The radius of the circle is not accurate

I’ve set a radius of my geofence to 2500 meters. I have a point that its distance to the center of this geofence is 2332.84 meters. So it should be inside the geofence. Here it is in Bokeh: You can clearly see the point is outside the geofence, however when I verify the distance with Google Maps you can see it’s the same as the one I’ve calculated:

This is the line of the code:

circle = Circle(x="longitude_deg", y="latitude_deg", radius=2500, fill_color="#ffbdaf", fill_alpha=0.4, line_color="#2471A3")

[bryevdv]

@arashgmn Because the amount of space taken up by the bottom axis is not the same as the amount of space taken up by the left axis. Therefore the central area in the plot frame is not square, even though the HTML canvas is. Therefore: the pixel aspect ratio and the data aspect ratio do not match.

To demonstrate this, note that setting a large min_border:

plot = figure(x_range=(-10,10), y_range=(-10,10), min_border=100)

will force the interior plot frame to actually be square, and you will see your observed effect go away.

Edit:

To be clear, this:

should be of concern whenever the range/scale of the axes are different scales/ranges, unlike my example.

is not the underlying concern. There concern is more generally that the pixel aspect ratio of the plot frame, and the aspect ratio of the data ranges do not match, which can happen with any values of the ranges (yes, even when they are set identical). depending on the pixel dimensions of the frame.

[bryevdv]

If I’ve asked for radius 10, it should touch my gridlines.

@birdsarah Only if the aspect ratios line up is this true. In your case you should be setting match_aspect=True to force the ranges to adjust so that the screen aspect and data aspect ratios to match. That is the only way to ensure circles are circles in data space (since canvas will always draw circles in pixel space)

I am still unfortunately not sure what is the issue in the gmap case, or what to do about it.