ExtractLine

Whether the original image is flat or three-dimensional, the line drawing can be fully recognized.
Slide to adjust the thickness of the line drawing, and the window can preview it in real time.
When adjusting the line drawing, you can compare it with the original image in real time.
You can export it to drawing software such as procreate or ps for the next step of painting;
Use translucent paper to cover the line drawing and copy it, which can effectively practice drawing lines.