.

I'll leave this conversation now...

Quote:

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Originally Posted by mwenz

31 points in each XDP X11 and AI CS6.

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It is your conversion that has the large number of points.

I'll leave this conversation now...

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I'm going to leave it, too, Mike! :)

I guess my results are either non-reproducible, or no one minds a verbose method of creating paths from Type 1 encoding.

:-O

Well, we can both agree that, like Illy, the curve points need to be smooth points instead of XDP's cusp points.

What is tedious for me in XDP is the lassoing of the points that should be smooth points and clicking on the context toolbar to make them so. The result is correct 99% of the time. But sometimes the curve is altered unacceptably.

To stray from my original point/lament/query (and I will post this on the Wish List thread), there are a number of behaviours I'd like to see corrected and/or enhanced in the next version of XD:

• The ability to lasso nodes along a path, and then scale and rotate only this segment of the overall path. CorelDRAW offers this and has so for almost a decade. It lets you scale only a part of a path; I found this useful to adjust the size of only the feathers on a fancy arrow I drew.

• I don't quite understand how FontLab version 4.5 from a decade ago can be told to optimize a path, and it does so with no noticeable change to the path, even though it can dramatically change the number and position of nodes.

• I feel (and am often alone when I do!) that it's time for a node and path editing tool, a dedicated one. The Shape tool has become far too robust as a drawing tool to be used to quickly change stuff. CorelDRAW's editing tool can alos be used to select stuff on the page you can ten edit. You cannot do this in Xara eith rthe Shape tool...you need to switch to the Selector tool, and then switch back.

When you have repetitive tasks, you absolutely need to get to the root of your design. And the root of vector design work is the path/control point physique.

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I think Corel Corp. was merciless in their inspiration for new features back in the 1990s: they picked and chose from Xara's features.
Isn't turnabout fair play?

-g

I swapped out the space bar for changing to the Shape Editor tool long ago. That way I can leave my hand in the same relative position when changing back and forth between the pointer and shape tool. Not ideal, but far quicker than going back and forth between the V and F4 keys.

Smoothing. I think this can be enhanced. I get decent results using the smooth curve setting on the context tool bar.

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I would like a toggle to go from the rectangle select to a lasso select when using the Shape Editor...maybe there is one but I cannot find it.

Good calls and I hope they wind up on The Wish List, pal.

Gary