Recalculating route is very slow
Quote from chupa88 on 07.03.2022, 18:07Seems like with the latest version or previous version, the app recalculates the route very slow. This happens when I start navigation on an existing route, or adding via points to an existing route, modifying existing route, as well as importing new route from Google Map links. Sometimes it will take up to 7 or 8 seconds to recalculate a new via or moving a an existing via point when just making minor modifications to an existing route.
Anyone else having this issue? This happens on an iPhone 7 and iPhone 13 Pro.
Seems like with the latest version or previous version, the app recalculates the route very slow. This happens when I start navigation on an existing route, or adding via points to an existing route, modifying existing route, as well as importing new route from Google Map links. Sometimes it will take up to 7 or 8 seconds to recalculate a new via or moving a an existing via point when just making minor modifications to an existing route.
Anyone else having this issue? This happens on an iPhone 7 and iPhone 13 Pro.
Quote from Guido on 07.03.2022, 18:19Your observation is correct. I had to make some changes because the offline routing engine (on the device), in quite some situations, calculated different routes than the online routing engine, and Scenic was using them interchangeably... sometimes using offline (if map data was on the device) and sometimes using online (if some map data was missing). This resulted in routes unexpectedly being different then designed.
Before, if the right map data was on the device (in the form of offline maps or in the temporary map data cache) it would use offline. The map cache changes all the time though, so sometimes it would switch to online if some data was missing, resulting in the routes changing. So now, it will always try online first and only switch to offline calculation if you don't have a connection.
The online routing engine (on the server of the map provider) is a lot better. It has access to a lot more map data details and can therefore calculate a more realistic route. However sending info between device and the server takes time (depending on your connection speed as well) and that's why sometimes the calculations take longer.
Your observation is correct. I had to make some changes because the offline routing engine (on the device), in quite some situations, calculated different routes than the online routing engine, and Scenic was using them interchangeably... sometimes using offline (if map data was on the device) and sometimes using online (if some map data was missing). This resulted in routes unexpectedly being different then designed.
Before, if the right map data was on the device (in the form of offline maps or in the temporary map data cache) it would use offline. The map cache changes all the time though, so sometimes it would switch to online if some data was missing, resulting in the routes changing. So now, it will always try online first and only switch to offline calculation if you don't have a connection.
The online routing engine (on the server of the map provider) is a lot better. It has access to a lot more map data details and can therefore calculate a more realistic route. However sending info between device and the server takes time (depending on your connection speed as well) and that's why sometimes the calculations take longer.
Quote from chupa88 on 08.03.2022, 09:21Thanks for the explanation. Don't know why it's so slow when I'm planning a route at home since the phone is on wifi and I have fiber.
Thanks for the explanation. Don't know why it's so slow when I'm planning a route at home since the phone is on wifi and I have fiber.
Quote from TimeStandStill on 15.03.2022, 21:48Does this change force Scenic to use cellular data, if a connection is available, for every recalculation during a route?
I thought having offline maps downloaded ahead of time would eliminate all mobile data usage by Scenic?
Does this change force Scenic to use cellular data, if a connection is available, for every recalculation during a route?
I thought having offline maps downloaded ahead of time would eliminate all mobile data usage by Scenic?
Quote from rocminc99al on 15.03.2022, 22:26Guido's reply makes me wonder how my old and trusted TomTom 730 circa 2010, that I have used traveling all over the country, didn't have all those issues. Somehow the maps had enough details, and the routing engine was good enough to create very decent routes. This was a device with 1GB of memory and a 2GB memory card. You would think that an average phone has enough memory for a very detail map and enough processing power for a good routing engine.
For navigation, I'm using an old iPhone that doesn't even have a SIM card. If checking the availability of a cellular signal doesn't slow down recalculation, it's probably not a big deal. But if it does, a switch that turns off the use of cellular data won't be such a bad idea.
Guido's reply makes me wonder how my old and trusted TomTom 730 circa 2010, that I have used traveling all over the country, didn't have all those issues. Somehow the maps had enough details, and the routing engine was good enough to create very decent routes. This was a device with 1GB of memory and a 2GB memory card. You would think that an average phone has enough memory for a very detail map and enough processing power for a good routing engine.
