cairo/canvas.go
func (v *Context) SetTolerance(tolerance float64) {
	C.cairo_set_tolerance(v.native(), C.double(tolerance))
}
func (v *Context) SetTolerance(tolerance float64) {
	C.cairo_set_tolerance(v.native(), C.double(tolerance))
}
// SetTolerance is a wrapper around cairo_set_tolerance().