external/io_grib_share/gridnav.h

   1 /*****************************************************************************
   2  * Todd Hutchinson
   3  * WSI Corporation
   4  * Billerica, MA
   5  *****************************************************************************/
   6
   7 /* This header contains the public interface to the GridNav API. */
   8
   9 typedef struct {
  10   float central_lat;
  11   float central_lon;
  12   int map_proj;
  13   float truelat1;
  14   float truelat2;
  15 } Projection;
  16
  17 typedef struct {
  18   int num_columns;
  19   int num_rows;
  20   float dx;
  21   float dy;
  22   float lat_origin;
  23   float lon_origin;
  24   float origin_column;
  25   float origin_row;
  26 } GridStruct;
  27
  28 typedef struct {
  29   double parm1;
  30   double parm2;
  31   double parm3;
  32   double parm4;
  33   double parm5;
  34   double parm6;
  35   double parm7;
  36 } ProjTransform;
  37
  38 typedef struct {
  39   Projection proj;
  40   GridStruct grid;
  41   ProjTransform proj_transform;
  42 } GridNav;
  43
  44
  45 /* Public Interface */
  46
  47 int GRID_init(float center_lat, float center_lon, int projection,
  48               float truelat1, float truelat2, int num_columns,
  49               int num_rows, float dx, float dy, float lat_origin,
  50               float lon_origin, float origin_column, float origin_row,
  51               GridNav *gridnav);
  52 int GRID_to_latlon(GridNav *gridnav, float column, float row, float *lat,
  53                    float *lon);
  54 int GRID_from_latlon(GridNav *gridnav, float lat, float lon, float *column,
  55                      float *row);
  56 int GRID_rotate_from_earth_coords(GridNav *gridnav, float lon, float u_earth,
  57                                   float v_earth, float *u_grid, float *v_grid);
  58 int GRID_rotate_to_earth_coords(GridNav *gridnav, float lon, float u_grid,
  59                                 float v_grid, float *u_earth, float *v_earth);
  60
  61 #define GRID_LATLON   0
  62 #define GRID_MERCATOR 1
  63 #define GRID_LAMCON   3
  64 #define GRID_POLSTR   5