On one hand, the landscape reconstruction is created by means of an ecosystem approach. The colormap it's a landscape classification that gives information about different the kinds of soil, and therefore of how should the terrain look according the different land uses. Grass, forest, arable land,... all they look different between them, and at the same time, all the areas classified into an ecosystem look similar. This classification of the vegetation and the creation of the colormap are made for helping the virtual landscape designer to create a realistic environment, because the colormap is obtain from real data. Also easier, because different sets of plants and trees can be dessigned (as many sets as ecosystems), and then apply them to the proper areas. On the other hand, the most of the landscapes editors use the concept of mask for the ecosystem definition. A mask is a binary image, black and white. There should be one mask per ecosystem, because the black areas is where a certain ecosystem exists or not. Visual Nature Studio (VNS) is the only software that allows to use directly colormaps, and automatically assigns every landuse cover to a certain color, and therefore to an area. Therefore, for the rest of the softwares, one of the task that have to be done is the creation of masks from the colormap. This is to issolate the colors, and from each layer to build a new binary image. This task is done easily with the software GIMP, selecting pixels mean color and issolating them, repainting in black, and saving the images as TIFF.
The problem is, when exporting the new images, the georeference information is lost.
One method found for reallocating the images in the proper reference system is using a function in GDAL library. This is an example, where one assigns some parameters to the GDAL_TRANSLATE function, like reference system, or the coordinates of the lower-left corner and the upper-right corner. Here there is a code sample:
gdal_translate -a_srs EPSG:32633 -a_ullr 280018.2306907435995527 4630911.4800800913944840 305544.2781165544292890 4666611.9661431284621358 -of GTiff "C:/Documents and Settings/vhlab/Desktop/Santiago/VIRTUAL_ROME_2.0/GIS-DATASET/colormap/masks/2_Vigneto.TIF" "C:/Documents and Settings/vhlab/Desktop/Santiago/VIRTUAL_ROME_2.0/GIS-DATASET/colormap/masks/2_Vigneto_translate.TIF"
Determination of old land use. Classification:
- Orchard: all soils in the category VU covered by a buffer 50-1500 meters from the villas outside the range of riverine vegetation and out of the buffer zone of villas and monuments (extended 1000) RGB 222,133,187 PINK
- Vineyard: all soils in the category VS and SR covered by a buffer 50-1500 meters from the villas outside the range of riverine vegetation and out of the buffer zone of villas and monuments (extended 2000) 255,0,127 BRIGHT PINK
- Arable land: all soils NOT included in the categories: VU, VS, SR, GG, and covered by a buffer 50-1500 meters from the villas outside the range of riverine vegetation and out of the buffer zone of villas and monuments (extended 3000) RGB 103,218,135 GREEN LIGHT
- Forest: all soils in categories GG and GC out of the range of riverine vegetation and out of the buffer zone of villas and monuments (extended 4000)
- Grass/bush: and all that 'alien to the previous categories and out of the range of riverine vegetation and out of the buffer zone of villas and monuments (val.5000) RGB 88,183,21 GREEN
- Vegetation side streets. everywhere buffer around the roads for 30 meters. (val.6000) RGB 181,66,18 ORANGE
- River vegetation: buffer everywhere around rivers and water courses by distance proportional to the flow rate of rivers (val.1) RGB 15,245,177 CELESTE
- Streets, rivers, buffer. space of all monuments: val. 0 RGB 10,8,179 BLUE