05-27-2019, 09:56 AM
Gimp is a bitmap editor, so it works with pixels. Diagonal lines will show the painted pixels as pixelated and raggedy.
What tool are you using? The Pencil does not have anti-aliasing so the edges of diagonal lines are very harsh. If you use the Paintbrush with a soft brush the edges are not harsh. It also depends on the size of your image in pixels. On large images the harsh edges are not so visible.
If you already have an image you can use Filters > Blur > Gaussian Blur to soften the edges.
What tool are you using? The Pencil does not have anti-aliasing so the edges of diagonal lines are very harsh. If you use the Paintbrush with a soft brush the edges are not harsh. It also depends on the size of your image in pixels. On large images the harsh edges are not so visible.
If you already have an image you can use Filters > Blur > Gaussian Blur to soften the edges.