1. A computer program product, stored on a machine-readable medium, comprising instructions operable to cause a computer to: display all or a portion of an electronic document and at least one brush tool to a user, the electronic document having paths defined by parametric vector curves, the brush tool being indicated by a cursor and having a region of influence; receive a user input selecting a brush tool and positioning the selected brush tool on the electronic document; and change a stylistic property of paths that pass within the region of influence of the selected brush tool in response to a continuous user-controlled gesture of the brush tool, the stylistic property being a vector-based appearance property that varies along a path.