diff --git a/core/divelist.cpp b/core/divelist.cpp
index d198800fc..35679cf61 100644
--- a/core/divelist.cpp
+++ b/core/divelist.cpp
@@ -96,8 +96,8 @@ std::unique_ptr<dive> dive_table::default_dive()
 	auto d = std::make_unique<dive>();
 	d->when = time(nullptr) + gettimezoneoffset() + 3600;
 	d->dcs[0].duration = 40_min;
-	d->dcs[0].maxdepth.mm = M_OR_FT(15, 45);
-	d->dcs[0].meandepth.mm = M_OR_FT(13, 39); // this creates a resonable looking safety stop
+	d->dcs[0].maxdepth = m_or_ft(15, 45);
+	d->dcs[0].meandepth = m_or_ft(13, 39); // this creates a resonable looking safety stop
 	make_manually_added_dive_dc(&d->dcs[0]);
 	fake_dc(&d->dcs[0]);
 	add_default_cylinder(d.get());
diff --git a/core/equipment.cpp b/core/equipment.cpp
index fff8c1fa2..a418e209f 100644
--- a/core/equipment.cpp
+++ b/core/equipment.cpp
@@ -314,7 +314,7 @@ void reset_cylinders(struct dive *dive, bool track_gas)
 
 	for (cylinder_t &cyl: dive->cylinders) {
 		if (cyl.depth.mm == 0) /* if the gas doesn't give a mod, calculate based on prefs */
-			cyl.depth = dive->gas_mod(cyl.gasmix, decopo2, M_OR_FT(3,10));
+			cyl.depth = dive->gas_mod(cyl.gasmix, decopo2, m_or_ft(3, 10).mm);
 		if (track_gas)
 			cyl.start.mbar = cyl.end.mbar = cyl.type.workingpressure.mbar;
 		cyl.gas_used = 0_l;
diff --git a/core/planner.cpp b/core/planner.cpp
index 69be37dbf..75bc11481 100644
--- a/core/planner.cpp
+++ b/core/planner.cpp
@@ -660,9 +660,9 @@ std::vector<decostop> plan(struct deco_state *ds, struct diveplan &diveplan, str
 	 * Remark: not reentrant, but the user probably won't change preferences while this is running.
 	 */
 	if (prefs.last_stop)
-		decostoplevels[1].mm = 0;
+		decostoplevels[1] = 0_m;
 	else
-		decostoplevels[1].mm = M_OR_FT(3,10);
+		decostoplevels[1] = m_or_ft(3, 10);
 
 	/* Let's start at the last 'sample', i.e. the last manually entered waypoint. */
 	const struct sample &sample = dc->samples.back();
@@ -1027,7 +1027,7 @@ std::vector<decostop> plan(struct deco_state *ds, struct diveplan &diveplan, str
 		 * otherwise odd things can happen, such as CVA causing the final ascent to start *later*
 		 * if the ascent rate is slower, which is completely nonsensical.
 		 * Assume final ascent takes 20s, which is the time taken to ascend at 9m/min from 3m */
-		ds->deco_time = clock - bottom_time - (M_OR_FT(3,10) * ( prefs.last_stop ? 2 : 1)) / last_ascend_rate + 20;
+		ds->deco_time = clock - bottom_time - (m_or_ft(3, 10).mm * ( prefs.last_stop ? 2 : 1)) / last_ascend_rate + 20;
 	} while (!is_final_plan && error == PLAN_OK);
 
