The projection type is the equation or equations used by a coordinate system. The following list names the projections MapInfo Pro uses and gives the number used to identify the projection in the MAPINFOW.PRJ file:
| Number | Projection Type |
|---|---|
|
9 |
Albers Equal-Area Conic |
|
28 |
Azimuthal Equidistant (all origin latitudes) |
|
5 |
Azimuthal Equidistant (polar aspect only) |
|
30 |
Cassini-Soldner |
|
2 |
Cylindrical Equal-Area |
|
31 |
Double Stereographic |
|
14 |
Eckert IV |
|
15 |
Eckert VI |
|
6 |
Equidistant Conic, also known as Simple Conic |
|
33 |
Equidistant Cylindrical |
|
34 |
Extended Transverse Mercator |
|
17 |
Gall |
|
7 |
Hotine Oblique Mercator |
|
32 |
Krovak Oblique Conformal Conic (JTSKc) |
|
4 |
Lambert Azimuthal Equal-Area (polar aspect only) |
|
29 |
Lambert Azimuthal Equal-Area |
|
3 |
Lambert Conformal Conic |
|
19 |
Lambert Conformal Conic (modified for Belgium 1972) |
|
1 |
Longitude/Latitude |
|
10 |
Mercator |
|
11 |
Miller Cylindrical |
|
13 |
Mollweide |
|
18 |
New Zealand Map Grid |
|
27 |
Polyconic |
|
26 |
Regional Mercator |
|
12 |
Robinson |
|
16 |
Sinusoidal |
|
20 |
Stereographic |
|
25 |
Swiss Oblique Mercator |
|
8 |
Transverse Mercator, (also known as Gauss-Kruger) |
|
21 |
Transverse Mercator, (modified for Danish System 34 Jylland-Fyn) |
|
22 |
Transverse Mercator, (modified for Danish System 34 Sjaelland) |
|
23 |
Transverse Mercator, (modified for Danish System 34/45 Bornholm) |
|
24 |
Transverse Mercator, (modified for Finnish KKJ) |
Projection numbers in the MAPINFOW.PRJ may be modified by the addition of a constant value to the base number listed in the Projection table, above. Valid values and their meanings are in the next table:
| Constant | Meaning | Parameters |
|---|---|---|
|
1000 |
System has affine transformations |
Affine units specifier and coefficients appear after the regular parameters for the system. |
|
2000 |
System has explicit bounds |
Bounds appear after the regular parameters for the system. |
|
3000 |
System with both affine and bounds |
Affine parameters follow system's parameters; bounds follow affine parameters. |
Example:
Assume you want to work with a simple system based on the Transverse Mercator projection and using the NAD 1983 datum. You might have a line such as the following in your MAPINFOW.PRJ file:
"UTM Zone 1 (NAD 83)", 8, 74, 7, -177, 0, 0.9996, 500000, 0
Now let us say that you want a system based on this, but with an affine transformation specified by the following parameters (see Understanding Affine Transformations): Units=meters; A=0.5; B=-0.866; C=0; D=0.866; E=0.5; and F=0. The required line in the MAPINFOW.PRJ file is:
"UTM Zone 1 (NAD 83) - rotated 60 degrees", 1008, 74, 7, -177, 0, 0.9996, 500000, 0, 7, 0.5, -0.866, 0, 0.866, 0.5, 0
Alternatively, if you want to bound the system to (x1, y1, x2, y2)=(-500000, 0, 500000, 1000000), the required line is:
"UTM Zone 1 (NAD 83) - bounded", 2008, 74, 7, -177, 0, 0.9996, 500000, 0, -500000, 0, 500000, 1000000
To customize the system using both of these modifications, the line is:
"UTM Zone 1 (NAD 83) - rotated and bounded", 3008, 74, 7, -177, 0, 0.9996, 500000, 0, 7, 0.5, -0.866, 0, 0.866, 0.5, 0, -500000, 0, 500000, 1000000