Lightning strikes are displayed as uniformly-structured (e.g., gaussian) kernels that decay in size and intensity over time. The lightning strikes may be displayed as they occur, or stored for later display. Overlapping areas of the kernels are displayed in different colors than corresponding non-overlapping...http://www.google.fr/patents/US6560538?utm_source=gb-gplus-shareBrevet US6560538 - Displaying lightning strikes
