CCR gas composition and gas pressure labels on dive profile: revisited

This patch cleans up code for achieving the above with respect to
CCR dives. The code is simplified and shortened. The display of
gas lables on the profile is made consistent with the cylinder
pressure closest to the graph and the gas composition above/below
the cylinder pressure. The patch significantly improves the
maintainability of this code.

Signed-off-by: willem ferguson <willemferguson@zoology.up.ac.za>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 10 insertions, 29 deletions

diff --git a/qt-ui/profile/diveprofileitem.cpp b/qt-ui/profile/diveprofileitem.cpp
index 3bc79832e..c14561638 100644
--- a/qt-ui/profile/diveprofileitem.cpp
+++ b/qt-ui/profile/diveprofileitem.cpp
@@ -682,8 +682,8 @@ void DiveGasPressureItem::modelDataChanged(const QModelIndex &topLeft, const QMo
 
 	bool offsets_initialised = false;
 	int o2cyl = -1, dilcyl = -1;
-	QFlags<Qt::AlignmentFlag> alignVar, align_dil = Qt::AlignBottom, align_o2 = Qt::AlignBottom;
-	double axisRange = (vAxis->maximum() - vAxis->minimum())/1000;
+	QFlags<Qt::AlignmentFlag> alignVar= Qt::AlignTop, align_dil = Qt::AlignBottom, align_o2 = Qt::AlignTop;
+	double axisRange = (vAxis->maximum() - vAxis->minimum())/1000;	// Convert axis pressure range to bar
 	double axisLog = log10(log10(axisRange));
 	for (int i = 0, count = dataModel->rowCount(); i < count; i++) {
 		entry = dataModel->data().entry + i;
@@ -691,23 +691,17 @@ void DiveGasPressureItem::modelDataChanged(const QModelIndex &topLeft, const QMo
 		if (displayed_dive.dc.divemode == CCR && displayed_dive.oxygen_cylinder_index >= 0)
 			o2mbar = GET_O2CYLINDER_PRESSURE(entry);
 
-		if (o2mbar) {
+		if (o2mbar) {	// If there is an o2mbar value then this is a CCR dive. Then do:
 			// The first time an o2 value is detected, see if the oxygen cyl pressure graph starts above or below the dil graph
 			if (!offsets_initialised) {	// Initialise the parameters for placing the text correctly near the graph line:
 				o2cyl = displayed_dive.oxygen_cylinder_index;
 				dilcyl = displayed_dive.diluent_cylinder_index;
 				if ((o2mbar > mbar)) {	// If above, write o2 start cyl pressure above graph and diluent pressure below graph:
-					print_y_offset[o2cyl][0] = -7 * axisLog; // y offset for oxygen gas lable (above)
-					print_y_offset[o2cyl][1] = -0.5;	 // y offset for oxygen start pressure value (above)
+					print_y_offset[o2cyl][0] = -7 * axisLog; // y offset for oxygen gas lable (above); pressure offsets=-0.5, already initialised
 					print_y_offset[dilcyl][0] = 5 * axisLog; // y offset for diluent gas lable (below)
-					print_y_offset[dilcyl][1] = 0;		 // y offset for diluent start pressure value (below)
-					align_dil = Qt::AlignBottom;
-					align_o2  = Qt::AlignTop;
-				} else {					// ... else write o2 start cyl pressure below graph:
-					print_y_offset[o2cyl][0]  = 5 * axisLog; // o2 lable & pressure below graph,
-					print_y_offset[o2cyl][1]  = 0;
-					print_y_offset[dilcyl][0] = -7 * axisLog;  // and diluent lable above graph.
-					print_y_offset[dilcyl][1] = -0.5;	// and diluent pressure above graph.
+				} else {				// ... else write o2 start cyl pressure below graph:
+					print_y_offset[o2cyl][0]  = 5 * axisLog; // o2 lable & pressure below graph; pressure offsets=-0.5, already initialised
+					print_y_offset[dilcyl][0] = -7.8 * axisLog;  // and diluent lable above graph.
 					align_dil = Qt::AlignTop;
 					align_o2  = Qt::AlignBottom;
 				}
@@ -722,9 +716,6 @@ void DiveGasPressureItem::modelDataChanged(const QModelIndex &topLeft, const QMo
 			last_pressure[displayed_dive.oxygen_cylinder_index] = o2mbar;
 			last_time[displayed_dive.oxygen_cylinder_index] = entry->sec;
 			alignVar = align_dil;
-		} else {
-			alignVar = Qt::AlignBottom;
-			align_dil = Qt::AlignTop;
 		}
 
 		if (!mbar)
@@ -733,29 +724,19 @@ void DiveGasPressureItem::modelDataChanged(const QModelIndex &topLeft, const QMo
 		if (cyl != entry->cylinderindex) {	// Pressure value near the left hand edge of the profile - other cylinders:
 			cyl = entry->cylinderindex;	// For each other cylinder, write the gas lable and pressure
 			if (!seen_cyl[cyl]) {
-				plotPressureValue(mbar, entry->sec, alignVar, print_y_offset[cyl][0]);
-				plotGasValue(mbar, entry->sec, displayed_dive.cylinder[cyl].gasmix, align_dil, print_y_offset[cyl][1]);
+				plotPressureValue(mbar, entry->sec, alignVar, print_y_offset[cyl][1]);
+				plotGasValue(mbar, entry->sec, displayed_dive.cylinder[cyl].gasmix, align_dil, print_y_offset[cyl][0]);
 				seen_cyl[cyl] = true;
 			}
 		}
 		last_pressure[cyl] = mbar;
 		last_time[cyl] = entry->sec;
 	}
-						// Now, for the cylinder pressure written near the right edge of the profile:
-	if ((o2cyl >= 0) && (dilcyl >= 0)) {	// At first, skip uninitialised values of o2cyl and dilcyl
-		if (last_pressure[o2cyl] > last_pressure[dilcyl]) { // If oxygen cyl pressure graph ends above diluent graph:
-			align_dil =  Qt::AlignTop;	// initialise to write diluent cyl end pressure underneath the graph
-			align_o2  =  Qt::AlignBottom;
-		} else {
-			align_dil =  Qt::AlignBottom;	// else initialise to write diluent cyl end pressure above the graph
-			align_o2  =  Qt::AlignTop;
-		}
-	}
 
 	for (cyl = 0; cyl < MAX_CYLINDERS; cyl++) {	// For each cylinder, on right hand side of profile, write cylinder pressure
 		alignVar = ((o2cyl >= 0) && (cyl == displayed_dive.oxygen_cylinder_index)) ? align_o2 : align_dil;
 		if (last_time[cyl]) {
-			plotPressureValue(last_pressure[cyl], last_time[cyl], (alignVar | Qt::AlignLeft), print_y_offset[cyl][0]);
+			plotPressureValue(last_pressure[cyl], last_time[cyl], (alignVar | Qt::AlignLeft), print_y_offset[cyl][1]);
 		}
 	}
 }