ARC/INFO layering scheme When BC Environment translates the MOEP files into ARC/INFO, they are split into 10 layers: tctr: Contours tdem: Elevation points and break lines. All 3D lines are put into this layer, although Z-values on individual line vertices are ignored because ARC/ INFO stores only 2D vertices. tcul: Cultural features. Anthropogenic features such as buildings. tcvr: Land Cover. Lines bounding wooded areas, grassland, etc. tntl: Neatlines. Neatlines around 1:20,000, 1:50,000 mapsheet tiles. tsrf: Surface features. Cliffs, scarps, eskers. ttrn: Transportation. Roads, railway, pipelines, bridges. ttxt: Text annotation. All text annotation. twtr: Water features. Rivers, lakes, canals. tmisc: Other features not in the above, and not useful for BC Environment’s mandate. Photo centres. In Figure 4 the Legend shows first the boundary or neat line of MKRF, then the ten TRIM layers with tdem as X’s. TRIM database uses alphanumeric codes to define map features. Figure 5 shows an example of the codes associated with one feature. The field FCODE or feature code contains the alphanumeric code for the map object. Figure 6 shows part of a file used to translate codes to meaningful descriptions of map objects. In this case, the map object is a river or stream.
Figure 4: TRIM data at Malcolm Knapp Research Forest. 688 Forestry Handbook for British Columbia