Hi
I would like to ask for some help on drawing lines and measurements onto photographs using OSS tools (on Linux ideally!) I am trying to learn to (hand) draw figure and portrait drawing with correct proportions and perspective. There are a few images that help people understand this in general and I’m studying these, but I’d like to use something like darktable or GIMP to draw rulers and grids over photographs in general. For example I’d like to take photographs and draw guidelines like these:
I’m more than happy to draw the lines manually in e.g. darktable/GIMP, but I’d prefer to have ruler-based measurements e.g. the eyes are 1/2 between top and bottom of the face etc. What tools and workflow can do this easily? What would be the steps to
1 load e.g. JPG/png/webp,
2 draw squares/lines/rectangles/triangles/circles,
3 measure with a ruler,
4 add small text annotations of ruler measurements (one significant fig)
5 save as jpg (ultimately headed for my kindle via a combined pdf using imagemagick!)
(I’m guessing darktable and/or GIMP?)
Thanks!
-Neal