how to draw interchange & color bordes with much more hardiness?

[sayhello]

hello dear experts - good day dear community, 

i have a question;  how to get more hardiness in the colors - especially where two fields meet each other


in other words - see the example: how to get the image and the border of the two different fields 

a. blue 
b. yellow 

in a better shape - with a harder borderline!?

   


i hope that i was able to describe what is needede!?
if i have to explain more - then lemme know.  i love to do that.. - if necessary.


love to hear from you 

[rich2005]

It is anti-aliasing used to smooth lines. Use the pencil tool instead of the paint tool

   

...but... anything other than horizontal or vertical lines will look 'jaggy'

[Ofnuts]

Your blurry frontier spans 8 pixels. As a coincidence this is the size of the JPEG encoding blocks. So whatever sharpness there was in the initiial image has likely been damaged by a JPEG encoding with low quality.