 	plan_add_segment(diveplan, clock - previous_point_time, 0, current_cylinder, po2, false, divemode);
diff --git a/core/profile.cpp b/core/profile.cpp
index 7a85dd660..85c9366e7 100644
--- a/core/profile.cpp
+++ b/core/profile.cpp
@@ -764,12 +764,12 @@ static void calculate_ndl_tts(struct deco_state *ds, const struct dive *dive, st
 	const int ascent_s_per_deco_step = 1;
 	/* how long time steps in deco calculations? */
 	const int time_stepsize = 60;
-	const int deco_stepsize = M_OR_FT(3, 10);
+	const depth_t deco_stepsize = m_or_ft(3, 10);
 	/* at what depth is the current deco-step? */
 	depth_t ascent_depth { .mm = entry.depth };
 	int next_stop = round_up(deco_allowed_depth(
 					 tissue_tolerance_calc(ds, dive, dive->depth_to_bar(ascent_depth), in_planner),
-					 surface_pressure, dive, 1).mm, deco_stepsize);
+					 surface_pressure, dive, 1).mm, deco_stepsize.mm);
 	/* at what time should we give up and say that we got enuff NDL? */
 	/* If iterating through a dive, entry.tts_calc needs to be reset */
 	entry.tts_calc = 0;
@@ -802,14 +802,14 @@ static void calculate_ndl_tts(struct deco_state *ds, const struct dive *dive, st
 		add_segment(ds, dive->depth_to_bar(ascent_depth),
 			    gasmix, ascent_s_per_step, entry.o2pressure.mbar, divemode, prefs.decosac, in_planner);
 		next_stop = round_up(deco_allowed_depth(tissue_tolerance_calc(ds, dive, dive->depth_to_bar(ascent_depth), in_planner),
-							surface_pressure, dive, 1).mm, deco_stepsize);
+							surface_pressure, dive, 1).mm, deco_stepsize.mm);
 	}
 	ascent_depth.mm = next_stop;
 
 	/* And how long is the current deco-step? */
 	entry.stoptime_calc = 0;
 	entry.stopdepth_calc = next_stop;
-	next_stop -= deco_stepsize;
+	next_stop -= deco_stepsize.mm;
 
 	/* And how long is the total TTS */
 	while (next_stop >= 0) {
@@ -829,7 +829,7 @@ static void calculate_ndl_tts(struct deco_state *ds, const struct dive *dive, st
 				add_segment(ds, dive->depth_to_bar(ascent_depth),
 					    gasmix, ascent_s_per_deco_step, entry.o2pressure.mbar, divemode, prefs.decosac, in_planner);
 			ascent_depth.mm = next_stop;
-			next_stop -= deco_stepsize;
+			next_stop -= deco_stepsize.mm;
 		}
 	}
 }
diff --git a/core/units.cpp b/core/units.cpp
index 73e4b0c42..7d855840e 100644
--- a/core/units.cpp
+++ b/core/units.cpp
@@ -199,3 +199,8 @@ unsigned int get_distance(location_t loc1, location_t loc2)
 	return lrint(6371000 * c);
 }
 
+depth_t m_or_ft(int m, int ft)
+{
+	int mm = prefs.units.length == units::METERS ? m * 1000 : feet_to_mm(ft);
+	return depth_t::from_base(mm);
+}
diff --git a/core/units.h b/core/units.h
index dc32322d7..9636573aa 100644
--- a/core/units.h
+++ b/core/units.h
@@ -19,8 +19,6 @@
 #define HE_DENSITY 166
 #define ZERO_C_IN_MKELVIN 273150 // mKelvin
 
-#define M_OR_FT(_m, _f) ((prefs.units.length == units::METERS) ? ((_m) * 1000) : (feet_to_mm(_f)))
-
 /* Salinity is expressed in weight in grams per 10l */
 #define SEAWATER_SALINITY 10300
 #define EN13319_SALINITY 10200
@@ -193,6 +191,10 @@ static inline depth_t operator""_ft(unsigned long long ft)
 	return depth_t { .mm = static_cast<int32_t>(round(ft * 304.8)) };
 }
 
+// Return either the first argument in meters or the second argument in
+// feet, depending on use settings.
+depth_t m_or_ft(int m, int ft);
+
 struct pressure_t : public unit_base<pressure_t>
 {
 	int32_t mbar = 0; // pressure up to 2000 bar
diff --git a/profile-widget/profilewidget2.cpp b/profile-widget/profilewidget2.cpp
index 8094fc71b..c58018969 100644
--- a/profile-widget/profilewidget2.cpp
+++ b/profile-widget/profilewidget2.cpp
@@ -347,8 +347,8 @@ void ProfileWidget2::mouseDoubleClickEvent(QMouseEvent *event)
 			return;
 
 		int minutes = lrint(profileScene->timeAxis->valueAt(mappedPos) / 60);
-		int milimeters = lrint(profileScene->profileYAxis->valueAt(mappedPos) / M_OR_FT(1, 1)) * M_OR_FT(1, 1);
-		plannerModel->addStop(milimeters, minutes * 60);
+		depth_t depth { .mm = int_cast<int>(profileScene->profileYAxis->valueAt(mappedPos) / m_or_ft(1, 1).mm) * m_or_ft(1, 1).mm };
+		plannerModel->addStop(depth, minutes * 60);
 		if (currentState == EDIT)
 			emit stopAdded();
 	}
@@ -938,7 +938,7 @@ void ProfileWidget2::divePlannerHandlerMoved()
 		profileScene->timeAxis->setBounds(0.0, profileScene->timeAxis->maximum() * 1.02);
 
 	divedatapoint data = plannerModel->at(index);
-	data.depth.mm = lrint(profileScene->profileYAxis->valueAt(activeHandler->pos()) / M_OR_FT(1, 1)) * M_OR_FT(1, 1);
+	data.depth.mm = lrint(profileScene->profileYAxis->valueAt(activeHandler->pos()) / m_or_ft(1, 1).mm) * m_or_ft(1, 1).mm;
 	data.time = lrint(profileScene->timeAxis->valueAt(activeHandler->pos()));
 
 	plannerModel->editStop(index, data);
@@ -964,7 +964,7 @@ void ProfileWidget2::keyDownAction()
 	for (int row: handleIndices) {
 		divedatapoint dp = plannerModel->at(row);
 
-		dp.depth.mm += M_OR_FT(1, 5);
+		dp.depth += m_or_ft(1, 5);
 		plannerModel->editStop(row, dp);
 	}
 	if (currentState == EDIT && !handleIndices.empty())
@@ -983,7 +983,7 @@ void ProfileWidget2::keyUpAction()
 		if (dp.depth.mm <= 0)
 			continue;
 
-		dp.depth.mm -= M_OR_FT(1, 5);
+		dp.depth -= m_or_ft(1, 5);
 		plannerModel->editStop(row, dp);
 	}
 	if (currentState == EDIT && !handleIndices.empty())
diff --git a/qt-models/cylindermodel.cpp b/qt-models/cylindermodel.cpp
index 1d3513838..62e65d181 100644
--- a/qt-models/cylindermodel.cpp
+++ b/qt-models/cylindermodel.cpp
@@ -237,13 +237,13 @@ QVariant CylindersModel::data(const QModelIndex &index, int role) const
 			} else {
 				pressure_t modpO2;
 				modpO2.mbar = inPlanner ? prefs.bottompo2 : (int)(prefs.modpO2 * 1000.0);
-				return get_depth_string(d->gas_mod(cyl->gasmix, modpO2, M_OR_FT(1,1)), true);
+				return get_depth_string(d->gas_mod(cyl->gasmix, modpO2, m_or_ft(1, 1).mm), true);
 			}
 		case MND:
 			if (cyl->bestmix_he)
 				return QStringLiteral("*");
 			else
-				return get_depth_string(d->gas_mnd(cyl->gasmix, prefs.bestmixend, M_OR_FT(1,1)), true);
+				return get_depth_string(d->gas_mnd(cyl->gasmix, prefs.bestmixend, m_or_ft(1, 1).mm), true);
 			break;
 		case USE:
 			return gettextFromC::tr(cylinderuse_text[cyl->cylinder_use]);
@@ -414,7 +414,7 @@ bool CylindersModel::setData(const QModelIndex &index, const QVariant &value, in
 						prefs.o2consumption / prefs.decosac / prefs.pscr_ratio;
 			else
 				modpO2.mbar = prefs.decopo2;
-			cyl.depth = d->gas_mod(cyl.gasmix, modpO2, M_OR_FT(3, 10));
+			cyl.depth = d->gas_mod(cyl.gasmix, modpO2, m_or_ft(3, 10).mm);
 			cyl.bestmix_o2 = false;
 		}
 		type = Command::EditCylinderType::GASMIX;
@@ -443,7 +443,7 @@ bool CylindersModel::setData(const QModelIndex &index, const QVariant &value, in
 			}
 			pressure_t modpO2;
 			modpO2.mbar = prefs.decopo2;
-			cyl.depth = d->gas_mod(cyl.gasmix, modpO2, M_OR_FT(3, 10));
+			cyl.depth = d->gas_mod(cyl.gasmix, modpO2, m_or_ft(3, 10).mm);
 		}
 		type = Command::EditCylinderType::GASMIX;
 		break;
@@ -649,8 +649,8 @@ void CylindersModel::updateDecoDepths(pressure_t olddecopo2)
 	for (auto &cyl: d->cylinders) {
 		/* If the gas's deco MOD matches the old pO2, it will have been automatically calculated and should be updated.
 		 * If they don't match, we should leave the user entered depth as it is */
-		if (cyl.depth.mm == d->gas_mod(cyl.gasmix, olddecopo2, M_OR_FT(3, 10)).mm) {
-			cyl.depth = d->gas_mod(cyl.gasmix, decopo2, M_OR_FT(3, 10));
+		if (cyl.depth.mm == d->gas_mod(cyl.gasmix, olddecopo2, m_or_ft(3, 10).mm).mm) {
+			cyl.depth = d->gas_mod(cyl.gasmix, decopo2, m_or_ft(3, 10).mm);
 		}
 	}
 	emit dataChanged(createIndex(0, 0), createIndex(numRows - 1, COLUMNS - 1));
@@ -680,7 +680,7 @@ bool CylindersModel::updateBestMixes()
 				cyl.gasmix.he.permille = 1000 - get_o2(cyl.gasmix);
 			pressure_t modpO2;
 			modpO2.mbar = prefs.decopo2;
-			cyl.depth = d->gas_mod(cyl.gasmix, modpO2, M_OR_FT(3, 10));
+			cyl.depth = d->gas_mod(cyl.gasmix, modpO2, m_or_ft(3, 10).mm);
 			gasUpdated = true;
 		}
 		if (cyl.bestmix_he) {
diff --git a/qt-models/diveplannermodel.cpp b/qt-models/diveplannermodel.cpp
index 6824011b4..58d155bc5 100644
--- a/qt-models/diveplannermodel.cpp
+++ b/qt-models/diveplannermodel.cpp
@@ -90,12 +90,12 @@ void DivePlannerPointsModel::createSimpleDive(struct dive *dIn)
 	// If we're in drop_stone_mode, don't add a first point.
 	// It will be added implicitly.
 	if (!prefs.drop_stone_mode)
-		addStop(M_OR_FT(15, 45), 1 * 60, cylinderid, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
+		addStop(m_or_ft(15, 45), 1 * 60, cylinderid, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
 
