History vs layers

[Bill S]

I know that I can figure this out by a lot of testing, but I thought I would ask here and see what I find?

I see that Affinity Photo has both History and Layers. I see how each can be put to good use. How does "Save History with Document" affect layers and how does it affect History? Do both of these apply to saving to .afphoto document files and to exporting to JPEG? Do layers get exported to JPEG?

I hope my questions make sense. I am obviously a newbie, but I really like the software. Thanks.

[gdenby]

The history keeps a record of every transformation/operation for the document. Before save, it allows one to shuttle back and forth between operations, doing as many levels of undo and redo as are set in preferences. If one wants to send a document down a different path, saving w. history will create a version. Another version w. a different name, say "Attempt 2" can have a history that is different from the point where the operations changed.

This really has nothing to do w. layers other than a record of when they were made in the process, and how they were re-arranged, etc.  But the file w. the history can be MUCH larger than the one w/o history. If one saves w/o history, the file will reopen as it was at the point of saving, and no undue list is available. Layers will be as they were at the save.

Files can be exported to several formats, .jpeg being one. Any number of layers can be included in the export slice. The export appears to me to be a grab of the screen saved in whatever format chosen. 

[Alfred]

Welcome to the Serif Affinity Forums, Bill.

The History list is a list of your editing steps. Normally the History is cleared on closing a document, but when the ‘Save History with Document’ option is switched on you retain access to those steps in a new session.

Layers determine the structure of the document. At its simplest level, you can think of the background layer as being like a sheet of paper or card, with additional layers sitting on top like acetate sheets, allowing the content of lower layers to show through the transparent areas.

JPEG is a ‘flat’ format which doesn’t support layers or transparency.

[toltec]

It is perhaps worth pointing out that one drawback of the ‘Save History with Document’ option, is that the file sizes will be larger on your disc. Sometimes considerably so,.

It is also worth mentioning Snapshots as they are very useful when working with history.

Snapshots save the current state of your document, complete with all layers and edits. Photo creates a snapshot (called 'Background'), when you load a document but you can create them at any time. They are good for experimenting, because by creating snapshots as you work, it is possible to make changes, create a snapshot, make more changes, create another snapshot and so on. Then you can then move between the snapshots at will, which is effectively like having different documents, but all inside one Photo document. You can't do that with history, because if you go back and make a change, you can't move forwards again because you have created a new 'timeline'.

It is also easy to create a new independent document from any one of the snapshots. 

Make a Snapshot by going Document > Add Snapshot and giving it a name. Go to any snapshot by going Document > Restore Snapshot and selecting the one you want.

Four Snapshots including the default 'Background' that Photo created as the document was loaded.

 

There is a dedicated Studio panel, View > Studio > Snapshots where you can delete them  or create a separate document from one.  

Snapshots are always saved inside the .afphoto file, whether  the ‘Save History with Document’ option is on or not. They are not saved in JPEGs etc.

[toltec]

6 hours ago, gdenby said:

. If one wants to send a document down a different path, saving w. history will create a version. Another version w. a different name, say "Attempt 2" can have a history that is different from the point where the operations changed.

Might you be confusing  the ‘Save History with Document’ option with 'Snapshots' ?