Replicating a path

[Ottia Tuota]

Thanks to all who tried the plugin.

Here is a new plugin, "Replicate path by affine mapping". The idea is that when you take a path and apply the tools Move, Scalse, Rotate, Shear, Flip to it, then the plugin enables you to do the same action repeatedly in one step, producing a succession of paths. Some quickly made miscellanous examples of what the plugin does:

   

The plugin is here:

http://kmarkku.arkku.net/Path_replicate_...aster.html

Unzip the .zip file and place the one file it contains (replicate_path_by_affine_mapping.py) in your user's plug-ins folder. Then (re)start Gimp. The plugin is in the menu here:

Tools > Replicate > Replicate path by an affine mapping.

I explain the plugin now. But do not expect too much of it. It is rather limited and often what it produces is not what you were trying to get.

The plugin is used as follows. As input you give two paths; I call them "the Original path" and "the Seed".

1. The Original path is any path you have made.
   
2. The Seed you construct: (1) Take a copy of the Original path. (2) To the copy apply any of the tools Move, Scale, Rotate, Shear, Flip, either one of them or several in succession. (This means that you are applying some affine transformation.)
   
3. Then you call the plugin: right-click the Original path and navigate to the plugin, and in the GUI choose the Seed path.
   

Example

   

1. The Original path is created.
   
2. The Seed is created from a copy, in this picture with tools Move, Rotate, Scale.
   
3. The plugin is called with the proper paths.
   

The plugin works by examining the two input paths, recognizing the applied transformation to its best ability, and then applying the transformation repeatedly, producing a succession of new paths. Or, to borrow notation from mathematics, let

P = the Original path
F = the affine transformation (the tools Move,...).

Then Seed = F(P), and what the plugin creates are paths F(F(P)), F(F(F(P))), F(F(F(F(P)))), ...

As default the plugin merges all output paths together but it allows you to have them as separate paths.

A word of caution: It may happen that the transformation F cannot be determined uniquely from the Original path and the Seed. Then the plugin just chooses one from a small number of possibilities, and it may not be what you wanted. The remedy is to put an additional anchor somewhere in the Original path to help the plugin to make the right decision. (And the Seed must be constructed after adding the anchor.)

Finally, some playings, together with Path to selection and Bucket fill or Gradient. Sorry if these hurt your eyes, I don't have the same skills as some others.