So as the title says, how can i make arbitrary shadows on vector like this without some colored vector on which that shadow will be put?
Billy Kerr suggested a good idea, I'm going to expand on it.
I created a radial gradient with two colors:
White, Opactiy 0%, Location 0%
Black, Opacity 30%, Location 100%
Adjust the bold value depending on how dark you want the shadow.
Adjust the slider depending on how large you want the shadow.
This allows for the shadow to be drawn on almost any color background.
- Use the Mesh Tool to make a mesh around the areas you want the color get darker
- Use the Lasso Tool to select areas to change the color
- With the Direct Selection Tool move the mesh points
Read more about how to work with a mesh here