openware supporting graphics editing

21.7.16: web.adde/graphics/openware supporting graphics editing:

. see what other open source graphics editors are doing 

from these lists:

https://en.wikipedia.org/wiki/Comparison_of_raster_graphics_editors

https://en.wikipedia.org/wiki/Comparison_of_3D_computer_graphics_software

https://en.wikipedia.org/wiki/Comparison_of_vector_graphics_editors

https://en.wikipedia.org/wiki/Comparison_of_3D_computer_graphics_software

(eg, are there free algorithms for simulating

watercolor and oil paints?)