Planner: Add backgas breaks

If the corresponding checkbox is checked the planner does interrupt
pure O2 deco after 12min for 6min on cylinder 0.

To make this work for air I removed the gasmix_is_null logic.

I guess that makes the planner feature complete for the next release.

[Dirk Hohndel: trivial merge into latest master]

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

planner.c

@@ -721,6 +721,9 @@ void plan(struct diveplan *diveplan, char **cached_datap, bool add_deco, bool sh
 	int last_ascend_rate;
 	int best_first_ascend_cylinder;
 	struct gasmix gas;
+	int o2time = 0;
+	int breaktime = -1;
+	int breakcylinder;
 
 	set_gf(diveplan->gflow, diveplan->gfhigh, prefs.gf_low_at_maxdepth);
 	if (!diveplan->surface_pressure)
@@ -862,6 +865,31 @@ void plan(struct diveplan *diveplan, char **cached_datap, bool add_deco, bool sh
 						       DECOTIMESTEP, po2, &displayed_dive);
 			cache_deco_state(tissue_tolerance, &trial_cache);
 			clock += DECOTIMESTEP;
+			if (prefs.doo2breaks) {
+				if (get_o2(&displayed_dive.cylinder[current_cylinder].gasmix) == 1000) {
+					o2time += DECOTIMESTEP;
+					if (o2time >= 12 * 60) {
+						breaktime = 0;
+						breakcylinder = current_cylinder;
+						plan_add_segment(diveplan, clock - previous_point_time, depth, gas, po2, false);
+						previous_point_time = clock;
+						current_cylinder = 0;
+						gas = displayed_dive.cylinder[current_cylinder].gasmix;
+					}
+				} else {
+					if (breaktime >= 0) {
+						breaktime += DECOTIMESTEP;
+						if (breaktime >= 6 * 60) {
+							o2time = 0;
+							plan_add_segment(diveplan, clock - previous_point_time, depth, gas, po2, false);
+							previous_point_time = clock;
+							current_cylinder = breakcylinder;
+							gas = displayed_dive.cylinder[current_cylinder].gasmix;
+							breaktime = -1;
+						}
+					}
+				}
+			}
 			trial_depth = depth;
 		}
 		if (stopping) {

pref.h

@@ -61,6 +61,7 @@ struct preferences {
 	short proxy_auth;
 	char *proxy_user;
 	char *proxy_pass;
+	bool doo2breaks;
 };
 enum unit_system_values {
 	METRIC,

qt-ui/diveplanner.cpp

@@ -378,6 +378,7 @@ PlannerSettingsWidget::PlannerSettingsWidget(QWidget *parent, Qt::WindowFlags f)
 	ui.descRate->setValue(prefs.descrate / UNIT_FACTOR);
 	ui.bottompo2->setValue(prefs.bottompo2 / 1000.0);
 	ui.decopo2->setValue(prefs.decopo2 / 1000.0);
+	ui.backgasBreaks->setChecked(prefs.doo2breaks);
 
 
 	connect(ui.lastStop, SIGNAL(toggled(bool)), plannerModel, SLOT(setLastStop6m(bool)));
@@ -402,6 +403,7 @@ PlannerSettingsWidget::PlannerSettingsWidget(QWidget *parent, Qt::WindowFlags f)
 	connect(ui.decoStopSAC, SIGNAL(valueChanged(int)), this, SLOT(decoSacChanged(int)));
 	connect(ui.gfhigh, SIGNAL(valueChanged(int)), plannerModel, SLOT(setGFHigh(int)));
 	connect(ui.gflow, SIGNAL(valueChanged(int)), plannerModel, SLOT(setGFLow(int)));
+	connect(ui.backgasBreaks, SIGNAL(toggled(bool)), this, SLOT(setBackgasBreaks(bool)));
 
 	ui.bottomSAC->setValue(20);
 	ui.decoStopSAC->setValue(17);
@@ -475,6 +477,11 @@ void PlannerSettingsWidget::setDecoPo2(double po2)
 	prefs.decopo2 = (int) (po2 * 1000.0);
 }
 
+void PlannerSettingsWidget::setBackgasBreaks(bool dobreaks)
+{
+	prefs.doo2breaks = dobreaks;
+}
+
 
 void DivePlannerPointsModel::setPlanMode(Mode m)
 {

qt-ui/diveplanner.h

@@ -168,6 +168,7 @@ slots:
 	void setDescRate(int rate);
 	void setBottomPo2(double po2);
 	void setDecoPo2(double po2);
+	void setBackgasBreaks(bool dobreaks);
 
 private:
 	Ui::plannerSettingsWidget ui;

subsurfacestartup.c

@@ -39,7 +39,8 @@ struct preferences default_prefs = {
 	.ascratelast6m = 1000 / 60,
 	.descrate = 18000 / 60,
 	.bottompo2 = 1400,
-	.decopo2 = 1600
+	.decopo2 = 1600,
+	.doo2breaks = false
 };
 
 int run_survey;