For navigation, I'm using an old iPhone that doesn't even have a SIM card. If checking the availability of a cellular signal doesn't slow down recalculation, it's probably not a big deal. But if it does, a switch that turns off the use of cellular data won't be such a bad idea.
Quote from Guido on 15.03.2022, 23:17I also don’t know for sure why the map provider’s offline routing engine is different than the online one in some scenarios.
You are right that the phone’s performance/memory is probably not a limiting factor. I can guess for reasons (offline map packages not having all data that is available online?) but in the end that doesn’t help solve the issue.
The issue being that route calculations should always give the same result…which was not the case.
In the end, I had to make a choice to deal with this situation and make sure route calculations always give the same result.
Option 1) Always default to offline and only go online when not enough map data is on the device. This was what I did in older versions, but got a lot of complaints that routes were changing between and even during design and navigation. Why? Because on first calculation no map data was on the device (if no offline maps for the region), so online was used. During that first calculation, map data is cashed on the device so second calculation (after a detour, or after adding a via) would use offline routing. With sometimes… a different route as a result.
Option 2) Default to online, unless no connection. Then only when no connection is there a chance of a different route.
Option 3) Go for option 1 but make offline map downloads mandatory. (So you are sure offline maps are always on device). I’m quite sure this will upset many people.
I’m open to other ideas
I also don’t know for sure why the map provider’s offline routing engine is different than the online one in some scenarios.
You are right that the phone’s performance/memory is probably not a limiting factor. I can guess for reasons (offline map packages not having all data that is available online?) but in the end that doesn’t help solve the issue.
The issue being that route calculations should always give the same result…which was not the case.
In the end, I had to make a choice to deal with this situation and make sure route calculations always give the same result.
Option 1) Always default to offline and only go online when not enough map data is on the device. This was what I did in older versions, but got a lot of complaints that routes were changing between and even during design and navigation. Why? Because on first calculation no map data was on the device (if no offline maps for the region), so online was used. During that first calculation, map data is cashed on the device so second calculation (after a detour, or after adding a via) would use offline routing. With sometimes… a different route as a result.
Option 2) Default to online, unless no connection. Then only when no connection is there a chance of a different route.
Option 3) Go for option 1 but make offline map downloads mandatory. (So you are sure offline maps are always on device). I’m quite sure this will upset many people.
I’m open to other ideas
Quote from Guido on 15.03.2022, 23:22Quote from rocminc99al on 15.03.2022, 22:26If checking the availability of a cellular signal doesn't slow down recalculation, it's probably not a big deal. But if it does, a switch that turns off the use of cellular data won't be such a bad idea.
If you don’t have a SIM card (and not on WiFi) calculations should be as fast as in older versions. To be sure, You can turn iff cellular data for Scenic through the iOS settings app > Scenic
Quote from rocminc99al on 15.03.2022, 22:26If checking the availability of a cellular signal doesn't slow down recalculation, it's probably not a big deal. But if it does, a switch that turns off the use of cellular data won't be such a bad idea.
If you don’t have a SIM card (and not on WiFi) calculations should be as fast as in older versions. To be sure, You can turn iff cellular data for Scenic through the iOS settings app > Scenic
Quote from rocminc99al on 16.03.2022, 08:00Thanks, Guido. If I understood you correctly, downloading offline maps and turning off cellular data in iOS should result in consistent routing. Hopefully their offline maps are detail enough, and offline routing engine is good enough to create decent routes.
Thanks, Guido. If I understood you correctly, downloading offline maps and turning off cellular data in iOS should result in consistent routing. Hopefully their offline maps are detail enough, and offline routing engine is good enough to create decent routes.
Quote from Guido on 16.03.2022, 08:19Yes. You are correct.
In my experience the offline maps + offline routing engine are good too. Just it makes different choices (different roads) sometimes.
Yes. You are correct.
In my experience the offline maps + offline routing engine are good too. Just it makes different choices (different roads) sometimes.