-	addStop(M_OR_FT(15, 45), 20 * 60, 0, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
+	addStop(m_or_ft(15, 45), 20 * 60, 0, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
 	if (!isPlanner()) {
-		addStop(M_OR_FT(5, 15), 42 * 60, cylinderid, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
-		addStop(M_OR_FT(5, 15), 45 * 60, cylinderid, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
+		addStop(m_or_ft(5, 15), 42 * 60, cylinderid, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
+		addStop(m_or_ft(5, 15), 45 * 60, cylinderid, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
 	}
 	updateDiveProfile();
 }
@@ -173,7 +173,8 @@ void DivePlannerPointsModel::loadFromDive(dive *dIn, int dcNrIn)
 				if (newtime.seconds == lastrecordedtime.seconds)
 					newtime.seconds += 10;
 				divemode_t current_divemode = loop.at(newtime.seconds - 1);
-				addStop(depthsum / samplecount, newtime.seconds, cylinderid, last_sp.mbar, true, current_divemode);
+				depth_t depth { .mm = depthsum / samplecount };
+				addStop(depth, newtime.seconds, cylinderid, last_sp.mbar, true, current_divemode);
 				lastrecordedtime = newtime;
 			}
 			lasttime = newtime;
@@ -184,7 +185,7 @@ void DivePlannerPointsModel::loadFromDive(dive *dIn, int dcNrIn)
 	// make sure we get the last point right so the duration is correct
 	divemode_t current_divemode = loop.at(dc->duration.seconds);
 	if (!hasMarkedSamples && !dc->last_manual_time.seconds)
-		addStop(0, dc->duration.seconds,cylinderid, last_sp.mbar, true, current_divemode);
+		addStop(0_m, dc->duration.seconds,cylinderid, last_sp.mbar, true, current_divemode);
 	preserved_until = d->duration;
 
 	updateDiveProfile();
@@ -808,19 +809,19 @@ int DivePlannerPointsModel::lastEnteredPoint() const
 void DivePlannerPointsModel::addDefaultStop()
 {
 	removeDeco();
-	addStop(0, 0, -1, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
+	addStop(0_m, 0, -1, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
 }
 
-void DivePlannerPointsModel::addStop(int milimeters, int seconds)
+void DivePlannerPointsModel::addStop(depth_t depth, int seconds)
 {
 	removeDeco();
-	addStop(milimeters, seconds, -1, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
+	addStop(depth, seconds, -1, prefs.defaultsetpoint, true, UNDEF_COMP_TYPE);
 	updateDiveProfile();
 }
 
