IMAGE TEXTURING SYSTEM HAVING THEME CELLS

An image texturing system utilizes theme cells to generate terrain image data area-by-area for a dynamic terrain display. The system is effective in flight simulation apparatus, as for training pilots. A memory stores theme maps representing areas of specific terrains, e.g. terrains lying below a flight path. The theme maps are indexed on a square grid pattern and include a feature identification code (FIC) for each grid point to indicate terrain, e.g. forest, water, etc. A selection device controlled by an image generator selects a current theme map and dissects it cell-by-cell as defined by grid points to provide corner-referenced representations for each theme cell. A terrain storage device stores a library of terrain treatment pattern arrays that are derived, for example, from photo data of forest, ocean, or the like. A terrain treatment pager controlled by the image generator provides representations of select terrain treatments indicated for a current theme cell and selects the terrain treatment required for texturing the current theme cell. A theme element assembler receives the representations for the current theme cell and the select terrain treatments. The cell is specified according to rules for representing one or more terrain treatments. When the range closes to a distance where features would be discernable, representative three-dimensional data for specific objects, e.g. houses, is provided for displays on specific locations. At some point in a flight path, geo-specific data may replace the semi-specific data of simulated terrain.