PID Technology

The 3D models (PIDs or PlanetaryInteractiveDioramas) of entire cities developed and under development by Ultramundum Foundation deliver extremely large urban areas for free interactive exploration on a standard personal computer, with an extremely high level of realism and realistic personal / veicular traffic.

PIDs are completely open source and their Tabulae (elements at the base of the technology used) will be freely accessible and modifiable by everybody.

Until today, only portions of a city have been modeled with similar tecnologies, because the data load for a model such this, with undhreds of thousands of buildings, has ever been pohibitive. PIDs allows for interactive exploration on a standard personal computer with a modern video card. Out-of-ordinary powerful computers are not necessary.

Thanks to the patented UltraPeg technology and the geographical Automatic Detail geenrators, PIDs offer an interactive flight on all the city with the possibility of descent to the ground level of any single street to walk amont he buildings. Getting altitude the speed increases accordingly to allow for an exploration experience easy and really natural.

To create this kind of products, new software modules and procedures have been developed, beyond the base procedural parametric technology UltraPeg based on Tabulae.

First, UltraPort supports the jerarchical cellular decomposition of the surface of entire planets; this is achived with the PlanetSector system. It is composed by Tabulae that are capable of automatically generate jearchical planetary surfaces, subdiving progressively in subelements of the same type near the user's Avatar and so producing a variable detail rpresentation of the entire celestial body. In this way, near the observer the terrain appears extremely detailed and the resolution lowers toward the horizon, where there are farther portions; the user-perceived resolution appears constant. An entire planet can be explored interactively and appear highly detailed everywhere, even on low power and memory PCs. The jerarchical PlanetSectors structure id dynamic: when the observer moves, the PlanetSectors toward his direction subdivide in others more detailed, while those at the back are substituted by thier lower-resolution ancestors. The resulting structure is highly dynamic and automatically modifies itself when the Avatar moves, producing entire star systems that allow any kind of trips.

A special debug mode can be activated to see the PlanetSector bounding boxes and coordinates. The coordinate of each planet sector is made from 3 numbers: the PlanetSecor level (0 for the entire planet, 1 for the emisphere, ...), the longitude and the latitude in PlanetSectors form Greenwich and the South pole.

A special debug camera can fly independently of the Avatar position, so that views of the PlanetSectors structure can be obtained. Without it, the system would continuously update the scene to show a detailed view everywhere the Avatar moves.

An automatic generation is needed to visualize every building of a city with highly realistic graphical details. Just think about the fact that a city like Turin has more than one hundred thousands buildings and Rome has more that five hundred thousands: it is clear that it is not possible to employ a human modeler, that would need an extremely large number of work hours. The Automatic Buildings Generator is the answer to this problem. It is a set of Tabulae that is capable of producing buildings from cartographic data imported by the open source software UltraTools. Import is all about jerarchical subdivision of the buildings set on the basis of the largest portion of the base on each PlanetSector. Then an analisys module produces the estimated roof structure. All these informations are inserted into a geographical database that is processed by the Automatic Buildings Generator.

Flowerbeds, like other portions of the environment, have details of the grass and not a simple green surface. The open source importer UltraTools subdivides the polygons defining every area (parks, rivers, boardwalks, cultivations) in portions that are PlanetSectors-aligned. Semantic information (normally the type of usage of the ground) are inserted into the resulting database. PlanetSectors generation Tabulae read the database and call other Tabulae (called PlanetSectorProcessors) that generate the resulting visible surface, without any human intervention. For instance, the park generating Tabula 'plant' the grass and represent the ground as dirt with dry leaves to generate a believable meadow.

Other details, such as boardwalks borders, are generated by specific Tabulae called by the PlanetSectorProcessors (for instance the boardwarlks generator). In the PlanetSector system there are vector informations, not raster. This means that, for instance, the boardwalks borders are not defined by pixels of the satellite imagery changing color, inevitably blurred, but by precise lines (vectors) with spatial coordinates and directions. The automatic detail generators can process structural informations, not more or less blurred portions.

A powerful automatic traffic generation system, already available as an academic research, can be inserted into the cellular-subdivided city structure. Veichles and people walk around the streets and boardwalks to bring to life the entire city.

Any Tabula, the data structure at the root of Ultramundum Foundation's UltraPeg technology, can hold multiple data types. For the Turin city model, informations on buildings positions, root maps, olympic areas placements and specific schematics have been imported from Autocad files and other databases.

The Autocad file importer, called UltraTools, allows for fast and almost automatic acquisition of public databases, converted in a very short time to three-dimensional elements. All these data can then be explored in real-time.

The Foundation can arrange interactive demonstrations on request, because this product can not be freely distributed yet.