Realistic Borders.

This technique is based on the use of the magic wand tool and a pix by pix scanning.

 

How to draw really realistic borders
1) Take this rough border and let's try to make it clean

Remember that grid produces a hex grid 2 pixels wide.

This border was drawn using the paint brush tool, with a 2 pix width selection and a red foreground color.

We all agree that this is not a clean result...

 2) Work on the original pre-borders map file

See that the region is made of two lightly forested hexes in an arctic place.

 
3) Zoom in as much as needed

Zoom in as much as you need to be able to correctly see every pix (8 to 12 times seems good to me)

 

 4) Use the paint brush with a 1 pix width

Select the paint brush to 1 pix and pick the foreground color you want to take to make your border (here it's red)

 
5) Paint the external angles

Place a red dot at every angle of the region you want to enclose in your border

 

 6) Select the remaining internal grid

Use the magic wand to select the internal remains of the black grid hexes. Make sure you have the border color as a background color now (you can use the reverse color arrows for this)

 
7) delete the selection to get the background color

Once you have checked that your selection only enclose the hexes you wanted, press delete on the keyboard. the background color shall now replace the previous black color of the hexes.

 

 8) The result is very clean

The border is now very clean and do not spread out on the external hexes.