Mayor Greg Fischer of Louisville calls the city’s annual Ideas Festival a “democratized” version of the TED conference. The festival scene last week was gathered around an interactive model of Louisville — cranked out on the spot by 3D printers, to 1/1000 scale — which attendees shaped and changed as their inner urban planner desired. The event was a kickoff for Fischer’s new planning initiative, Vision Louisville. City officials have expressed their desire to collect the very best ideas for how the city should develop over the next 25 years, “emphasizing growth, authenticity, preservation, sustainability, and quality of place,” according to the initiative’s website. The million-dollar project is intended to be a highly collaborative effort between the Norwegian planning firm Space Group and Louisville residents.