3.56 Laggy GPS position (3-4 second delay)
Quote from iafan on 29.03.2024, 16:55Ever since I upgraded to 3.x on my iPhone, the GPS tracking is laggy (I'd say there's a 3-4 seconds delay). For example, I stop by a light to make a turn, and I still see the arrow that depicts the car to be moving towards the intersection. This makes navigation really inconvenient as I have to mentally adjust for the fact that the required turn is much closer than what the map tells me.
Otherwise, the app is snappy, so this is not related to some overall UI lag. There was no issue with the older (2.x) Scenic.
Is this a known issue? I'd be happy to test some beta version and provide some debug logs.
Ever since I upgraded to 3.x on my iPhone, the GPS tracking is laggy (I'd say there's a 3-4 seconds delay). For example, I stop by a light to make a turn, and I still see the arrow that depicts the car to be moving towards the intersection. This makes navigation really inconvenient as I have to mentally adjust for the fact that the required turn is much closer than what the map tells me.
Otherwise, the app is snappy, so this is not related to some overall UI lag. There was no issue with the older (2.x) Scenic.
Is this a known issue? I'd be happy to test some beta version and provide some debug logs.
Quote from Guido on 29.03.2024, 16:57There is a setting in Settings > Finetuning > Extrapolate Position. Let me know if that helps.
There is a setting in Settings > Finetuning > Extrapolate Position. Let me know if that helps.
Quote from iafan on 02.04.2024, 11:04A quick follow-up: turning this feature on fixed the issue for me, so thanks a lot! Maybe makes sense to have it enabled by default for others as well.
A quick follow-up: turning this feature on fixed the issue for me, so thanks a lot! Maybe makes sense to have it enabled by default for others as well.
Quote from WayneAK on 16.10.2024, 19:46Hi, with the new update, where is the setting now? I have trouble following the GPS navigation because it is about 2-3 seconds delay. By the time the arrow is at the intersection for turning, my actual position is about 50 feet away. Therefore I miss all the turns. 🙁
Please help me to fix this!
Hi, with the new update, where is the setting now? I have trouble following the GPS navigation because it is about 2-3 seconds delay. By the time the arrow is at the intersection for turning, my actual position is about 50 feet away. Therefore I miss all the turns. 🙁
Please help me to fix this!
Quote from Guido on 16.10.2024, 20:23Working on it
Working on it
Quote from Guido on 17.10.2024, 11:45I'm hoping to have 4.03 in the App Store in Saturday. The fix will probably not be in that version, but in the one after that.
I'm hoping to have 4.03 in the App Store in Saturday. The fix will probably not be in that version, but in the one after that.
Quote from KM on 22.10.2024, 02:52Has the settings, fine tuning, extrapolate position been removed from Version 4.03?
It did help but on a 170 mile ride yesterday, when Scenic worked well, I was sbout 15 metres ahead of the marker which would have been a problem were it not a familiar route.
Has the settings, fine tuning, extrapolate position been removed from Version 4.03?
It did help but on a 170 mile ride yesterday, when Scenic worked well, I was sbout 15 metres ahead of the marker which would have been a problem were it not a familiar route.
Quote from Guido on 22.10.2024, 08:09I deliberately removed the extrapolate position. I am in the process of extrapolating the poisition in line with the route you are following. The previous "extrapolate" function was only based on position and heading, and caused deviations from the route at corners, with an unnecessary recalculation as a result.Improvement is coming.
Quote from KM on 27.10.2024, 12:36Tried version 4.04 today and it seemed much better unless zoomed right in but that may be wishful thinking !
Kevin
Tried version 4.04 today and it seemed much better unless zoomed right in but that may be wishful thinking !
Kevin
Quote from Guido on 28.10.2024, 09:38It should be better. Not completely addressed but better.
It should be better. Not completely addressed but better.
Quote from KM on 28.10.2024, 09:44I’m glad that there was a difference. It is definitely better but still not quite right yet. The position marker now stays more or less on the roads as well.
Each iteration is definitely changing rapidly for the better which is very positive.
Thanks
Kevin
I’m glad that there was a difference. It is definitely better but still not quite right yet. The position marker now stays more or less on the roads as well.
Each iteration is definitely changing rapidly for the better which is very positive.
Thanks
Kevin
Quote from Guido on 28.10.2024, 09:56Let me give you some background info on this:
So, navigation apps receive the GPS position from iOS. At the moment the GPS position is received, you already passed that position (unless you are not moving obviously). This is just the way it is. So, there is an inherent delay... always.What most navigation apps do to overcome this, is "predict" / "extrapolate" your position. Some do this based on the route you are following and the speed you are traveling. Others do this based on your heading and your speed. In both scenarios they predict where you will be in 1 second from now. Typically, this 1 second is enough, because iOS sends a new GPS position each second (in a navigation scenario).
Scenic v4.04 predicts your location after 1 second, based on heading and speed. Scenic v4.03 did not predict at all. Now... in some situations, additional processing can cause an additional delay in displaying the location update. For example, checking if you are back on the route, generating the next navigation instruction image, or other processing, can cause an additional delay which may cause your location to seem laggy still.
Wether this delay is noticeable can depend on many things. First of all, I need to do some performance improvements to minimize the impact of additional processing on the delay. But also your device performance may affect this. E.g. older device with a slower processor will affect this as well.
All this is to say, I know it's not perfect yet, but it's better than it was. And I'm still working on improving this more.
Let me give you some background info on this:
So, navigation apps receive the GPS position from iOS. At the moment the GPS position is received, you already passed that position (unless you are not moving obviously). This is just the way it is. So, there is an inherent delay... always.
What most navigation apps do to overcome this, is "predict" / "extrapolate" your position. Some do this based on the route you are following and the speed you are traveling. Others do this based on your heading and your speed. In both scenarios they predict where you will be in 1 second from now. Typically, this 1 second is enough, because iOS sends a new GPS position each second (in a navigation scenario).
Scenic v4.04 predicts your location after 1 second, based on heading and speed. Scenic v4.03 did not predict at all. Now... in some situations, additional processing can cause an additional delay in displaying the location update. For example, checking if you are back on the route, generating the next navigation instruction image, or other processing, can cause an additional delay which may cause your location to seem laggy still.
Wether this delay is noticeable can depend on many things. First of all, I need to do some performance improvements to minimize the impact of additional processing on the delay. But also your device performance may affect this. E.g. older device with a slower processor will affect this as well.
All this is to say, I know it's not perfect yet, but it's better than it was. And I'm still working on improving this more.
Quote from KM on 28.10.2024, 11:00Thanks for the explanation. Its only really noticeable when I zoomed in just to see how close it is. It is certainly as good as my BMW / Garmin Nav 6.
It always interesting to see how close the extrapolation gets you when you pop out of European Alpine tunnels.
Scenic is still a cracking App !
Kevin
Thanks for the explanation. Its only really noticeable when I zoomed in just to see how close it is. It is certainly as good as my BMW / Garmin Nav 6.
It always interesting to see how close the extrapolation gets you when you pop out of European Alpine tunnels.
Scenic is still a cracking App !
Kevin
