Calculate dive maxima/minima independent of dive computer

This splits the dive time, depth, pressure and temperature maxima and
minima setup from the per-dive-computer "create_plot_info()" function
into one setup function that walks _all_ the dive computers, so that we
have a global maxima and minima.

That way the graph scaling we set up will now fit the data from all dive
computers rather than just the particular one we are plotting.  So if
you switch back-and-forth between computers, the scale (which is defined
by the extremes) remains the same.

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

1 files changed, 77 insertions, 38 deletions

diff --git a/profile.c b/profile.c
index f8b4bd168..047767ebd 100644
--- a/profile.c
+++ b/profile.c
@@ -1091,7 +1091,7 @@ static int setup_temperature_limits(struct graphics_context *gc, struct plot_inf
 	else
 		gc->bottomy = mintemp - delta / 3;
 
-	pi->endtempcoord = SCALEY(gc, pi->endtemp);
+	pi->endtempcoord = SCALEY(gc, pi->mintemp);
 	return maxtemp > mintemp;
 }
 
@@ -1186,7 +1186,7 @@ static int get_cylinder_pressure_range(struct graphics_context *gc, struct plot_
 	if (!pi->maxpressure)
 		return FALSE;
 
-	while (pi->endtempcoord <= SCALEY(gc, pi->endpressure - (gc->topy) * 0.1))
+	while (pi->endtempcoord <= SCALEY(gc, pi->minpressure - (gc->topy) * 0.1))
 		gc->bottomy -=  gc->topy * 0.1;
 
 	return TRUE;
@@ -1424,27 +1424,6 @@ static struct plot_info *analyze_plot_info(struct plot_info *pi)
 	int i;
 	int nr = pi->nr;
 
-	/* Do pressure min/max based on the non-surface data */
-	for (i = 0; i < nr; i++) {
-		struct plot_data *entry = pi->entry+i;
-		int pressure = GET_PRESSURE(entry);
-		int temperature = entry->temperature;
-
-		if (pressure) {
-			if (pressure > pi->maxpressure)
-				pi->maxpressure = pressure;
-			pi->endpressure = pressure;
-		}
-
-		if (temperature) {
-			if (!pi->mintemp || temperature < pi->mintemp)
-				pi->mintemp = temperature;
-			if (temperature > pi->maxtemp)
-				pi->maxtemp = temperature;
-			pi->endtemp = temperature;
-		}
-	}
-
 	/* Smoothing function: 5-point triangular smooth */
 	for (i = 2; i < nr; i++) {
 		struct plot_data *entry = pi->entry+i;
@@ -1693,6 +1672,73 @@ static int count_gas_change_events(struct divecomputer *dc)
 	return count;
 }
 
