Fix the imperial cylinder size calculations in equipment handling

This makes us use the same linear calculations as we did in the Gtk
branch.  We don't take compressibility into account, since tank
manufacturers don't seem to either.  A Luxfer AL80 is 11.1 liters, and
with the standard (non-compressibility) calculations, 80 cuft of air at
3000 psi is 11.094 liter, so that is the right model to use.

Also, stop with the horrible "units in edited numbers" stuff.  It uses
up precious space, and doesn't look any better.  If the user asked for
cuft, give him cuft without making a big deal about it.

Oh, and if the working pressure doesn't exist, sizes are always in
liters.  That's what we did in the Gtk branch, that's what we do here.
Again, no reason to even bother stating units, it's not helping.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 22 insertions, 25 deletions

diff --git a/qt-ui/models.cpp b/qt-ui/models.cpp
index 489f91bb6..4ef8bc6ca 100644
--- a/qt-ui/models.cpp
+++ b/qt-ui/models.cpp
@@ -84,12 +84,16 @@ QVariant CylindersModel::data(const QModelIndex& index, int role) const
 			// we can't use get_volume_string because the idiotic imperial tank
 			// sizes take working pressure into account...
 			if (cyl->type.size.mliter) {
-				if (prefs.units.volume == prefs.units.CUFT) {
-					double cuft = ml_to_cuft(gas_volume(cyl, cyl->type.workingpressure));
-					ret = QString("%1cuft").arg(cuft, 0, 'f', 1);
+				double volume;
+				int mbar = cyl->type.workingpressure.mbar;
+
+				if (mbar && prefs.units.volume == prefs.units.CUFT) {
+					volume = ml_to_cuft(cyl->type.size.mliter);
+					volume *= bar_to_atm(mbar / 1000.0);
 				} else {
-					ret = QString("%1l").arg(cyl->type.size.mliter / 1000.0, 0, 'f', 1);
+					volume = cyl->type.size.mliter / 1000.0;
 				}
+				ret = QString("%1").arg(volume, 0, 'f', 1);
 			}
 			break;
 		case WORKINGPRESS:
@@ -164,28 +168,21 @@ bool CylindersModel::setData(const QModelIndex& index, const QVariant& value, in
 			if (value.toDouble() != 0.0) {
 				TankInfoModel *tanks = TankInfoModel::instance();
 				QModelIndexList matches = tanks->match(tanks->index(0,0), Qt::DisplayRole, cyl->type.description);
-				if (prefs.units.volume == prefs.units.CUFT) {
-					if (cyl->type.workingpressure.mbar == 0) {
-						// this is a hack as we can't store a wet size
-						// without working pressure in cuft mode
-						// so we assume it's an aluminum tank at 3000psi
-						cyl->type.workingpressure.mbar = psi_to_mbar(3000);
-						if (!matches.isEmpty())
-							tanks->setData(tanks->index(matches.first().row(), TankInfoModel::BAR), cyl->type.workingpressure.mbar / 1000.0);
-					}
-					if (cyl->type.size.mliter != wet_volume(value.toDouble(), cyl->type.workingpressure)) {
-						mark_divelist_changed(TRUE);
-						cyl->type.size.mliter = wet_volume(value.toDouble(), cyl->type.workingpressure);
-						if (!matches.isEmpty())
-							tanks->setData(tanks->index(matches.first().row(), TankInfoModel::ML), cyl->type.size.mliter);
-					}
+				int mbar = cyl->type.workingpressure.mbar;
+				int mliter;
+
+				if (mbar && prefs.units.volume == prefs.units.CUFT) {
+					double liters = cuft_to_l(value.toDouble());
+					liters /= bar_to_atm(mbar / 1000.0);
+					mliter = rint(liters * 1000);
 				} else {
-					if (cyl->type.size.mliter != value.toDouble() * 1000.0) {
-						mark_divelist_changed(TRUE);
-						cyl->type.size.mliter = value.toDouble() * 1000.0;
-						if (!matches.isEmpty())
-							tanks->setData(tanks->index(matches.first().row(), TankInfoModel::ML), cyl->type.size.mliter);
-					}
+					mliter = rint(value.toDouble() * 1000);
+				}
+				if (cyl->type.size.mliter != mliter) {
+					mark_divelist_changed(TRUE);
+					cyl->type.size.mliter = mliter;
+					if (!matches.isEmpty())
+						tanks->setData(tanks->index(matches.first().row(), TankInfoModel::ML), cyl->type.size.mliter);
 				}
 			}
 		}