pombreda / gmapcatcher

Automatically exported from code.google.com/p/gmapcatcher
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Incorrect scale on 7.6.1 #281

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago
What steps will reproduce the problem?
 1. The distance from St John, NB, Canada Main and Union along Main to Chesley
    turn right onto Chesley and to the start of the bridge over the St John river (reversing falls) is 3.1 km according to Google Map directions.
 2. Using a path measuring tool in GIMP on a zoom level 1 export from GmapCatcher shows this route as 1855px. With a scale of 240m/100px that is 4.5km 
 3. I walked this path and it took much less time than 4.5 km would have. 

What version of the product are you using? On what operating system?
7.6.1 on Ubuntu 10.04

Please provide any additional information below.
Using GIMP I overlayed the Google Map in Firefox and the Gmapcatcher zoom level 
1 map. They have identical sizes but the scales are labeled differently.
Perhaps the scale formula is not taking latitude into account. St John is at 
45deg North where the distortion on a Mercator projection will be noticeable.

Original issue reported on code.google.com by gkni...@gmail.com on 3 Oct 2011 at 5:26

GoogleCodeExporter commented 9 years ago
You are correct the scale formula is not taking latitude into account.

Original comment by heldersepu on 3 Oct 2011 at 11:22

GoogleCodeExporter commented 9 years ago
For the Mercator projection, multiplying by the cosine of the latitude gives 
the correct scale. I verified this for St John and for Anchorage Alaska. Of 
course if gmapcatcher is displaying other map projections other formulae may 
apply. 

Original comment by gkni...@gmail.com on 4 Oct 2011 at 7:08

GoogleCodeExporter commented 9 years ago
Scale is now fixed. Also now the scale respects unit selection.

Original comment by kipenros...@gmail.com on 8 Oct 2012 at 2:42

GoogleCodeExporter commented 9 years ago

Original comment by heldersepu on 8 Oct 2012 at 2:42

GoogleCodeExporter commented 9 years ago
Released in 0.8

Original comment by heldersepu on 16 Oct 2012 at 6:06