Plot dive profile slightly more intelligently.

This actually creates a bounding box and some scale markers.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 82 insertions, 15 deletions

diff --git a/profile.c b/profile.c
index cc3f2485a..3649bc131 100644
--- a/profile.c
+++ b/profile.c
@@ -7,29 +7,96 @@
 
 int selected_dive = 0;
 
+#define ROUND_UP(x,y) ((((x)+(y)-1)/(y))*(y))
+#define MAX(x,y) ((x) > (y) ? (x) : (y))
+
+static int round_seconds_up(int seconds)
+{
+	return MAX(30, ROUND_UP(seconds, 60*10));
+}
+
+static int round_feet_up(int feet)
+{
+	return MAX(45, ROUND_UP(feet+5, 15));
+}
+
+/* Scale to 0,0 -> maxx,maxy */
+#define SCALE(x,y) (x)*maxx/scalex+topx,(y)*maxy/scaley+topy
+
+static void plot(cairo_t *cr, int w, int h, struct dive *dive, int samples, struct sample *sample)
+{
+	int i;
+	double topx, topy, maxx, maxy;
+	double scalex, scaley;
+	int maxtime, maxdepth;
+
+	topx = w / 20.0;
+	topy = h / 20.0;
+	maxx = (w - 2*topx);
+	maxy = (h - 2*topy);
+
+	cairo_set_line_width(cr, 2);
+
+	/* Get plot scaling limits */
+	maxtime = round_seconds_up(dive->duration.seconds);
+	maxdepth = round_feet_up(to_feet(dive->maxdepth));
+
+	/* Depth markers: every 15 ft */
+	scalex = 1.0;
+	scaley = maxdepth;
+	cairo_set_source_rgba(cr, 1, 1, 1, 0.5);
+	for (i = 15; i < maxdepth; i += 15) {
+		cairo_move_to(cr, SCALE(0, i));
+		cairo_line_to(cr, SCALE(1, i));
+	}
+
+	/* Time markers: every 5 min */
+	scalex = maxtime;
+	scaley = 1.0;
+	for (i = 5*60; i < maxtime; i += 5*60) {
+		cairo_move_to(cr, SCALE(i, 0));
+		cairo_line_to(cr, SCALE(i, 1));
+	}
+	cairo_stroke(cr);
+
+	scaley = maxdepth;
+
+	/* Depth profile */
+	cairo_set_source_rgba(cr, 1, 0.2, 0.2, 0.80);
+	cairo_move_to(cr, SCALE(sample->time.seconds, to_feet(sample->depth)));
+	for (i = 1; i < dive->samples; i++) {
+		sample++;
+		cairo_line_to(cr, SCALE(sample->time.seconds, to_feet(sample->depth)));
+	}
+	cairo_stroke(cr);
+
+	/* Bounding box last */
+	scalex = scaley = 1.0;
+	cairo_set_source_rgb(cr, 1, 1, 1);
+	cairo_move_to(cr, SCALE(0,0));
+	cairo_line_to(cr, SCALE(0,1));
+	cairo_line_to(cr, SCALE(1,1));
+	cairo_line_to(cr, SCALE(1,0));
+	cairo_close_path(cr);
+	cairo_stroke(cr);
+
+}
+
 static gboolean expose_event(GtkWidget *widget, GdkEventExpose *event, gpointer data)
 {
 	struct dive *dive = dive_table.dives[selected_dive];
 	cairo_t *cr;
-	int i;
+	int w,h;
+
+	w = widget->allocation.width;
+	h = widget->allocation.height;
 
 	cr = gdk_cairo_create(widget->window);
 	cairo_set_source_rgb(cr, 0, 0, 0);
-	gdk_cairo_rectangle(cr, &event->area);
-	cairo_fill(cr);
+	cairo_paint(cr);
 
-	cairo_set_line_width(cr, 3);
-	cairo_set_source_rgb(cr, 1, 1, 1);
-
-	if (dive->samples) {
-		struct sample *sample = dive->sample;
-		cairo_move_to(cr, sample->time.seconds / 5, to_feet(sample->depth) * 3);
-		for (i = 1; i < dive->samples; i++) {
-			sample++;
-			cairo_line_to(cr, sample->time.seconds / 5, to_feet(sample->depth) * 3);
-		}
-		cairo_stroke(cr);
-	}
+	if (dive->samples)
+		plot(cr, w, h, dive, dive->samples, dive->sample);
 
 	cairo_destroy(cr);