Convert logical screen coordinates to Lat/Long

Question

2.50/5 (2 votes)

See more:

I need to convert logical screen cordinates to latitude/longitude. I have image, which is return from google static api url. the size of returned image is 512x512 and this image is placed to the WPF Image control of size 300x200. When I move with the cursor through the image, I would like to change the mouse position to the coordinatees. Can you help me how to do it?
thank you

Posted 30-Nov-15 6:02am

Jurdo

Add a Solution

Comments

Richard MacCutchan 30-Nov-15 12:35pm

You need to know the coordinates of the section of map from Google. You also need to know the scale factor of pixels to latitude, and pixels to longitude.

Jurdo 30-Nov-15 12:53pm

i read something about mercator projection. but i dont know how to transform X,Y of image control to coordinates

Richard MacCutchan 30-Nov-15 13:01pm

I just told you how. You need to get the starting co-ordinates and the scale values from the image provider.

Jurdo 30-Nov-15 15:36pm

How can I get starting coordinates? This is my URL: https://maps.googleapis.com/maps/api/staticmap?center=48.9533881,18.1742164&zoom=12&size=512x512 ... And when click on the image on position 423x150, i want get new Lat/Long

Richard MacCutchan 1-Dec-15 2:46am

You need to get that information from the Google maps API, as I keep telling you. There is nothing in an image that provides this information.

[no name] 30-Nov-15 19:04pm

Google will provide you with plenty of leads. eg http://stackoverflow.com/questions/833151/screen-co-ordinates-to-latitude-and-longitude. The rest is what programmers do.

Jurdo 2-Dec-15 7:36am

I used equations for web mercator to transform lat/long to the pixels. but i would like to know, how to convert back to lat/long.

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

magred123 · Answer 1 · 2015-12-18T06:49:00

Solution 1

Perhaps you can take a look at Bing Maps? This provides a real map and works with real coordinates.

Posted 18-Dec-15 6:49am

magred123