In Toon Boom Harmony, you can use the Brush tool to draw with bitmap textured lines.
In the Brush Tool Properties view, you will find a series of default textured brushes but you can also create your own collection by importing either PSD or TGA files in the Pen list.
|•||How to Draw with Texture|
|•||Adjusting the Line Texture Parameters|
|•||Creating Texture Brushes|
|•||Erasing Textured Lines|
|•||Hiding the Line Texture|
|•||Adjusting the Line Texture Opacity|