A BGL file is an MS-DOS compatible file that contains scenery information. The structure of a basic BGL file is shown in the following code example.
Header(status information and pointers to data sections)……
Seed Data
Object Data
VOR Data
Facilities Data
Misc. Data
Not all data sections are included in all BGL files. A BGL file can include one or more data sections, and the sections can be in any order. Pointers in the header point to the beginning of each data section, as the following example shows.
;DATABASE HEADER ********************************************************
dw0001;00 world set number (not saved to file list)
dd0004c4eabh;02 N bound 43 degrees meter units
dd000400000h;06 S bound
dd0cf000000h;10 E bound 85 degrees 32-bit pseudo
dd0bf000000h;14 W bound
ddVOR_DATA;18 VOR_DATA
dw50;22 lowest vor freq (channel 0–199)
dw50;24 highest vor freq (108.00–117.95)
ddSYNTH_SEEDS_08;26 seeds level 8
ddSYNTH_SEEDS_09;30 seeds level 9
ddSYNTH_SEEDS_10;34 seeds level 10
ddSYNTH_SEEDS_11;38 seeds level 11
ddSYNTH_SEEDS_12;42 seeds level 12
ddSYNTH_SEEDS_13;46 seeds level 13
ddSYNTH_SEEDS_14;50 seeds level 14
ddSYNTH_SEEDS_15;54 seeds level 15
ddOBJECT_DATA;58 OBJECT_DATA
ddLIBRARY_DATA;62 LIBRARY_DATA
ddFACILITIES_DATA;66 FACILITIES_DATA
ddANCHOR_POINTS;70 ANCHOR POINT DATA
ddCOM_DATA;74 COM RADIO DATA
ddADF_DATA;78 ADF DATA
ddDYN_PATH_DATA;82 DYNAMIC OBJECT PATHS
dw3,3,2,1;86 Library id min
dw5,3,2,1;94 Library id max
ddMISC_DATA;102 MISC_DATA (iom, landme)
ddTITLE_DATA;106 TITLE AND DESCRIPTION DATA
ddMAGDEC_MAP;110 MAGVAR MAP PTR
ddEXCEPTIONS_DATA;114 EXCEPTION LIST PTR
dd0;118 spare 1
dd0;122 (not saved to file list)
dw0;126 (not saved to file list)