 // cylinderid_in == -1 means same gas as before.
 // divemode == UNDEF_COMP_TYPE means determine from previous point.
-int DivePlannerPointsModel::addStop(int milimeters, int seconds, int cylinderid_in, int ccpoint, bool entered, enum divemode_t divemode)
+int DivePlannerPointsModel::addStop(depth_t depth, int seconds, int cylinderid_in, int ccpoint, bool entered, enum divemode_t divemode)
 {
 	int cylinderid = 0;
 	bool usePrevious = false;
@@ -830,16 +831,16 @@ int DivePlannerPointsModel::addStop(int milimeters, int seconds, int cylinderid_
 		usePrevious = true;
 
 	int row = divepoints.count();
-	if (seconds == 0 && milimeters == 0) {
+	if (seconds == 0 && depth.mm == 0) {
 		if (row == 0) {
-			milimeters = M_OR_FT(5, 15); // 5m / 15ft
+			depth = m_or_ft(5, 15); // 5m / 15ft
 			seconds = 600;		     // 10 min
 			// Default to the first cylinder
 			cylinderid = 0;
 		} else {
 			/* this is only possible if the user clicked on the 'plus' sign on the DivePoints Table */
 			const divedatapoint t = divepoints.at(lastEnteredPoint());
-			milimeters = t.depth.mm;
+			depth = t.depth;
 			seconds = t.time + 600; // 10 minutes.
 			cylinderid = t.cylinderid;
 			ccpoint = t.setpoint;
@@ -881,7 +882,7 @@ int DivePlannerPointsModel::addStop(int milimeters, int seconds, int cylinderid_
 
 	// add the new stop
 	beginInsertRows(QModelIndex(), row, row);
-	divedatapoint point(seconds, milimeters, cylinderid, ccpoint, entered);
+	divedatapoint point(seconds, depth.mm, cylinderid, ccpoint, entered);
 	point.divemode = divemode;
 	divepoints.insert(divepoints.begin() + row, point);
 	endInsertRows();
diff --git a/qt-models/diveplannermodel.h b/qt-models/diveplannermodel.h
index 1dadfacc7..4358118e8 100644
--- a/qt-models/diveplannermodel.h
+++ b/qt-models/diveplannermodel.h
@@ -65,7 +65,7 @@ public:
 	struct deco_state final_deco_state;
 
