[MPlayer-dev-eng] [PATCH] GUI: Activate potmeter

[Hans-Dieter Kosch]

Ingo Brückl wrote:
> Hans-Dieter Kosch wrote on Wed, 19 Feb 2014 00:36:59 +0100:
> 
>> Ingo Brückl wrote:
>>> Hans-Dieter Kosch wrote on Sun, 16 Feb 2014 23:04:35 +0100:
>>>
>>>> The 'pressed' state of a 'potmeter' item is not initialised.
>>> Agreed.
>>>
>>>> By default it's 0 ('btnDisabled'), and the item is inactive.
>>> A potmeter doesn't have a btnDisabled state. Actually,
>>> the pressed state of a potmeter is irrelevant, because
>>> they cannot be pressed.
>>>
>> Cf. gui/skin/skin.c: line 619: in function item_hpotmeter():
>>      item->pressed   = btnReleased;
> 
> I know, but you can't compare to a hpotmeter. A hpotmeter has a button, a
> potmeter doesn't.

Ok, so far. But the form of a potmeter - horizontal, vertical or round - 
shouldn't have influence on its operation, should it? Can the round knob image 
of a pot not also be formally regarded as a button?

The point of confusion seems to me, that a pot basically can't have a 'pressed' 
state like a button, but this struct element is tri-state and the third value 
'btnDisabled' is used to disable a button, however it also affects a 
[hv]*potmeter (as said in the quote below).

Perhaps, it would be nice to have another element 'enabled' for clarity, but it 
would entail changes in several files.

>> The 'item->pressed' is used in gui/ui/main.c, line 102:
>>      if ( ( guiApp.mainItems[i].pressed != btnDisabled )&&
>> to determine if an object under the mouse is enabled. If it's
>> 'btnDisabled', then the object is ignored and the window is moved instead
>> of shifting the pot when the mouse is pressed and dragged.
> 
> Ok. So you want a potmeter to be shiftable by the mouse?

That would be intuitive from user's perspective, just like other elements on the 
skin can be controlled by the mouse.

> Did you notice that you already can do so with the Blue skin you were
> referring to while a video is playing? (So where do you miss mouse
> shiftability?)

Hmm, I can't reproduce. Even while playing a video, the window moves instead of 
the volume pot rotating when pressing and dragging the mouse over the pot (it's 
clearly the 'btnDisabled' state).

> (Admittedly, not all potmeters act this way. Would it be an alternative
> solution to adjust their behaviour to a movie position potmeter?)
> 
> Please keep in mind that (currently) potmeters aren't designed for user
> action. (Don't blame me, I did not invent them.)

Then, they'd make no sense appearing on the skin (no worry, I don't blame). But 
it could be easily fixed by this simple patch and all would be fine (besides the 
aforementioned coding pressed<->enabled); the other [hv]potmeters are already ok.

BTW. If you could decide to make it mouse-controllable by this patch or similar, 
then my second patch sent "Implement a true rotary potmeter" would yield a 
really beautyful pot like seen on other players...

Hans-Dieter