Really hope someone can help me as I'm a bit stuck :S
I have a custom map of an event using the CATiledLayer so users can zoom in and scroll around the map. What I would like to do now is add the functionality to let the user know where they currently are on the map. I know it can be done as I've seen an app do this before. I'm not sure how to go about doing it though, maybe I need to convert lat/lon into pixels but I'm not sure if thats possible (depending on how big the image is, etc).
On another site it was mentioned to find out the boundaries of the map and then I can add pins to the map, but I'm not sure how to go about doing this? Will I need to find every coordinate (lat/lon) within the boundary so I can add the pin of where the user is currently?
If anyone can give me with any advice or pointers, I'd much appreciate it
You can use the route-me library by adding your own map source class. A good article that explains how to do it is here http://mobilegeo.wordpress.com/2010/07/07/route-me-native-iphone-mapping-framework/
I'm facing a challenge right now in trying to map GPS coords to a map that's an artist's rendition. In particular this is for a ski mountain, so the artist's rendition is a "trail map". The trail map is not accurate in that the whole mountain has been squeezed onto the one view, yet the actual topology of the mountain doesn't conform to the drawing.
I've tried several approaches:
1) Triangulation using known GPS coordinates of the lift stations. This is fairly simple to implement, yet this is not accurate enough and the algorithm fails if the rendition differs enough from the GPS map.
2) Creating a uniform grid for both the GPS map and the Trailmap, then doing a mapping from cells in the GPS map to the Trailmap. The downside to this is it can be a lot of busy work with no easy UI for doing it.
3) Calculating the vectors of each lift (being a straight line), find the closet lift station to a given GPS point, and calculate the estimated Trailmap location using this vector.
I'm considering #2, which is essentially the simplest solution. But if you've found a better way, I'd love to hear it.
Related
I want to instantiate an object in some specific coordinates in ARFundation,
I have tried several ways but none convinces me or gives me the result that I want,
One is with a radius with which if you pass that radius you activate an object that is in your position and it already leaves it fixed but it does not convince me because you have to reach the exact point first to be able to visualize it and you already lose accuracy with the radius unless you put a radius of 2cm.
The other, I got from this blog https://blog.anarks2.com/Geolocated-AR-In-Unity-ARFoundation/ but depending on which cardinal point you are looking at, it is instantiated in one place or another (I think I remember that it says that is unfinished)
Does anyone have a proven way since it works and has enough accuracy?
Apple has released something called ARGeoAnchor.
I think it is not yet supported on Unity though.
If you wish, you can use it, with RealityKit been your engine.
https://developer.apple.com/documentation/arkit/argeoanchor
Also, note it is only supported in distinct locations in the US.
From what I could tell so far, it is very accurate, with the problem only been the altitude you wish to put things on.
I use the Leaflet plug-in "Leaflet.ImageOverlay.Rotated.js" to use its L.imageOverlay.rotated(...) thing in order to overlay certain map pieces in various places on top of the normal map.
It does this by taking an image and having me tell it its top-left, top-right and bottom-left coordinates to figure out how to rotate, tilt and stretch/squeeze it properly.
It took me a very long time to figure these coordinates out by hand. For this reason, I'm looking for some sort of "geopositioning mode", perhaps enabled by this extension, which would simply let me click three times on the map to tell it where these points go. That would be so simple for the developers to do and would help so much. It's such an obvious thing to do that I strongly suspect it's already implemented and ready.
Is there such a "mode"? If not, how am I expected to find the positions without spending so much time and trial-and-error as I did for the first overlay map image?
Added: I should also clarify that the image should be shown in this mode so that you can re-adjust the points and watch in real time as the image bends/warps, to get it just right.
you can develop a modul for this problem.
find minimum 4 point on raster map.
click on tilemap for 4 points
than find different slope and distance same 2 points.
maybe you must rotate and use affine transformation.
http://www.econguru.com/heat-map-of-worldwide-gdp-ppp-per-capita-2008/
This is CIA world Factbook map, each country has different color depth based on their GDP number. High GDP country has deeper color.