 	void loadFromDive(dive *d, int dcNr);
-	void addStop(int millimeters, int seconds);
+	void addStop(depth_t depth, int seconds);
 	void cylindersChanged();
 public
 slots:
@@ -120,7 +120,7 @@ signals:
 private:
 	explicit DivePlannerPointsModel(QObject *parent = 0);
 	void clear();
-	int addStop(int millimeters, int seconds, int cylinderid_in, int ccpoint, bool entered, enum divemode_t);
+	int addStop(depth_t depth, int seconds, int cylinderid_in, int ccpoint, bool entered, enum divemode_t);
 	void removePoints(const std::vector<int> &rows);
 	void setupStartTime();
 	void setupCylinders();
diff --git a/tests/testplan.cpp b/tests/testplan.cpp
index 8a8b4a7e4..b6029345f 100644
--- a/tests/testplan.cpp
+++ b/tests/testplan.cpp
@@ -64,11 +64,11 @@ diveplan setupPlan()
 	cyl2->gasmix = oxygen;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(79, 260) * 60 / M_OR_FT(23, 75);
-	plan_add_segment(dp, 0, dive.gas_mod(ean36, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, M_OR_FT(3, 10)).mm, 2, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(79, 260), 0, 0, 1, OC);
-	plan_add_segment(dp, 30 * 60 - droptime, M_OR_FT(79, 260), 0, 0, 1, OC);
+	int droptime = m_or_ft(79, 260).mm * 60 / m_or_ft(23, 75).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(ean36, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, m_or_ft(3, 10).mm).mm, 2, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(79, 260).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 30 * 60 - droptime, m_or_ft(79, 260).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -99,11 +99,11 @@ diveplan setupPlanVpmb45m30mTx()
 	cyl2->gasmix = oxygen;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(45, 150) * 60 / M_OR_FT(23, 75);
-	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, M_OR_FT(3, 10)).mm, 2, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(45, 150), 0, 0, 1, OC);
-	plan_add_segment(dp, 30 * 60 - droptime, M_OR_FT(45, 150), 0, 0, 1, OC);
+	int droptime = m_or_ft(45, 150).mm * 60 / m_or_ft(23, 75).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, m_or_ft(3, 10).mm).mm, 2, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(45, 150).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 30 * 60 - droptime, m_or_ft(45, 150).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -134,11 +134,11 @@ diveplan setupPlanVpmb60m10mTx()
 	cyl2->gasmix = oxygen;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(60, 200) * 60 / M_OR_FT(23, 75);
-	plan_add_segment(dp, 0, dive.gas_mod(tx50_15, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, M_OR_FT(3, 10)).mm, 2, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
-	plan_add_segment(dp, 10 * 60 - droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
+	int droptime = m_or_ft(60, 200).mm * 60 / m_or_ft(23, 75).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(tx50_15, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, m_or_ft(3, 10).mm).mm, 2, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 10 * 60 - droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -158,9 +158,9 @@ diveplan setupPlanVpmb60m30minAir()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(60, 200) * 60 / M_OR_FT(99, 330);
-	plan_add_segment(dp, droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
-	plan_add_segment(dp, 30 * 60 - droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
+	int droptime = m_or_ft(60, 200).mm * 60 / m_or_ft(99, 330).mm;
+	plan_add_segment(dp, droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 30 * 60 - droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -187,10 +187,10 @@ diveplan setupPlanVpmb60m30minEan50()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(60, 200) * 60 / M_OR_FT(99, 330);
-	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
-	plan_add_segment(dp, 30 * 60 - droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
+	int droptime = m_or_ft(60, 200).mm * 60 / m_or_ft(99, 330).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 30 * 60 - droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -217,10 +217,10 @@ diveplan setupPlanVpmb60m30minTx()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(60, 200) * 60 / M_OR_FT(99, 330);
-	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
-	plan_add_segment(dp, 30 * 60 - droptime, M_OR_FT(60, 200), 0, 0, 1, OC);
+	int droptime = m_or_ft(60, 200).mm * 60 / m_or_ft(99, 330).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 30 * 60 - droptime, m_or_ft(60, 200).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -240,11 +240,11 @@ diveplan setupPlanVpmbMultiLevelAir()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(20, 66) * 60 / M_OR_FT(99, 330);
-	plan_add_segment(dp, droptime, M_OR_FT(20, 66), 0, 0, 1, OC);
-	plan_add_segment(dp, 10 * 60 - droptime, M_OR_FT(20, 66), 0, 0, 1, OC);
-	plan_add_segment(dp, 1 * 60, M_OR_FT(60, 200), 0, 0, 1, OC);
-	plan_add_segment(dp, 29 * 60, M_OR_FT(60, 200), 0, 0, 1, OC);
+	int droptime = m_or_ft(20, 66).mm * 60 / m_or_ft(99, 330).mm;
+	plan_add_segment(dp, droptime, m_or_ft(20, 66).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 10 * 60 - droptime, m_or_ft(20, 66).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 1 * 60, m_or_ft(60, 200).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 29 * 60, m_or_ft(60, 200).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -274,11 +274,11 @@ diveplan setupPlanVpmb100m60min()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(100, 330) * 60 / M_OR_FT(99, 330);
-	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, M_OR_FT(3, 10)).mm, 2, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(100, 330), 0, 0, 1, OC);
-	plan_add_segment(dp, 60 * 60 - droptime, M_OR_FT(100, 330), 0, 0, 1, OC);
+	int droptime = m_or_ft(100, 330).mm * 60 / m_or_ft(99, 330).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, m_or_ft(3, 10).mm).mm, 2, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(100, 330).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 60 * 60 - droptime, m_or_ft(100, 330).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -308,11 +308,11 @@ diveplan setupPlanVpmb100m10min()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(100, 330) * 60 / M_OR_FT(99, 330);
-	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, M_OR_FT(3, 10)).mm, 2, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(100, 330), 0, 0, 1, OC);
-	plan_add_segment(dp, 10 * 60 - droptime, M_OR_FT(100, 330), 0, 0, 1, OC);
+	int droptime = m_or_ft(100, 330).mm * 60 / m_or_ft(99, 330).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, m_or_ft(3, 10).mm).mm, 2, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(100, 330).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 10 * 60 - droptime, m_or_ft(100, 330).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -332,9 +332,9 @@ diveplan setupPlanVpmb30m20min()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(30, 100) * 60 / M_OR_FT(18, 60);
-	plan_add_segment(dp, droptime, M_OR_FT(30, 100), 0, 0, 1, OC);
-	plan_add_segment(dp, 20 * 60 - droptime, M_OR_FT(30, 100), 0, 0, 1, OC);
+	int droptime = m_or_ft(30, 100).mm * 60 / m_or_ft(18, 60).mm;
+	plan_add_segment(dp, droptime, m_or_ft(30, 100).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 20 * 60 - droptime, m_or_ft(30, 100).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -367,14 +367,14 @@ diveplan setupPlanVpmb100mTo70m30min()
 	dive.surface_pressure = 1_atm;
 	reset_cylinders(&dive, true);
 
