Inkscape Tiled Clones

Inkscape has this dialog hidden in Edit -> Clone -> Create Tiled Clones…:

It has been brought up on the Inkscape-devel list and I decided to have a closer look.

Inkscape defaults to shifting the clones by 100% width of the selected object for columns and 100% height for rows. So the parameters on the Shift page are actually about the deviation from that, but the interface doesn’t make that clear at all.

Shift and Scale only take %, but should allow absolute values with a unit of the user’s choice.

Rows, columns wouldn’t make sense for radial arrangements that should also be possible.

Width, height: it could be made clearer that this option will fill the specified area and in what directions (original defines top left).

Use saved size and position of the tile checkbox: what is the use case for this option?
The tool-tip shows that this needs a lot of explanation: “Pretend that the size and position of the tile are the same as the last time you tiled it (if any), instead of using the current size”.

The Exponent parameter on the Shift and Scale pages depends on the tool-tip to explain that it defines whether rows will be spaced evenly (1), converge (1).

Trace page: Well, non of my tests produced anything sensible or useful.

The Symmetry page only contains a pop-up list (what GTK+ erroneously calls a combo box) full of mysterious items:

These are the 17 wallpaper groups, all possible tilings with translational symmetry. I don’t think knowledge of these should be expected. At the very least, the term wallpaper groups should be mentioned. Even once you know what this is about, the descriptions might not help you much with recalling the patterns or with predicting the outcome based on the selected object.

The Wikipedia article includes diagrams, but I didn’t find them to help much. A page of Inkscape: Guide to a Vector Drawing Program is much better. There are 11 groups based on rectangles (2 of them can be parallelograms), 1 on right-angled rectangles (rectangles cut apart diagonally) and 5 on hexagon subdivisions.

Here’s an attempt at creating the most simple schematics, leaving out points of rotation and mirror axes to just depict orientation. The place taken by the selected object is darkened:

These could be added to the descriptions given now.