image/svg+xml
1. Make a shape. If the shape is not a path, convert it to a path withPath>Object to Path. 2. Adding more nodes with Effects>Modify Path>Add nodes may improve the result.
3. Apply the Edge3d effect with your shape selected.
4. The initial results may need fine tuning. Edge3d makes a clipped group containing your shape and another group which includes the highlight / shadows. Sometimes the lighting may be reversed (see the eyes in step 4). When this happens you have to Path>Reverse the parts of the path that are opposite to what you want, before applying the effect. If all the lighting is reversed you can just change the illumination angle.In or outsetting or scaling a duplicate of your shape can generate a set of shadows/highlights you can recombine with your original shape for different effects.If using many blurred paths slows down Inkscape too much, set the blur quality to minimum in Inkscape preferences, use outline mode, or move things to hidden layers.Another similar effect using a different approach (in Ruby) is at:http://www.colivre.coop.br/bin/view/Aurium/Puff 5. Enter the group of highlights / shadows and select all (Ctrl-A). Then you can fine tune the line width and blur. You can also change the colours. Angle is 0-360 clockwise, 0 = up.Shades is 2 or more, 2 is black and white, higher numbers add greys.Use only black and white leaves space for greys (see shades) but doesn't add them - this looks better sometimes. No effect if shades = 2.Stroke width can be set here and fine tuned later.stdDeviation is similiar to the palette blur parameter, and can be fine tuned later.Blur width and height shouldn't need changing.
E.g. shadows / higlights from an inset copy grouped and clipped with origial. Same, with inset copy on top. E.g. shadows / higlights from an outset copy grouped and clipped with origial
0. To install the effect, if it's not included in your distribution, copy the .py file and the .inx file to the extensions directory in the inkscape system directory, or in the inkscape directory in your home directory.