Right now, I am considering to develop such effect into my iPhone/iPad map app. I may want to use the apple map (probably not google map since iOS 6 has its own map), but I am not sure how to get such effect based on the country the user visited.
For example, the user visited US the most, then the map shows deeper color in US.
I haven't seen such effect in iPhone app yet. Any suggestion would be appreciated!
This should be doable using MapKit and overlays. You would need to construct an overlay for each area of the heat map and then set the color according to the data. I suspect the hardest part is going to be getting the geographic data you need to construct the paths for each region. AFAICT, there's no -pathForState: or -pathForCountry: type of functions in MapKit, so you're going to need to find another source for that information. But in terms of drawing overlays, it's all there in MapKit. Check out this sample code.
EDIT:
This question has some pointers on where to get that data.
You can get the coordinates ready to go in json format from the D3 project on github:
https://github.com/latentflip/d3/blob/master/data/world-countries.json
You can download this json, use NSJsonSerialization with the file to load the json into a Dictionary or an array, and then build your overlays from there.
One other thing: you aren't technically after a heat map; what you're afer is more of a "thematic" map.
Try the LFHeatMap class. Seems to be what you're looking for.
https://github.com/gpolak/LFHeatMap
How to implement a way to measure distances in real time (video camera?) on the iPhone, like this app that uses a card to compare the size of the card with the actual distance?
Are there any other ways to measure distances? Or how to go about doing this using the card method? What framework should I use?
Well you do have something for reference, hence the use of the card. Saying that after watching the a video for the app I can't seem it seems too user friendly.
So you either need a reference of an object that has some known size, or you need to deduct the size from the image. One idea I just had that might help you do it is what the iPhone's 4 flash (I'm sure it's very complicated by it might just work for some stuff).
Here's what I think.
When the user wants to measure something, he takes a picture of it, but you're actually taking two separate images, one with flash on, one with flash off. Then you can analyze the lighting differences in the image and the flash reflection to determine the scale of the image. This will only work for close and not too shining objects I guess.
But that's about the only other way I thought about deducting scale from an image without any fixed objects.
I like Ron Srebro's idea and have thought about something similar -- please share if you get it to work!
An alternative approach would be to use the auto-focus feature of the camera. Point-and-shoot camera's often have a laser range finder that they use to auto-focus. iPhone doesn't have this and the f-stop is fixed. However, users can change the focus by tapping the camera screen. The phone can also switch between regular and macro focus.
If the API exposes the current focus settings, maybe there's a way to use this to determine range?
Another solution may be to use two laser pointers.
Basically you would shine two laser pointers at, say, a wall in parallel. Then, the further back you go, the beams will look closer and closer together in the video, but they will still remain the same distance apart. Then you can easily come up with some formula to measure the distance based on how far apart the dots are in the photo.
See this thread for more details: Possible to measure distance with an iPhone and laser pointer?.
I am creating an iPhone app for OS4.0, and I am attempting to integrate a custom map with a standard MKMapView. I have been provided a map in .eps format (vector image), and I want to somehow overlay this on an MKMapView in and restrict the scrolling boundaries of the map so users cannot scroll outside the boundaries of the custom map. What's the best way to go about this?
I have read some stuff about hosting map tiles on a server, but this seems overly complex for my application. This would just be a map for an attraction roughly the size of a public zoo, so I would think that it would be conceivable to just convert the .eps to a .png file, and overlay it, but this might not give the best performance.
I understand that I could conceivable use a UIScrollView to do the job, but the problem is that I have dynamically generated MKPinAnnotationViews placed on the map, whose position must be based on latitude and longitude, so I can't think on an elegant or reasonable way to do it with a scrollview. Any ideas?
Thanks!
-Matt
Apple has a great bit of example code that will show you what you need to do. Check out the TileMap sample - it is available as part of the (free) WWDC 2010 samples download.
It shows you how to use the gdal2tiles utility to convert an input map into a tree of overlay tiles.
Another good bit of Apple sample code to check out is HazardMap, which is part of the regular SDK samples.