I'm trying to make a fairly complex Raphael JS donut graph.
I got several problems, one of them been the 3D effect, which I'm planning to solve by adding 7 drop shadows (glows) or donut duplicates after eachother, to simulate the 7px thickness of the shape.
How could I do this the best way? Thank you in advance...
Seven shadows don't seem like the best way to do it, because it is computationally expensive, because it won't look nice and because one should generally avoid thinking in terms of pixels when working with vector graphics.
If you want to draw a segment of a cylinder -- draw it. Including the sides. Even with solid colour it will create a reasonable illusion of 3d, and you can make it look nicer by using gradients to simulate lighting. You will have to keep track of which faces are actually visible, but that is the case with pretty much any approach to 3D, including the shadow thing.