/* Initialize the General Vertical Near-Side Perspective projection
---------------------------------------------------------------*/
long gvnspforint
(
double r, /* (I) Radius of the earth (sphere) */
double h, /* height above sphere */
double center_long, /* (I) Center longitude */
double center_lat, /* (I) Center latitude */
double false_east, /* x offset in meters */
double false_north /* y offset in meters */
)
{
/* Place parameters in static storage for common use
-------------------------------------------------*/
R = r;
p = 1.0 + h / R;
lon_center = center_long;
false_easting = false_east;
false_northing = false_north;
gctp_sincos(center_lat, &sin_p15, &cos_p15);
/* Report parameters to the user
-----------------------------*/
ptitle("GENERAL VERTICAL NEAR-SIDE PERSPECTIVE");
radius(r);
genrpt(h,"Height of Point Above Surface of Sphere: ");
cenlon(center_long);
cenlat(center_lat);
offsetp(false_easting,false_northing);
return(GCTP_OK);
}
/* Initialize the Lambert Azimuthal Equal Area projection
------------------------------------------------------*/
long lamazforint
(
double r, /* (I) Radius of the earth (sphere) */
double center_long, /* (I) Center longitude */
double center_lat, /* (I) Center latitude */
double false_east, /* x offset in meters */
double false_north /* y offset in meters */
)
{
/* Place parameters in static storage for common use
-------------------------------------------------*/
R = r;
lon_center = center_long;
false_easting = false_east;
false_northing = false_north;
gctp_sincos(center_lat, &sin_lat_o, &cos_lat_o);
/* Report parameters to the user
-----------------------------*/
ptitle("LAMBERT AZIMUTHAL EQUAL-AREA");
radius(r);
cenlon(center_long);
cenlat(center_lat);
offsetp(false_easting,false_northing);
return(GCTP_OK);
}
/* Initialize the ALASKA CONFORMAL projection
-----------------------------------------*/
long alconinvint
(
double r_maj, /* Major axis */
double r_min, /* Minor axis */
double false_east, /* x offset in meters */
double false_north /* y offset in meters */
)
{
double es;
double chi;
double esphi;
/* Place parameters in static storage for common use
-------------------------------------------------*/
r_major = r_maj;
r_minor = r_min;
false_easting = false_east;
false_northing = false_north;
lon_center = -152.0 * D2R;
lat_center = 64.0 * D2R;
n = 6;
es = .006768657997291094;
e = sqrt(es);
acoef[1]= 0.9945303;
acoef[2]= 0.0052083;
acoef[3]= 0.0072721;
acoef[4]= -0.0151089;
acoef[5]= 0.0642675;
acoef[6]= 0.3582802;
bcoef[1]= 0.0;
bcoef[2]= -.0027404;
bcoef[3]= 0.0048181;
bcoef[4]= -0.1932526;
bcoef[5]= -0.1381226;
bcoef[6]= -0.2884586;
esphi = e * sin(lat_center);
chi = 2.0 * atan(tan((HALF_PI + lat_center)/2.0) *
pow(((1.0 - esphi)/(1.0 + esphi)),(e/2.0))) - HALF_PI;
gctp_sincos(chi,&sin_p26,&cos_p26);
/* Report parameters to the user
-----------------------------*/
ptitle("ALASKA CONFORMAL");
radius2(r_major,r_minor);
cenlon(lon_center);
cenlat(lat_center);
offsetp(false_easting,false_northing);
return(GCTP_OK);
}
long obleqforint
(
double r,
double center_long,
double center_lat,
double shape_m,
double shape_n,
double angle,
double false_east,
double false_north
)
{
/* Place parameters in static storage for common use
-------------------------------------------------*/
R = r;
lon_center = center_long;
lat_o = center_lat;
m = shape_m;
n = shape_n;
theta = angle;
false_easting = false_east;
false_northing = false_north;
/* Report parameters to the user (to device set up prior to this call)
-------------------------------------------------------------------*/
ptitle("OBLATED EQUAL-AREA");
radius(R);
cenlon(lon_center);
cenlat(lat_o);
genrpt(m,"Parameter m: ");
genrpt(n,"Parameter n: ");
genrpt(theta,"Theta: ");
offsetp(false_easting,false_northing);
/* Calculate the sine and cosine of the latitude of the center of the map
and store in static storage for common use.
-------------------------------------------*/
gctp_sincos(lat_o, &sin_lat_o, &cos_lat_o);
return(GCTP_OK);
}
/* Initialize the General Lambert Azimuthal Equal Area projection
--------------------------------------------------------------*/
int lamazforint(
double r_maj, /* major axis */
double r_min, /* minor axis */
double center_long, /* (I) Center longitude */
double center_lat, /* (I) Center latitude */
double false_east, /* x offset in meters */
double false_north) /* y offset in meters */
{
/* Place parameters in static storage for common use
-------------------------------------------------*/
R = r_maj;
if(fabs(r_min) < EPSLN ) /* sphere */
{
r_major = r_maj;
r_minor = r_maj;
}
else /* sphere or ellipsoide */
{
r_major = r_maj;
r_minor = r_min;
}
lon_center = center_long;
lat_center = center_lat;
false_easting = false_east;
false_northing = false_north;
tsincos(center_lat, &sin_lat_o, &cos_lat_o);
sinphi1 = sin_lat_o;
cosphi1 = cos_lat_o;
es = 1.0 - SQUARE(r_minor / r_major);
e = sqrt(es);
if(es < 0.00001)
{
ind = 1; /* sphere */
qp = 2.0;
q1 = 2.0;
}
else
{
ind = 0; /* ellipsoid */
qp = (1.0 - es)* (((1.0/(1.0 - es))-(1.0/(2.0*e))*log((1.0 - e)/(1.0 + e))));
if((fabs (lat_center - HALF_PI) <= EPSLN ) || (fabs (lat_center + HALF_PI) <= EPSLN ))
{
/* no other constants needed for LA with North and South polar Aspects lat_center = 90 or -90*/
}
else
{
tsincos(lat_center, &sinphi1, &cosphi1);
q1 = (1.0 - es) * ((sinphi1 / (1.0 - es * sinphi1 * sinphi1))
- (1.0 / (2.0 * e)) *
log((1.0 - e * sinphi1)/(1.0 + e * sinphi1)));
Rq = r_major * sqrt(qp/2.0);
if(fabs(q1) >= fabs(qp))
{
beta1 = HALF_PI * (fabs(q1/qp)/(q1/qp));
}
else
{
beta1 = asinz(q1/qp);
}
tsincos(beta1, &sin_beta1, &cos_beta1);
m1 = cosphi1 / sqrt(1.0 - es * sinphi1 * sinphi1);
D = (r_major * m1)/ (Rq * cos_beta1);
}
}
/* Report parameters to the user
-----------------------------*/
ptitle("LAMBERT AZIMUTHAL EQUAL-AREA");
radius2(r_major, r_minor);
cenlon(center_long);
cenlat(center_lat);
offsetp(false_easting,false_northing);
return(OK);
}
