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| author |  Linus Torvalds <torvalds@linux-foundation.org> | 2015-10-25 12:02:08 +0900 |
|---|---|---|
| committer |  Dirk Hohndel <dirk@hohndel.org> | 2015-10-25 13:22:59 +0900 |
| commit | 2b1017c986bf10a490592fba7e85b14df86cd58d (patch) | |
| tree | d7130a28fca1fea9c944e21797bb757448e7869e /libdivecomputer.c | |
| parent | cd1884b29cff57b225e1ab58d0b1dcad25669034 (diff) | |
| download | subsurface-2b1017c986bf10a490592fba7e85b14df86cd58d.tar.gz | |
Interpolate depth for samples that have no depth
When downloading from libdivecomputer, we used to initialize the depth
of a sample to the previous depth. However, at least for the Suunto EON
Steel, you can get sample times without any actual depth reading - the
time might be associated with some ranbdom event rather than a new depth
sample.
Rather than initialize these samples to have the same depth as the
previous one (and then perhaps getting a very sudden jump when the
*real* depth event comes in a second later), initialize the depth
samples to -1, and if that sample doesn't get a real depth, we'll create
an interpolated depth.
It is possible that we should just carry the sample around as not
actually having a depth, and instead just interpolate in the plot_info
generation, but at least right now we have a ton of code that "knows"
that every sample has a depth. Not the least of which is our own save
format.
So generating an interpolated depth seems the path of least resistance,
and at least makes the graph look correct - no odd staircase effect from
other events that happen in between depth samples.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Diffstat (limited to 'libdivecomputer.c')
| -rw-r--r-- | libdivecomputer.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/libdivecomputer.c b/libdivecomputer.c index a9d90d837..b5f90cb35 100644 --- a/libdivecomputer.c +++ b/libdivecomputer.c @@ -231,7 +231,6 @@ static void handle_event(struct divecomputer *dc, struct sample *sample, dc_samp void sample_cb(dc_sample_type_t type, dc_sample_value_t value, void *userdata) { - unsigned int mm; static unsigned int nsensor = 0; struct divecomputer *dc = userdata; struct sample *sample; @@ -252,7 +251,10 @@ sample_cb(dc_sample_type_t type, dc_sample_value_t value, void *userdata) switch (type) { case DC_SAMPLE_TIME: nsensor = 0; - mm = 0; + + // The previous sample gets some sticky values + // that may have been around from before, even + // if there was no new data if (sample) { sample->in_deco = in_deco; sample->ndl.seconds = ndl; @@ -260,11 +262,12 @@ sample_cb(dc_sample_type_t type, dc_sample_value_t value, void *userdata) sample->stopdepth.mm = stopdepth; sample->setpoint.mbar = po2; sample->cns = cns; - mm = sample->depth.mm; } + // Create a new sample. + // Mark depth as negative sample = prepare_sample(dc); sample->time.seconds = value.time; - sample->depth.mm = mm; + sample->depth.mm = -1; finish_sample(dc); break; case DC_SAMPLE_DEPTH: |