AW: Re: [compiz] [PATCH] minimize doesn't respect "no core instance" flag

[Danny Baumann]

Hi,

> We've done this before and the problem with this is that there might be
> conflicts with other plugins. What if some other plugin also wants to
> transform the core instance? Having plugins animate a separate instance
> of the window instead of the core instance gives us a well defined
> behavior in all situations. If plugins are animating the core instance,
> then you have an infinite number of possible states that the core
> instance could be in as it's defined by the state of all loaded plugins.
> 
> When writing a plugin, it's always a good idea to consider the case
> where two instances of the plugin is loaded. That's of course not
> something that has to be supported but if the behavior when having two
> instances loaded is well defined, you're off to a good start. 

Well, this approach has obvious problems, too: With the "only one core
instance" approach, the look of an animation could be pretty weird if
there were multiple plugins animating at the same time. However, with
the "one instance per animating plugin" approach, there would be
multiple instances of the same window with different animations, which
will look pretty weird as well ;-)

It may be a matter of personal preference, but I prefer the "only one
instance only" approach because it gives us the opportunity to hide
windows completely, which the second approach doesn't provide.
Additionally, I think the "look and feel" of this approach would look
less weird to the end user than with the "multiple instances" approach.

Also, I'm not completely sure what you mean by "possible states". I
mean, the transformation of a window isn't a real state machine which
needs state machine transitions where action 1 could influence if action
2 could be executed or not. In my opinion, plugins can act completely
sepearately on the window transformation and the only question is if the
result of the transformations look visually appealing or not. Maybe I am
missing something - if I do, please enlighten me :-)

Regards,

Danny