On Sat, May 12, 2007 at 12:52:14PM +0200, Rick van der Zwet wrote:

Hi all,

I have been trying to make a polor grid like picture, but it's a bit hard to do it by hand every time (circle->duplicate->make smaller->duplicate->make smaller->...)

...

As I understand correctly [1] Inkscape doesn't have a build-in function to accomplish this, so does anyone know a workaround to speed things up a bit?

I would probably use Tile Clones to achieve this. From the Tile Clones dialog, make sure you set the spacing between rows to -100% in the y direction. Pick the number of circles you want as the number of rows. Switch to the scale tab and set the scale factor: if you want each circle to be twice the diameter of the last, use a scale factor 2. There are lots of options there for making them exponential or jittering the position or scale should you want that. It may take a bit of trial and error the first time, but after that it will be easy.

The main shortcoming I can think of is that, IIRC, the stroke width will be scaled along with the circle, regardless of whether "scale stroke with object" is on or off. This is a side-effect of using clones. If it is a problem in your picture, you'll probably have to unlink all the clones from the original (I think the Tile Clones dialog has a button for it, otherwise just drag a box around them all and press alt+shift+d) and then with all the circles selected set the stroke width in the Stroke & Fill dialog: they will all get the width you set.

You can use a similar technique for radial lines if you want them, but rotating instead of scaling when you do Tile Clones.

Anyway, once you have finished your grid, select all the rings and radial lines and group them. Then you can copy and paste the whole grid as many times as you want it. If you use the same grid a lot, it might even be worth having an SVG file with just the grid in, then you can import it into each diagram you want it in.

HTH, Dan H