[Bf-committers] Handling of user data.

[Ryan Inch]

Hi Julian,

 > The more dialog prompts we use in Blender, the more we make users get 
into the habit of just “clicking them away”, even in the wrong moments.

As far as I'm concerned, the only dialog prompt would still be at quit.  
Yes, the habitual dialog clicking is a well recognized design issue with 
well recognized solutions, what comes to my mind is using specific user 
actions as opposed to generic OK/Cancel, being specific about what is 
happening (so perhaps it would be better to incorporate the data manager 
into the prompt, rather than just listing what types of data would be 
discarded), and not overusing them[1].  However, the articles you list 
seem to address a slightly different issue than we have here.  The first 
one suggests to avoid them when you could implement a recovery via undo, 
however closing the program is not generally undo-able and even if you 
do save the unused data into quit.blend for a persistent session/session 
recovery, it still wouldn't help if you open a save.  The second article 
seems to actually be in favor of well designed confirmation dialogs and 
a well designed UI in general, and of course that's what we all strive 
for, and well designed confirmation dialogs are a part of that (see link[1])

 > The dialog box design also doesn’t cover the case of auto-save: Would 
we just always keep unused data in these?

For the case of auto-save, yes, I would just always keep unused data 
there because it is a temporary file that is only used in session 
recovery and unlikely to be shared (once loaded from the auto-save the 
unused data would not be saved to a regular blend file).

 > Honestly, this feels like one of the cases where dialog boxes are 
just lazy design. We need a proper design to manage unused data in Blender.

Honestly, I disagree that using a dialog box to address the issue is 
lazy design.  We have a well designed, base system, the problem being 
that it isn't common, people don't know about it, and it needs some 
guard rails.  Prompting on quit, especially if the prompt is 
non-standard will enlighten people to the fact that they're dealing with 
a different system than they're used to and provide a guard rail.

 > There are some ideas for this.

Pretty much all of the proposed ideas in T61209, except for the ones 
like Mike Drake's proposal that start off with a confirmation dialog, 
seem to revolve around removing the garbage collection system, but if 
there are some that don't I would be interested to read them.

 > So we don’t have to rewrite things really, but develop a new 
data-block management UI and tools.

Further management tools are definitely welcome, but the current system 
of purging unused data on quit is very useful and a requirement for high 
level workflows where you are working with blend files from outside, 
non-controllable sources[1].

Ryan Inch (Imaginer)

[1] https://www.nngroup.com/articles/confirmation-dialog/
[2] 
https://devtalk.blender.org/t/blender-deleted-my-un-assigned-materials-how-is-that-a-feature-fake-user/22715/55