How to get tickmarks on only one side of grid line?

Added by Kristof 3 months ago

Dear gurus,

I'm trying to plot tickmarks similar to the ones used on the old Operational Navigation Charts published by the US Defense Mapping Agency.

Every gridline is marked with tickmarks with one arc-minute spacing. So far so good. I'm scratching my head on how to best plot the tickmarks which are only on one side of the grid line facing away from 0° latitude and longitude respectively. See image below

Crop from ONC M-2

After reading the documentation and experimenting a bit the only way I came up with is using a custom symbol. As the -B machinery is very powerful (and at least for me very complex) there might be a better way to do this. The tickmarks sticking out both sides of the gridline are no problem with -B. I'm struggling with the "one-side-only" ones.

Do you have a clever idea on how to achieve this? A nudge in the right direction is greatly appreciated.

onc.jpg - Crop from ONC M-2 (179 KB)


Replies (2)

RE: How to get tickmarks on only one side of grid line? - Added by Paul 3 months ago

Could you set up an appropriate clip path with psclip before plotting regular two-sided ticks and then undo the clip. That should result in one-sided ticks.

RE: How to get tickmarks on only one side of grid line? - Added by Kristof 3 months ago

Thank you Paul for your idea – I'll give it a spin and see what's easier.

(1-2/2)