-	int droptime = M_OR_FT(100, 330) * 60 / M_OR_FT(18, 60);
-	plan_add_segment(dp, 0, dive.gas_mod(tx21_35, po2, M_OR_FT(3, 10)).mm, 1, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, M_OR_FT(3, 10)).mm, 2, 0, 1, OC);
-	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, M_OR_FT(3, 10)).mm, 3, 0, 1, OC);
-	plan_add_segment(dp, droptime, M_OR_FT(100, 330), 0, 0, 1, OC);
-	plan_add_segment(dp, 20 * 60 - droptime, M_OR_FT(100, 330), 0, 0, 1, OC);
-	plan_add_segment(dp, 3 * 60, M_OR_FT(70, 230), 0, 0, 1, OC);
-	plan_add_segment(dp, (30 - 20 - 3) * 60, M_OR_FT(70, 230), 0, 0, 1, OC);
+	int droptime = m_or_ft(100, 330).mm * 60 / m_or_ft(18, 60).mm;
+	plan_add_segment(dp, 0, dive.gas_mod(tx21_35, po2, m_or_ft(3, 10).mm).mm, 1, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(ean50, po2, m_or_ft(3, 10).mm).mm, 2, 0, 1, OC);
+	plan_add_segment(dp, 0, dive.gas_mod(oxygen, po2, m_or_ft(3, 10).mm).mm, 3, 0, 1, OC);
+	plan_add_segment(dp, droptime, m_or_ft(100, 330).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 20 * 60 - droptime, m_or_ft(100, 330).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, 3 * 60, m_or_ft(70, 230).mm, 0, 0, 1, OC);
+	plan_add_segment(dp, (30 - 20 - 3) * 60, m_or_ft(70, 230).mm, 0, 0, 1, OC);
 	return dp;
 }
 
@@ -431,19 +431,19 @@ diveplan setupPlanCcr()
 	cylinder_t *cyl0 = dive.get_or_create_cylinder(0);
 	cylinder_t *cyl1 = dive.get_or_create_cylinder(1);
 	cyl0->gasmix = diluent;
-	cyl0->depth = dive.gas_mod(diluent, po2, M_OR_FT(3, 10));
+	cyl0->depth = dive.gas_mod(diluent, po2, m_or_ft(3, 10).mm);
 	cyl0->type.size = 3_l;
 	cyl0->type.workingpressure = 200_bar;
 	cyl0->cylinder_use = DILUENT;
 	cyl1->gasmix = ean53;
-	cyl1->depth = dive.gas_mod(ean53, po2, M_OR_FT(3, 10));
+	cyl1->depth = dive.gas_mod(ean53, po2, m_or_ft(3, 10).mm);
 	cyl2->gasmix = tx19_33;
-	cyl2->depth = dive.gas_mod(tx19_33, po2, M_OR_FT(3, 10));
+	cyl2->depth = dive.gas_mod(tx19_33, po2, m_or_ft(3, 10).mm);
 	reset_cylinders(&dive, true);
 
 	plan_add_segment(dp, 0, cyl1->depth.mm, 1, 0, false, OC);
 	plan_add_segment(dp, 0, cyl2->depth.mm, 2, 0, false, OC);
-	plan_add_segment(dp, 20 * 60, M_OR_FT(60, 197), 0, 1300, true, CCR);
+	plan_add_segment(dp, 20 * 60, m_or_ft(60, 197).mm, 0, 1300, true, CCR);
 
 	return dp;
 }