From f12f9ae8c3b3ed8631254c65572eb76462ec0de9 Mon Sep 17 00:00:00 2001 From: Dirk Hohndel Date: Wed, 8 Jan 2014 21:46:27 +0800 Subject: Change fake profile behavior If no average depth is known the current fake profile behavior is rather unintuitive (we make up an average depth). Instead we should assume that this is a PADI style dive log and give the user a "rectangular" profile (actually, it's a trapecoid as we at least try to enforce a sane ascent / descent speed). If the dive is somewhat longer or deeper (10 min / 10 m) we even add a 3m safety stop at 5m. Added a new dives/test0b that tries to capture the typical cases to test this. Fixes #398 Signed-off-by: Dirk Hohndel --- device.c | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) (limited to 'device.c') diff --git a/device.c b/device.c index 4084c4edb..030368c60 100644 --- a/device.c +++ b/device.c @@ -12,10 +12,10 @@ * To do that, we generate a 6-point profile: * * (0, 0) - * (t0, max_d) * (t1, max_d) - * (t2, d) + * (t2, max_d) * (t3, d) + * (t4, d) * (max_t, 0) * * with the same ascent/descent rates between the @@ -80,6 +80,28 @@ static int fill_samples(struct sample *s, int max_d, int avg_d, int max_t, doubl return 1; } +/* we have no average depth; instead of making up a random average depth + * we should assume either a PADI recrangular profile (for short and/or + * shallow dives) or more reasonably a six point profile with a 3 minute + * safety stop at 5m */ +static void fill_samples_no_avg(struct sample *s, int max_d, int max_t, double slope) +{ + // shallow or short dives are just trapecoids based on the given slope + if (max_d < 10000 || max_t < 600) { + s[1].time.seconds = max_d / slope; s[1].depth.mm = max_d; + s[2].time.seconds = max_t - max_d / slope; s[2].depth.mm = max_d; + } else { + s[1].time.seconds = max_d / slope; + s[1].depth.mm = max_d; + s[2].time.seconds = max_t - max_d / slope - 180; + s[2].depth.mm = max_d; + s[3].time.seconds = max_t - 5000 / slope - 180; + s[3].depth.mm = 5000; + s[4].time.seconds = max_t - 5000 / slope; + s[4].depth.mm = 5000; + } +} + struct divecomputer* fake_dc(struct divecomputer* dc) { static struct sample fake[6]; @@ -105,7 +127,17 @@ struct divecomputer* fake_dc(struct divecomputer* dc) * a reasonable average, let's just make something * up. Note that 'avg_d == max_d' is _not_ a reasonable * average. - */ + * We explicitly treat avg_d == 0 differently */ + if (avg_d == 0) { + /* we try for a sane slope, but bow to the insanity of + * the user supplied data */ + fill_samples_no_avg(fake, max_d, max_t, MAX(2.0 * max_d / max_t, 5000.0 / 60)); + if(fake[3].time.seconds == 0) { // just a 4 point profile + fakedc.samples = 4; + fake[3].time.seconds = max_t; + } + return &fakedc; + } if (avg_d < max_d / 10 || avg_d >= max_d) { avg_d = (max_d+10000)/3; if (avg_d > max_d) -- cgit v1.2.3-70-g09d2