Am I missing something about why this is hard to do, or has it just never been a priority to provide "record to script" capability?

If my understanding is correct, the UNDO history does not record the actions you take, merely the result of those actions (by saving the portions of the image that were modified. The difficulty of providing a "record to script" functionality (AKA macro recorder) is that you would have to maintain a record of the specific actions taken (otherwise your recorded script would not work on a different image).

A macro recorder would basically have to be a different implementation than the UNDO history. I imagine certain simple actions (such as changing the opacity of a layer, select->none, etc) are already recorded in the UNDO history as "actions" and you might examine how those are handled if you are interested in implementing a macro recorder.

-------- "It is amazing what you can accomplish if you do not care who gets the credit." -- Harry S. Truman

Saul Goode wrote:

Am I missing something about why this is hard to do, or has it just never been a priority to provide "record to script" capability?

A macro recorder would basically have to be a different implementation than the UNDO history. I imagine certain simple actions (such as changing the opacity of a layer, select->none, etc) are already recorded in the UNDO history as "actions" and you might examine how those are handled if you are interested in implementing a macro recorder.

There is an enhancement request about a script/macro recoder with several good entries describing possible approaches and the respective problems:

http://bugzilla.gnome.org/show_bug.cgi?id=51937

HTH, Michael

On a related note to this thread, I was wondering if there was any way to have a script "perform" an Undo or to go back a few steps in the Undo history.

I have a script which chops a layer up into multiple pieces and the result is a layer that is centered relative to the original layer. In many situations, it would be desirable to have the generated layer aligned to the corners of the original layer. I had considered performing the additional alignment steps and then the user could perform UNDOs until he achieved the alignment he desired, but this would make it very tedious (and unintuitive) to perform an actual UNDO.

However, if I could perform the four alignments in the script and subsequently set the UNDO history back to the "centered" result, then the user could perform REDOs to attain his alignment while retaining the intuitive, one-step UNDO (or alternately, just continue with his editing).

I am unaware of any PDB function that would permit and would be interested in any input as to how this might be accomplished -- including which code in the core I might avail if I were to create such a PDB function.

--------
"It is amazing what you can accomplish if you do not care who gets the credit." -- Harry S. Truman

Hi,

On Wed, 2006-10-04 at 18:07 -0700, Saul Goode wrote:

I am unaware of any PDB function that would permit and would be interested in any input as to how this might be accomplished -- including which code in the core I might avail if I were to create such a PDB function.

The undo functionality is intentionally not exported to the PDB because it would be too easy for scripts and plug-ins to mess with the fragile internals of it then. What you described as a possible use case seems to be a very special case and I expect that anyone but the script author himself would only find it confusing.

Sven