Figures 7-9 show renderings produced for a 2km by 2km region in the Rocky Mountains. This particular region was selected because it includes both rugged and fairly gentle terrain, significant shadowing, a fairly wide range of surface types, and slopes of varying aspect, all within a relatively compact area. The sole source data utilized was standard issue USGS DEM elevation and DOQ image data. A classification map was created as described in Section 2.2. This was used for deshadowing, coloring, and for seeding a plant growth simulation in the manner of Deussen et al. [15], with the individual plants represented using ellipsoids in the spirit of Gardner [7]. For a given time of year, a snow simulation is run and the appropriate parts of the colored orthotexture are replaced with snow color. The texture and plant data was input to a Monte Carlo path tracer [11] with a sky model similar to that used by Yu et al. [23] that appropriately controls illumination based on time/date/place.
Figure 7 shows renderings with and without explicit plant geometry. Figure 8 shows variation of appearance at different times of day. Figure 9 shows variation of appearance at different times of year. Figure 9 shows variations due to seasonal effects.
