iOS Maps - Grid Overlay - ios

I'm looking for a way to overlay the iOS maps with a grid. The complete earth needs to be divided into squares. The location of the user doesn't effect the placement of the squares (In other words; the squares are always placed the same. On every iPhone, no matter where the user is).
I Looked into MKOverlay, but I've never used this so it's very new to me. Also, when zooming in/out should effect the overlay. It's very important that the squares are always covering the same area on the map (For example; A square should be 100mx100m in real world, when you zoom out, the square should cover the same 100x100).
Is there anybody that can point me in the right direction?
Is it possible to draw the grid from een .xml? Example given; On .XML is holding all squares with their coordinates on the map. When the user loads the map, the 100 squares around the user are loaded.

Related

Swift SceneKit - I am trying to figure out if a Node object goes off the screen

Using SceneKit
I want to make the gray transparent box to disappear and only show the colored boxes when the user zooms in.
So I want to detect when that box's edges are starting to fall off the screen as I zoom, so I can hide the gray box accordingly.
First thoughts, but there may be better solutions:
You could do an unprojectPoint on the node and check against screen coordinates, do the +/- math on object size and skip Z. I "think" that would work
You can do some physics based collision detection against an invisible box or plane geometries that acts as your screen edges, has some complexity if your view is changing, but testing would be easy - just leave visible until you get what you want, then isVisible=false
isNode(insideFrustomof: ) - returns boolean on whether it "might" be visible. I'm assuming "might" means obscured by other geometry which in your case, shouldn't matter (edit) on second thought, that doesn't solve your problem but I'll leave it in here for reference.

Prevent GMSMarkers from Scaling on iOS?

I am using GMSMarkers on iOS with the Google Maps API. I have a GMSMarker with a PNG image and no matter my zoom level on the map view the GMSMarker keeps its size respective to the screen. If I zoom in it is 30 points across the screen, and if I am zoomed all the way out on the map it is still 30 points. I do NOT want this to happen, I want the GMSMarker to stay small no matter what the zoom level is. It would be preferable that I do not have to loop through all my GMSMarkers every time the camera zoom changes, as I will be eventually having 50-100 of them on the map.
Is there anyway to keep the GMSMarker small no matter the zoom level on the GMSMapView?
I am using Objective-C, but if someone can only give me help in Swift or even Java I can still make do with that.
You could use a GMSGroundOverlay to add an image to the map which scales along with the map. So instead of a fixed size in pixels like a GMSMarker, it stays a fixed size in metres.
Note that another difference is that a ground overlay also stays oriented with the map, ie if the map is rotated/tilted, the top of the image rotates to point north, instead of staying pointing to the top of the screen like a marker.

Drawing World Map - Performance & Interaction - iOS

I’d like to use a Shapefile to generate an interactive world map. I was able to import the data and use CG Paths to draw the map into one large view.
The map needs to support panning, zooming and touch interaction. For that, I've created a UIScrollView and placed the MapView (large view with all of the countries drawn) into it.
I need to improve two aspects of it:
Performance / rendering
I have drawn the map much larger than the screen size, in order to make it look reasonable when I zoom in. There are a few problems with this. First, when I'm zoomed out, I need the border stroke/line to be wider so they are visible. When I zoom in, I'd like the stroke to be a thinner. Also, when I zoom in, I can still see that the map is a blurry. I don't want to increase the view size too much.
How can I make the map look crisp when I'm zoomed in? I attempted to redraw the map on zoom in, but it takes far too long. Can I somehow only re render onscreen stuff?
Touch Interaction
I need to be able to have a touch event for every different country.
Possible approach?
I was thinking of trying to separate every country onto it’s own view. That should make touches easy to handle. Then I’m thinking I can possibly redraw the appropriate views that are on screen/zoomed to.
I've played with an app that does something similar ("World Maps"), and I can see that when you pan or zoom, the map is blurry for a second but then becomes clear. What is going on there?
use mapkit and provide custom tiles. dont reinvent the wheel and try to write yet another map framework
I think that you have to create different scaled area image from the big map image. how to say... imagine the google map, how it works... I think that provide many different zoom factor image for every area of the world... then merged display on the screen while user need show it ...
use code implemented the map effect is impossible on current iPhone device, out of the ability of the iOS device

Can a map overlay be moved?

I'm displaying several user's locations on a map simultaneously as circles of different colors.
I can do this using an annotation and then when the user's location updates use UIView:animateWithDuration: to move to their new location.
However there is a requirement that the size of the circles reflects the accuracy of the location i.e. very accurate equals a circle of size 10 meters, rough accuracy is represented as a circle of size 500 meters etc.
However there are two problems using annotations for this - the first is how to transform meters into a CGRect on the correct size to draw on the map. And the second is the annotations need to be resized if the user zooms the map.
So I was looking at using an overlay instead as that already has a radius and automatic resizing during zooming built in so it handles those two problems.
However it looks like overlays are meant to be static and their coordinate property is read only.
Is there some way I can make the overlays move as the user's location moves? (other than completely remove it and re-add it?)
[THis is for iOS 7 only]

Show popup window for visible spots on globe

I have a globe, similar to http://mrdoob.github.com/three.js/examples/webgl_trackballcamera_earth.html.
My globe has some spots on different locations (f.ex. Paris, Rome or London). Whenever one of these spots come into view, a popup window with additional information to that location should popup appear, and again disappears when that spot rotates out of view, quite similar to http://workshop.chromeexperiments.com/cloudglobe/.
You need 3D coordinates of those points and you need to transform(rotate or whatever) them with globe. Then use this code http://www.opengl.org/wiki/GluProject_and_gluUnProject_code to get screen space coordinates of those points. After that it is simple question of HTML, CSS and some javascript. You know where they are on screen so, for example, you can put some absolute positioned divs with text. But you will need to check on which side of globe those spots are - use rotation phase of the sphere or z-coordinate of the point or simple do color-based picking to see if this spot is visible.

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