[mythtv] V2Capture::AddCardInput

Paul Harrison mythtv at mythqml.net
Tue Jul 5 18:00:37 UTC 2022

On 05/07/2022 18:01, David Engel wrote:

> On Tue, Jul 05, 2022 at 09:57:36AM -0600, John P Poet wrote:
>> On Tue, Jul 5, 2022 at 9:46 AM David Engel <david at istwok.net> wrote:
>>> On Tue, Jul 05, 2022 at 08:28:43AM -0600, John P Poet wrote:
>>>> On Tue, Jul 5, 2022, 12:33 AM Klaas de Waal <klaas.de.waal at gmail.com>
>>> wrote:
>>>>> On Tue, 5 Jul 2022 at 05:13, John P Poet <jppoet at gmail.com> wrote:
>>>>>> On Mon, Jul 4, 2022 at 8:30 PM David Engel <david at istwok.net> wrote:
>>>>>>> On Mon, Jul 04, 2022 at 08:03:45PM -0600, John P Poet wrote:
>>>>>>>> Hi all,
>>>>>>>> I don't think the call to CardUtil::IsUniqueDisplayName() should be
>>>>>>> fatal
>>>>>>>> in V2Capture::AddCardInput. *Only the last two characters* of the
>>>>>>>> DisplayName are considered to determine if it is unique. That
>>> unfairly
>>>>>>>> penalizes users who use a theme which can display more than two
>>>>>>> characters.
>>>>>>>> Thoughts?
>>>>>>> The last two characters of the short, display name can be and is used
>>>>>>> in themes.  Without enforcing this uniqueness requirement, themes
>>> that
>>>>>>> use the short, dispaly name will present ambiguous inputs.
>>>>>>> David
>>>>>> It should be up to the user to choose Display Names which work with
>>> the
>>>>>> theme they have chosen. Why penalize some users just to protect other
>>> users
>>>>>> from making a poor choice?
>>>>>> John
>>>>>> As I understand it, it is only a presentation string so it does not
>>>>> matter for correct operation.
>>>>> Consider using a 4-tuner HDHomeRun box. It is not really important
>>> which
>>>>> of the four tuners are used so a string like "HC" (short for HDHomerun
>>> You are correct that the physical tuner doesn't matter.  However, if
>>> you care about scheduling or especially, having to support scheduling
>>> issues, the logical tuner very much matters.
>>>>> Cable) could then be used for all four input connections.
>>>>> So I suggest doing it the same as in mythtv-setup; generate a default
>>> that
>>>>> is unique, e.g. "Input 12", but leave the decision to the user.
>>> It defaults to "Input XX", or at leat it used to.
>>>> Let's move CardUtil::IsUniqueDisplayName() to its own services API call.
>>>> Then the application can use it to warn the user of the consequences of
>>>> their choice.
>>> I strongly disagree.  Perhaps you never noticed, but the short,
>>> display name is used in multiple places like the System Status screen
>>> and the Change Input menu in live TV.  The intent was to replace input
>>> number with the [unique] short, display name in every user-facing
>>> location.  The reason for that was to more gracefully handle the
>>> proliferation of inpuss and increasingly, meaningless numbers.  In my
>>> case, I don't even know nor care what my input numbers are anymore.
>>> As for the length of the unique part, I think 2 characters is enough.
>>> However, as I stated in my private email, 3 could probably work if
>>> theme designers agree.
>>> David
>> David, I generally agree with you on most things, but not this. At least
>> not completely. I agree about the part of input numbers being meaningless.
>> I disagree that we should punish users of *some* themes just because *other*
>> themes went with the "short" name instead of the long one.
>> You are right that I never noticed the short name being used in those
>> places -- because with the Steppes theme, the short name is *not used
>> anywhere*.
> I wouldn't call requiring 2 or 3 characters to be unique "punishing".
> Is it really that hard?  I also think that's much better than risking
> the intentional confussion of users just because they happen to change
> themes.
> Look, display name must be unique in some way.  I see that as a given.
> The question then becomes how to also make it unique when it's used in
> a condensed format.  When I added the feature, I chose to use the last
> two characters.  It was much simpler than adding yet another name and
> it was easy code-wise, wasn't onerous for the user and was also the
> most likely place a user would distinguish between two or more of the
> same type of input -- Red 1/Red 2, Black 5/Black 6, etc.
> If you've got a another suggestion of how to take a unique, display
> name and condense it down to 2/3 characters that are also unique, then
> let's hear it.  I'm not wedded to the idea of using the last 2
> characters.  I'll happily change my input names if you have another
> way of maitaining uniqueness of both long and short names.
> David

To be honest I don't really care but I will say that as one of the dev's 
that persuaded Isaac many many years ago that being able to name the 
tuners was a good idea for identification purposes at no point did we 
ever say they should be 2 characters long!

It sounds to me like at some point someone decided it would be a good 
idea to use that name as an identifier in place of some 2 character 
number or cardid?  in the UI and didn't take into account the name can 
be anything. It was always meant to be a meaningful name not some 
cryptic 2 character id. It's just one of those things that always seems 
to happen in MythTV were over time things get added or changed but not 
necessarily in a sensible way.

Come back Isaac we may not have always agreed with him but at least we 
had a direction to follow and in the end progress was always made.  I 
miss those exciting times when you could go to bed one day and the next 
morning there would be a load of new features added over night and often 
a new release to play with :)

Paul H.

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