[RFC PATCH] Tweak cylinder equipment tooltips

[Dirk Hohndel]

I'd love to hear others comment on this. I'm in the middle of doing the 
4.6 release so I'm a bit busy right now (sources are tagged and pushed,
first binaries are up and I'm in the process of testing them - next come
the edits to the website)

/D

> On Jan 15, 2017, at 4:07 PM, Linus Torvalds <torvalds at linux-foundation.org> wrote:
> 
> 
> While playing around with the current subsurface, I realized that while we 
> give the gas volume and Z factor for the beginning/end pressures in the 
> newly added tooltips, there is no way to actually see that same 
> information for the working pressure.
> 
> So if you have filled in cylinder type information, but don't have any 
> actual gas usage information, there will be no cylinder tooltips at all. 
> But you might still want to know what the actual volume for a particular 
> cylinder is, and what the Z value for that working pressure is.
> 
> So this tweaks the tool-tips a bit.
> 
> When mousing over the pressure fields (ie "working pressure", "start" and 
> "end"), it now always gives the cylinder gas volume and Z factor for that 
> pressure, so for example on an AL72 that has a working pressure of 3000 
> psi and that contains air the tooltip will say:
> 
>   69 cuft, Z=1.040
> 
> when you mouse over the working pressure field (that's obviously with 
> imperial units, in metric you'll see liters of gas).
> 
> When mousing over the type/size field, it gives the used gas amounts, ie 
> something like this:
> 
>   37 cuft (82 cuft -> 45 cuft)
> 
> but if the cylinder doesn't have starting/ending pressures (and thus no 
> used gas information), this patch will make subsurface show the working 
> pressure data instead, so that you at least get something.
> 
> This all seems more useful than what my first version gave.
> 
> NOTE! This makes commit adaeb506b7a1 ("Show both the nominal and "real" 
> size for an imperial cylinder") kind of pointless. You now see the real 
> size in the tooltip when you mouse over the size, and now it actually 
> works both for imperial and metric people, so the tooltip is in many ways 
> the better model.
> 
> Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
> ---
> 
> This has an RFC because this is all obviously a subjective. Very few 
> people care about the compressibility factor, and realistically the main 
> reason to show it is to explain when people get confused.
> 
> Also, arguably, with this patch we really could just revert that now less 
> useful commit adaeb506b7a1. Again, it's a matter of taste. The tooltip 
> shows the same real gas volume information, and now also works for metric 
> cylinders. But the tooltip obviously needs that mouse-over. 
> 
> So which is better? Both? A matter of taste, I suspect.
> 
> But I signed off on the patch, because while I think this is a RFC and 
> might be good to have people opine on it, I also think the patch is 
> perfectly fine to just apply.
> 
> qt-models/cylindermodel.cpp | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/qt-models/cylindermodel.cpp b/qt-models/cylindermodel.cpp
> index c2c94f76..530ea635 100644
> --- a/qt-models/cylindermodel.cpp
> +++ b/qt-models/cylindermodel.cpp
> @@ -63,6 +63,8 @@ static QString gas_volume_string(int ml, const char *tail)
> 	return QString("%1 %2 %3").arg(vol, 0, 'f', decimals).arg(unit).arg(tail);
> }
> 
> +static QVariant gas_wp_tooltip(cylinder_t *cyl);
> +
> static QVariant gas_usage_tooltip(cylinder_t *cyl)
> {
> 	pressure_t startp = cyl->start.mbar ? cyl->start : cyl->sample_start;
> @@ -75,7 +77,7 @@ static QVariant gas_usage_tooltip(cylinder_t *cyl)
> 	used = (end && start > end) ? start - end : 0;
> 
> 	if (!used)
> -		return QVariant();
> +		return gas_wp_tooltip(cyl);
> 
> 	return gas_volume_string(used, "(") +
> 		gas_volume_string(start, " -> ") +
> @@ -94,6 +96,11 @@ static QVariant gas_volume_tooltip(cylinder_t *cyl, pressure_t p)
> 	return gas_volume_string(vol, "(Z=") + QString("%1)").arg(Z, 0, 'f', 3);
> }
> 
> +static QVariant gas_wp_tooltip(cylinder_t *cyl)
> +{
> +	return gas_volume_tooltip(cyl, cyl->type.workingpressure);
> +}
> +
> static QVariant gas_start_tooltip(cylinder_t *cyl)
> {
> 	return gas_volume_tooltip(cyl, cyl->start.mbar ? cyl->start : cyl->sample_start);
> @@ -228,9 +235,11 @@ QVariant CylindersModel::data(const QModelIndex &index, int role) const
> 		case REMOVE:
> 			ret = tr("Clicking here will remove this cylinder.");
> 			break;
> +		case TYPE:
> 		case SIZE:
> -		case WORKINGPRESS:
> 			return gas_usage_tooltip(cyl);
> +		case WORKINGPRESS:
> +			return gas_wp_tooltip(cyl);
> 		case START:
> 			return gas_start_tooltip(cyl);
> 		case END: