Picture handling: change data structure to store offset instead timestamp

It makes no sense to store a 64bit time stamp with every picture. Even the
32bit offset (in seconds) from the dive start is WAY overkill. But
switching to that makes the code much more simple in a number of spots.
And makes what is saved to the XML file easier to read, too.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/dive.c b/dive.c
index a04c92198..c1b5cae87 100644
--- a/dive.c
+++ b/dive.c
@@ -2283,13 +2283,14 @@ static bool new_picture_for_dive(struct dive *d, char *filename)
 
 void dive_create_picture(struct dive *d, char *filename, int shift_time)
 {
+	timestamp_t timestamp;
 	if (!new_picture_for_dive(d, filename))
 		return;
 	struct picture *p = alloc_picture();
 	p->filename = filename;
-	picture_load_exif_data(p);
-	if (p->timestamp)
-		p->timestamp += shift_time;
+	picture_load_exif_data(p, &timestamp);
+	if (timestamp)
+		p->offset = timestamp - d->when + shift_time;
 	dive_add_picture(d, p);
 	dive_set_geodata_from_picture(d, p);
 }
@@ -2298,7 +2299,7 @@ void dive_add_picture(struct dive *d, struct picture *newpic)
 {
 	struct picture **pic_ptr = &d->picture_list;
 	/* let's keep the list sorted by time */
-	while( *pic_ptr && (*pic_ptr)->timestamp < newpic->timestamp )
+	while( *pic_ptr && (*pic_ptr)->offset < newpic->offset )
 		pic_ptr = &(*pic_ptr)->next;
 	newpic->next = *pic_ptr;
 	*pic_ptr = newpic;