7 replies to this topic

[David Medeiros]

I'm trying to accomplish the stream taper effect that Top Patterson uses on his National Park maps (and seen in a few other places as well). I have the basic idea down, but always end up with odd looking rivers where the new taper effect does not progress uniformly down the line but kinks and folds over itself. Here's my work flow accompanied by images:

Draw line at desired river width, convert to outline, pull one end in to create a thin wedge (in this case the wedge only goes to bout 30% of the line):


Verify "Non-zero winding fill rule" set for art to be brush (default on my system):


Apply as new art brush:




Apply brush to imported river line-work (NHD stream data simplified to 98%):




As you can see this obliterates the line. Not the taper effect I'm after. What am I doing wrong?

Thanks,
David

[razornole]

Is the line joined?

kru

[razornole]

I meant prior to outlining the stroke. It looks like a fill issue/artifact to me.

kru

[David Medeiros]

The line is joined. The same thing happens if I draw a line myself (as opposed to processed GIS line work). Even a very shallow simple curved line does the same thing, so it must be my construction of the brush thats wrong... but I'm not having any luck playing with the various settings.

I know there at least a couple of people on the forum who use this technique... I'd love it if they could give us a run down on their work flow for this.

[mika]

I know the question was about how to do this in illy but I had similar problem in CorelDraw and managed to solve it by simply creating the brush based on the lines only - no fill involved. While filled brush worked well with fairly smooth vectors, GIS based river data was to complex for it to work well. Removing the fill and simulating it by using two or more lines shaped in a triangle did the trick.

[David Medeiros]

So it looks like my issue is a function of how many anchor pints there are in the object I use to create my new brush. By using the "add anchor point" command a few times I can drastically increase the number of anchors allowing the new art brush to more closely follow my path. I'm still having some issue with the brush knocking itself out at the tightest bends but it looks a lot better now.

I'm certain there are cartographers on this forum who use this technique regularly, I would really love to get one of you to do a quick write up on your work flow for this effect.

Attached Files

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[razornole]

So it looks like my issue is a function of how many anchor pints there are in the object I use to create my new brush. By using the "add anchor point" command a few times I can drastically increase the number of anchors allowing the new art brush to more closely follow my path. I'm still having some issue with the brush knocking itself out at the tightest bends but it looks a lot better now.

I'm certain there are cartographers on this forum who use this technique regularly, I would really love to get one of you to do a quick write up on your work flow for this effect.

While you are waiting, have you tried the 'Improve Bezier and Lines' filter from the Swiss Cartography Institute before applying the brush?

kru

[EJHutzler]

SmoothLineWidth.aip generated 'taper' lines like rivers.
(Page 30 http://www.ika.ethz.ch/plugins/plg14_Dokum...hreibungen.pdf)
The Plugin You can use for beziers and linear segments.

ejhutzler