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dchall8
1,008 post(s)
#19-Jul-20 22:13

I created a 1 km buffer around a GPS point for a friend. The buffer is clearly not a circle but a multifaceted polygon. That's fine, but I would like to round that buffer polygon more. In M8 I used the Spline tool with a factor of 6. In M9 I tried using the Smooth transform, but it doesn't give a rounding effect. Instead it gives a squaring off effect. Instead of creating a Bezier or adding vertices between vertices, it removes vertices. Is there a way to do what I'm trying to do?

Here is the 1 km buffer around the center point.

Here is the imaged smoothed in M9 with a factor of 500.

Attachments:
1 KM circle around GPS pt .jpg
Circle smoothed factor 500.jpg

Dimitri


7,413 post(s)
#20-Jul-20 06:10

Create two curvilinear arcs, one on each side: that gives you a genuine circle, at least within the projection that you are using. There are examples in the Tracker: Measurements topic.

There are many workflows possible, depending on your skill set, muscle memory, preferences, etc, but one simple way is to create a buffer "circle" of the desired radius (copy the center point first, so you can paste it, thus getting both the buffer and retaining the original center point), and then Transform - Convert to Point to make points. The purpose of that is have points that are easy to snap to for exact measurements.

Next, with snapping on create a curvilinear line from one side of the buffer to the other, dragging the center handle of the circle arc to where it snaps to the edge of the circle. Create another curvilinear arc going in the other direction to the other side, and now you have a buffer.

Curves are rendered onscreen using straight segments, but when you print them to pdf there are more segments used for a smoother look. See the attached pdf for an example.

By the way, it's interesting to see the different sizes created by different print to PDF packages. Adobe print to PDF created a 223 KB file while Microsoft print to PDF created a PDF over 20 MB. (!)

Also, the "smooth" transform is really more of a "simplify" transform. See the Transform Templates - Drawings topic.

Attachments:
circle_adobe.pdf

dchall8
1,008 post(s)
#20-Jul-20 14:39

Thanks, that works. I watched the video on making curved lines, but that's been overcome a little bit by changes to the interface.

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