+static void calculate_max_limits(struct dive *dive, struct graphics_context *gc)
+{
+	struct divecomputer *dc;
+	struct plot_info *pi;
+	int maxdepth = 0;
+	int maxtime = 0;
+	int maxpressure = 0, minpressure = INT_MAX;
+	int mintemp = 0, maxtemp = 0;
+	int cyl;
+
+	/* The plot-info is embedded in the graphics context */
+	pi = &gc->pi;
+	memset(pi, 0, sizeof(*pi));
+
+	/* This should probably have been per-dive-computer */
+	maxdepth = dive->maxdepth.mm;
+	mintemp = maxtemp = dive->watertemp.mkelvin;
+
+	/* Get the per-cylinder maximum pressure if they are manual */
+	for (cyl = 0; cyl < MAX_CYLINDERS; cyl++) {
+		unsigned int mbar = dive->cylinder[cyl].start.mbar;
+		if (mbar > maxpressure)
+			maxpressure = mbar;
+	}
+
+	/* Then do all the samples from all the dive computers */
+	dc = &dive->dc;
+	do {
+		int i = dc->samples;
+		int lastdepth = 0;
+		struct sample *s = dc->sample;
+
+		while (--i >= 0) {
+			int depth = s->depth.mm;
+			int pressure = s->cylinderpressure.mbar;
+			int temperature = s->temperature.mkelvin;
+
+			if (!mintemp && temperature < mintemp)
+				mintemp = temperature;
+			if (temperature > maxtemp)
+				maxtemp = temperature;
+
+			if (pressure && pressure < minpressure)
+				minpressure = pressure;
+			if (pressure > maxpressure)
+				maxpressure = pressure;
+
+			if (depth > maxdepth)
+				maxdepth = s->depth.mm;
+			if ((depth || lastdepth) && s->time.seconds > maxtime)
+				maxtime = s->time.seconds;
+			lastdepth = depth;
+			s++;
+		}
+	} while ((dc = dc->next) != NULL);
+
+	if (minpressure > maxpressure)
+		minpressure = 0;
+
+	pi->maxdepth = maxdepth;
+	pi->maxtime = maxtime;
+	pi->maxpressure = maxpressure;
+	pi->minpressure = minpressure;
+	pi->mintemp = mintemp;
+	pi->maxtemp = maxtemp;
+}
+
 /*
  * Create a plot-info with smoothing and ranged min/max
  *
@@ -1715,7 +1761,6 @@ static struct plot_info *create_plot_info(struct dive *dive, struct divecomputer
 
 	/* The plot-info is embedded in the graphics context */
 	pi = &gc->pi;
-	memset(pi, 0, sizeof(*pi));
 
 	/* we want to potentially add synthetic plot_info elements for the gas changes */
 	nr = dc->samples + 4 + 2 * count_gas_change_events(dc);
@@ -1809,8 +1854,6 @@ static struct plot_info *create_plot_info(struct dive *dive, struct divecomputer
 			lastindex = i + pi_idx;
 
 		lastdepth = depth;
-		if (depth > pi->maxdepth)
-			pi->maxdepth = depth;
 	}
 	entry = pi->entry + i + pi_idx;
 	/* are there still unprocessed gas changes? that would be very strange */
@@ -1916,17 +1959,6 @@ static struct plot_info *create_plot_info(struct dive *dive, struct divecomputer
 	pi->nr = lastindex+1;
 	while (pi->nr <= i+2 && pi->entry[pi->nr-1].depth > 0)
 		pi->nr++;
-	pi->maxtime = pi->entry[lastindex].sec;
-
-	/* Analyze_plot_info() will do the sample max pressures,
-	 * this handles the manual pressures
-	 */
-	pi->maxpressure = 0;
-	for (cyl = 0; cyl < MAX_CYLINDERS; cyl++) {
-		unsigned int mbar = dive->cylinder[cyl].start.mbar;
-		if (mbar > pi->maxpressure)
-			pi->maxpressure = mbar;
-	}
 
 	pi->meandepth = dive->meandepth.mm;
 
@@ -1984,7 +2016,11 @@ void plot(struct graphics_context *gc, struct dive *dive, scale_mode_t scale)
 		dc = &fakedc;
 	}
 
-	pi = create_plot_info(dive, dc, gc);
+	/*
+	 * Set up limits that are independent of
+	 * the dive computer
+	 */
+	calculate_max_limits(dive, gc);
 
 	/* shift the drawing area so we have a nice margin around it */
 	cairo_translate(gc->cr, drawing_area->x, drawing_area->y);
@@ -2002,6 +2038,9 @@ void plot(struct graphics_context *gc, struct dive *dive, scale_mode_t scale)
 	gc->maxx = (drawing_area->width - 2*drawing_area->x);
 	gc->maxy = (drawing_area->height - 2*drawing_area->y);
 
+	/* This is per-dive-computer. Right now we just do the first one */
+	pi = create_plot_info(dive, dc, gc);
+
 	/* Depth profile */
 	plot_depth_profile(gc, pi);
 	plot_events(gc, pi, dc);