[ka-Map-users] equidistant projection assumption

Moran Ben-David moran at placebase.com
Tue Jan 31 16:31:40 EST 2006

Hi all,


I have been going through the kaMap code and noticed what I think is an
assumption that the projection of the map that it is using is equidistant.
Am I right?


I am about to write my own version of various functions such as zoomTo
(where I noticed this assumption), however, I just want to make sure I'm not
wrong in this before I proceed.


Here's a code snippet (kaMap.js) in zoomTo()


this.cellSize = newScale/(oMap.resolution * inchesPerUnit[oMap.units]);


var cpX = cgX / this.cellSize;

var cpY = cgY / this.cellSize;


The translation there from geo to pixel space seems to assume that y (pixel)
is proportional to y (geo) linearly. I think. am I off track here entirely?


Thanks in advance,

Moran Ben-David

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