Outline Shading is the drawing style which uses outlines to define objects and shading that use values or patterns to create volume, form, shadows and light. By using outlines and shading together, the artist can create a more three-dimensional or realistic looking drawing or painting.
The outlines used in Outline Shading can be black line, solid color or hatched/cross-hatched lines. To create a realistic looking drawing, the artist can make use of varying thicknesses of outlines and hatching/cross-hatched lines.
In order to shade an area, the artist uses either a solid color, a pattern, or a gradient to create highlights and shadows to give the area a more realistic look. The actual values and colors chosen for shading an area can vary depending upon the type of object, lighting, and mood the artist is conveying.
Outline Shading can be used in a variety of media including, but not limited to, pencil, ink, watercolor and oils.
To get a better idea of Outline Shading and how it works, please check out the following resources:
-Visual Art: https://www.smarthistory.org/outline-shading/
-Tutorials: https://www.youtube.com/watch?v=0WDsPbWtZWI
-Video Tutorials: https://www.youtube.com/watch?v=NhCwjzmJIl8