"Cartes Du Ciel" (CdC): Grid Settings

One thing that irks me to no end in CdC from day one is the grid spacing: When you zoom in, the grid lines jump around, as the grid spacing changes. One possibility would be 30°, 15°, 5°, 1°, 0°30' and 0°15'.

But the default grid spacing is 20°, 15°, 10°, 5°, 2° and so on – which is utterly utterly UTTERLY braindead.

But, do not fret! One can change the settings!

But fuck you very much, there are bugs: Because once you start to set the grid spacing to sensible values, the grid lines start to appear horizontally and vertically at different zoom levels. Seriously, WTF?

But that isn't the worst bug, not by far! At certain zoom levels the grid lines disappear completely! Instead, the "compass rose" appears for no apparent reason whatsoever… (at least here on my Macintosh). I think it is a problem when the grid spacing does not change from one so called "field of view number" to the next – but I could not quite nail the problem. Changing the field of view for a "field of view number" moves things around.

Before I started to curse, I initially wanted to simply write down how to set the grid spacing to sensible values – but it didn't seem possible, so I had to vent some air.

But after some fiddeling I managed to cobble together some working settings (the working values might change with different versions, as the code handling the grid spacing seems buggy…).

Setup > Chart, coordinates > Field of vision

Set the following values:

Field Number	"From" value
1	0.75 (was 0.50)
2	1.0
3	2.0 (was 1.5)
4	5.0
5	10.0
6	30.0 (was 20.0)
7	45.0
8	90.0
9	180.0
10	310.0

Setup > Chart, coordinates > Grid spacing

Set the following values:

Field Number	"Declination grid" value
0	+00 05 00
1	+00 15 00
2	+00 30 00
3	+00 30 00
4	+02 30 00
5	+05 00 00
6	+15 00 00
7	+15 00 00
8	+15 00 00
9	+45 00 00
10	+45 00 00

For me, these values result in a halfway useful grid being displayed most of the time. Occasionally the jumps between zoom levels are not smooth, but hey…

[Update] I hate CdC. Now that I have set the grid spacing to sensible values, I can now see the grid moving relative to the stars when I scroll around with the cursor! WTF? This is a cesspool. The code for displaying the grid in CdC seems to be horribly buggy.