From 85d1e1d19929326e2324488850b54f7e80554af3 Mon Sep 17 00:00:00 2001
From: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
Date: Fri, 8 Oct 2021 21:28:32 +0200
Subject: [PATCH] profile: only plot visible range of tank info

This was a rather trivial change: simply pass in the first
and the last second to the plot function.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
---
 profile-widget/profilescene.cpp |  2 +-
 profile-widget/tankitem.cpp     | 35 ++++++++++++++++-----------------
 profile-widget/tankitem.h       |  2 +-
 3 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/profile-widget/profilescene.cpp b/profile-widget/profilescene.cpp
index 8a436effe..ef5541519 100644
--- a/profile-widget/profilescene.cpp
+++ b/profile-widget/profilescene.cpp
@@ -447,7 +447,7 @@ void ProfileScene::plotDive(const struct dive *dIn, int dcIn, DivePlannerPointsM
 		ocpo2GasItem->setVisible(false);
 	}
 #endif
-	tankItem->setData(&plotInfo, d);
+	tankItem->setData(d, firstSecond, lastSecond);
 
 	if (ppGraphsEnabled()) {
 		double max = prefs.pp_graphs.phe ? dataModel->pheMax() : -1;
diff --git a/profile-widget/tankitem.cpp b/profile-widget/tankitem.cpp
index ff4bd99d3..8377cbfdd 100644
--- a/profile-widget/tankitem.cpp
+++ b/profile-widget/tankitem.cpp
@@ -64,27 +64,19 @@ void TankItem::createBar(int startTime, int stopTime, struct gasmix gas)
 	label->setZValue(101);
 }
 
-void TankItem::setData(const struct plot_info *plotInfo, const struct dive *d)
+void TankItem::setData(const struct dive *d, int plotStartTime, int plotEndTime)
 {
-	if (!d)
-		return;
-
-	// If there is nothing to plot, quit early.
-	if (plotInfo->nr <= 0)
-		return;
-
-	// Find correct end of the dive plot for correct end of the tankbar.
-	const struct plot_data *last_entry = &plotInfo->entry[plotInfo->nr - 1];
-	int plotEndTime = last_entry->sec;
-
-	// We don't have enougth data to calculate things, quit.
-	if (plotEndTime < 0)
-		return;
-
 	// remove the old rectangles
 	qDeleteAll(rects);
 	rects.clear();
 
+	if (!d)
+		return;
+
+	// We don't have enougth data to calculate things, quit.
+	if (plotEndTime < 0 || plotEndTime <= plotStartTime)
+		return;
+
 	// Bail if there are no cylinders
 	if (d->cylinders.nr <= 0)
 		return;
@@ -96,15 +88,22 @@ void TankItem::setData(const struct plot_info *plotInfo, const struct dive *d)
 	// start with the first gasmix and at the start of the dive
 	int cyl = explicit_first_cylinder(d, dc);
 	struct gasmix gasmix = get_cylinder(d, cyl)->gasmix;
-	int startTime = 0;
+
+	// skip over all gas changes before the plotted range
+	const struct event *ev = get_next_event(dc->events, "gaschange");
+	while (ev && (int)ev->time.seconds <= plotStartTime)
+		ev = get_next_event(ev->next, "gaschange");
 
 	// work through all the gas changes and add the rectangle for each gas while it was used
-	const struct event *ev = get_next_event(dc->events, "gaschange");
+	int startTime = plotStartTime;
 	while (ev && (int)ev->time.seconds < plotEndTime) {
+		gasmix = get_gasmix_from_event(d, ev);
 		createBar(startTime, ev->time.seconds, gasmix);
 		startTime = ev->time.seconds;
 		gasmix = get_gasmix_from_event(d, ev);
 		ev = get_next_event(ev->next, "gaschange");
 	}
+	if (ev)
+		gasmix = get_gasmix_from_event(d, ev);
 	createBar(startTime, plotEndTime, gasmix);
 }
diff --git a/profile-widget/tankitem.h b/profile-widget/tankitem.h
index 66a942a8c..895c313f7 100644
--- a/profile-widget/tankitem.h
+++ b/profile-widget/tankitem.h
@@ -14,7 +14,7 @@ class TankItem : public QGraphicsRectItem
 {
 public:
 	explicit TankItem(const DiveCartesianAxis &axis, double dpr);
-	void setData(const struct plot_info *plotInfo, const struct dive *d);
+	void setData(const struct dive *d, int plotStartTime, int plotEndTime);
 	double height() const;
 
 private: