/***********************************************************************//**
* @brief Pixel-to-spherical deprojection
*
* @param[in] nx X vector length.
* @param[in] ny Y vector length (0=no replication).
* @param[in] sxy Input vector step.
* @param[in] spt Output vector step.
* @param[in] x Vector of projected x coordinates.
* @param[in] y Vector of projected y coordinates.
* @param[out] phi Longitude of the projected point in native spherical
* coordinates [deg].
* @param[out] theta Latitude of the projected point in native spherical
* coordinates [deg].
* @param[out] stat Status return value for each vector element (always 0)
*
* Deproject pixel (x,y) coordinates in the plane of projection to native
* spherical coordinates (phi,theta).
*
* This method has been adapted from the wcslib function prj.c::tanx2s().
* The interface follows very closely that of wcslib. In contrast to the
* wcslib routine, however, the method assumes that the projection has been
* setup previously (as this will be done by the constructor).
***************************************************************************/
void GWcsTAN::prj_x2s(int nx, int ny, int sxy, int spt,
const double* x, const double* y,
double* phi, double* theta, int* stat) const
{
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mx,my
int mx;
int my;
if (ny > 0) {
mx = nx;
my = ny;
}
else {
mx = 1;
my = 1;
ny = nx;
}
// Do x dependence
const double* xp = x;
int rowoff = 0;
int rowlen = nx * spt;
for (int ix = 0; ix < nx; ++ix, rowoff += spt, xp += sxy) {
double xj = *xp + m_x0;
double* phip = phi + rowoff;
for (int iy = 0; iy < my; ++iy, phip += rowlen) {
*phip = xj;
}
}
// Do y dependence
const double* yp = y;
double* phip = phi;
double* thetap = theta;
int* statp = stat;
for (int iy = 0; iy < ny; ++iy, yp += sxy) {
double yj = *yp + m_y0;
double yj2 = yj*yj;
for (int ix = 0; ix < mx; ++ix, phip += spt, thetap += spt) {
double xj = *phip;
double r = std::sqrt(xj*xj + yj2);
if (r == 0.0) {
*phip = 0.0;
}
else {
*phip = gammalib::atan2d(xj, -yj);
}
*thetap = gammalib::atan2d(m_r0, r);
*(statp++) = 0;
}
}
// Return
return;
}
/***********************************************************************//**
* @brief Generic spherical-to-pixel projection
*
* @param[in] nphi Longitude vector length.
* @param[in] ntheta Latitude vector length (0=no replication).
* @param[in] spt Input vector step.
* @param[in] sxy Output vector step.
* @param[in] phi Longitude vector of the projected point in native spherical
* coordinates [deg].
* @param[in] theta Latitude vector of the projected point in native spherical
* coordinates [deg].
* @param[out] x Vector of projected x coordinates.
* @param[out] y Vector of projected y coordinates.
* @param[out] stat Status return value for each vector element (always 0)
*
* Project native spherical coordinates (phi,theta) to pixel (x,y)
* coordinates in the plane of projection.
*
* This method has been adapted from the wcslib function prj.c::sfls2x().
* The interface follows very closely that of wcslib. In contrast to the
* wcslib routine, however, the method assumes that the projection has been
* setup previously (as this will be done by the constructor).
***************************************************************************/
void GWcsSFL::prj_s2x(int nphi, int ntheta, int spt, int sxy,
const double* phi, const double* theta,
double* x, double* y, int* stat) const
{
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mphi,mtheta
int mphi;
int mtheta;
if (ntheta > 0) {
mphi = nphi;
mtheta = ntheta;
}
else {
mphi = 1;
mtheta = 1;
ntheta = nphi;
}
// Do phi dependence
const double* phip = phi;
int rowoff = 0;
int rowlen = nphi * sxy;
for (int iphi = 0; iphi < nphi; ++iphi, rowoff += sxy, phip += spt) {
double xi = m_w[0] * (*phip);
double* xp = x + rowoff;
for (int itheta = 0; itheta < mtheta; ++itheta, xp += rowlen) {
*xp = xi;
}
}
// Do theta dependence
const double* thetap = theta;
double* xp = x;
double* yp = y;
int* statp = stat;
for (int itheta = 0; itheta < ntheta; ++itheta, thetap += spt) {
double xi = gammalib::cosd(*thetap);
double eta = m_w[0] * (*thetap) - m_y0;
for (int iphi = 0; iphi < mphi; ++iphi, xp += sxy, yp += sxy) {
*xp = xi * (*xp) - m_x0;
*yp = eta;
*(statp++) = 0;
}
}
// Return
return;
}
/***********************************************************************//**
* @brief Pixel-to-spherical deprojection
*
* @param[in] nx X vector length.
* @param[in] ny Y vector length (0=no replication).
* @param[in] sxy Input vector step.
* @param[in] spt Output vector step.
* @param[in] x Vector of projected x coordinates.
* @param[in] y Vector of projected y coordinates.
* @param[out] phi Longitude of the projected point in native spherical
* coordinates [deg].
* @param[out] theta Latitude of the projected point in native spherical
* coordinates [deg].
* @param[out] stat Status return value for each vector element (always 0)
*
* Deproject pixel (x,y) coordinates in the plane of projection to native
* spherical coordinates (phi,theta).
*
* This method has been adapted from the wcslib function prj.c::merx2s().
* The interface follows very closely that of wcslib. In contrast to the
* wcslib routine, however, the method assumes that the projection has been
* setup previously (as this will be done by the constructor).
***************************************************************************/
void GWcsMER::prj_x2s(int nx, int ny, int sxy, int spt,
const double* x, const double* y,
double* phi, double* theta, int* stat) const
{
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mx,my
int mx;
int my;
if (ny > 0) {
mx = nx;
my = ny;
}
else {
mx = 1;
my = 1;
ny = nx;
}
// Do x dependence
const double* xp = x;
int rowoff = 0;
int rowlen = nx * spt;
for (int ix = 0; ix < nx; ++ix, rowoff += spt, xp += sxy) {
double s = m_w[1] * (*xp + m_x0);
double* phip = phi + rowoff;
for (int iy = 0; iy < my; ++iy, phip += rowlen) {
*phip = s;
}
}
// Do y dependence
const double* yp = y;
double* thetap = theta;
int* statp = stat;
for (int iy = 0; iy < ny; ++iy, yp += sxy) {
double t = 2.0 * gammalib::atand(std::exp((*yp + m_y0)/m_r0)) - 90.0;
for (int ix = 0; ix < mx; ++ix, thetap += spt) {
*thetap = t;
*(statp++) = 0;
}
}
// Return
return;
}
/***********************************************************************//**
* @brief Pixel-to-spherical deprojection
*
* @param[in] nx X vector length.
* @param[in] ny Y vector length (0=no replication).
* @param[in] sxy Input vector step.
* @param[in] spt Output vector step.
* @param[in] x Vector of projected x coordinates.
* @param[in] y Vector of projected y coordinates.
* @param[out] phi Longitude of the projected point in native spherical
* coordinates [deg].
* @param[out] theta Latitude of the projected point in native spherical
* coordinates [deg].
* @param[out] stat Status return value for each vector element (always 0)
*
* Deproject pixel (x,y) coordinates in the plane of projection to native
* spherical coordinates (phi,theta).
*
* This method has been adapted from the wcslib function prj.c::sflx2s().
* The interface follows very closely that of wcslib. In contrast to the
* wcslib routine, however, the method assumes that the projection has been
* setup previously (as this will be done by the constructor).
***************************************************************************/
void GWcsSFL::prj_x2s(int nx, int ny, int sxy, int spt,
const double* x, const double* y,
double* phi, double* theta, int* stat) const
{
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mx,my
int mx;
int my;
if (ny > 0) {
mx = nx;
my = ny;
}
else {
mx = 1;
my = 1;
ny = nx;
}
// Initialise status code and statistics
int status = 0;
int n_invalid = 0;
// Do x dependence
const double* xp = x;
int rowoff = 0;
int rowlen = nx * spt;
for (int ix = 0; ix < nx; ++ix, rowoff += spt, xp += sxy) {
double s = m_w[1] * (*xp + m_x0);
double* phip = phi + rowoff;
for (int iy = 0; iy < my; ++iy, phip += rowlen) {
*phip = s;
}
}
// Do y dependence
const double* yp = y;
double* phip = phi;
double* thetap = theta;
int* statp = stat;
for (int iy = 0; iy < ny; ++iy, yp += sxy) {
double yj = *yp + m_y0;
double s = std::cos(yj/m_r0);
// Initialise status
int istat = 0;
// Invert s
if (s == 0.0) {
istat = 1;
status = 3;
n_invalid++;
#if defined(G_DEBUG_PRJ)
std::cout << "prj_x2s(Phi)..:";
std::cout << " nx=" << nx;
std::cout << " ny=" << ny;
std::cout << " ix=" << ix;
std::cout << " iy=" << iy;
std::cout << " yp=" << *yp;
std::cout << " yj=" << yj;
std::cout << " phip=" << *phip;
std::cout << " s=" << s;
std::cout << std::endl;
#endif
}
else {
s = 1.0 / s;
}
// ...
double t = m_w[1] * yj;
// ...
for (int ix = 0; ix < mx; ++ix, phip += spt, thetap += spt) {
*phip *= s;
*thetap = t;
*(statp++) = istat;
}
} // endfor: y dependence
// Handle status code
if (status == 3) {
throw GException::wcs_invalid_x_y(G_PRJ_X2S, n_invalid);
}
// Return
return;
}
/***********************************************************************//**
* @brief Generic spherical-to-pixel projection
*
* @param[in] nphi Longitude vector length.
* @param[in] ntheta Latitude vector length (0=no replication).
* @param[in] spt Input vector step.
* @param[in] sxy Output vector step.
* @param[in] phi Longitude vector of the projected point in native spherical
* coordinates [deg].
* @param[in] theta Latitude vector of the projected point in native spherical
* coordinates [deg].
* @param[out] x Vector of projected x coordinates.
* @param[out] y Vector of projected y coordinates.
* @param[out] stat Status return value for each vector element (always 0)
*
* Project native spherical coordinates (phi,theta) to pixel (x,y)
* coordinates in the plane of projection.
*
* This method has been adapted from the wcslib function prj.c::mers2x().
* The interface follows very closely that of wcslib. In contrast to the
* wcslib routine, however, the method assumes that the projection has been
* setup previously (as this will be done by the constructor).
***************************************************************************/
void GWcsMER::prj_s2x(int nphi, int ntheta, int spt, int sxy,
const double* phi, const double* theta,
double* x, double* y, int* stat) const
{
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mphi,mtheta
int mphi;
int mtheta;
if (ntheta > 0) {
mphi = nphi;
mtheta = ntheta;
}
else {
mphi = 1;
mtheta = 1;
ntheta = nphi;
}
// Initialise status code and statistics
//int status = 0;
int n_invalid = 0;
// Do phi dependence
const double* phip = phi;
int rowoff = 0;
int rowlen = nphi * sxy;
for (int iphi = 0; iphi < nphi; ++iphi, rowoff += sxy, phip += spt) {
double xi = m_w[0] * (*phip) - m_x0;
double* xp = x + rowoff;
for (int itheta = 0; itheta < mtheta; ++itheta, xp += rowlen) {
*xp = xi;
}
}
// Do theta dependence
const double* thetap = theta;
double* yp = y;
int* statp = stat;
for (int itheta = 0; itheta < ntheta; ++itheta, thetap += spt) {
double eta;
int istat = 0;
if (*thetap <= -90.0 || *thetap >= 90.0) {
eta = 0.0;
istat = 1;
n_invalid++;
}
else {
eta = m_r0 * std::log(gammalib::tand((*thetap+90.0)/2.0)) - m_y0;
}
for (int iphi = 0; iphi < mphi; ++iphi, yp += sxy) {
*yp = eta;
*(statp++) = istat;
}
}
// Return
return;
}
/***********************************************************************//**
* @brief Generic spherical-to-Cartesian projection
*
* @param[in] nphi Longitude vector length.
* @param[in] ntheta Latitude vector length (0=no replication).
* @param[in] spt Input vector step.
* @param[in] sxy Output vector step.
* @param[in] phi Longitude vector of the projected point in native spherical
* coordinates [deg].
* @param[in] theta Latitude vector of the projected point in native spherical
* coordinates [deg].
* @param[out] x Vector of projected x coordinates.
* @param[out] y Vector of projected y coordinates.
* @param[out] stat Status return value for each vector element (always 0)
*
* Project native spherical coordinates (phi,theta) to Cartesian (x,y)
* coordinates in the plane of projection.
*
* This method has been adapted from the wcslib function prj.c::cars2x().
* The interface follows very closely that of wcslib. In contrast to the
* wcslib routine, however, the method assumes that the projection has been
* setup previsouly (as this will be done by the constructor).
***************************************************************************/
void GWcsSTG::prj_s2x(int nphi, int ntheta, int spt, int sxy,
const double* phi, const double* theta,
double* x, double* y, int* stat) const
{
// Initialize projection if required
if (!m_prjset)
prj_set();
// Set value replication length mphi,mtheta
int mphi;
int mtheta;
if (ntheta > 0) {
mphi = nphi;
mtheta = ntheta;
}
else {
mphi = 1;
mtheta = 1;
ntheta = nphi;
}
// Initialise status code and statistics
int status = 0;
int n_invalid = 0;
// Do phi dependence
const double* phip = phi;
int rowoff = 0;
int rowlen = nphi * sxy;
for (int iphi = 0; iphi < nphi; ++iphi, rowoff += sxy, phip += spt) {
double sinphi;
double cosphi;
sincosd(*phip, &sinphi, &cosphi);
double* xp = x + rowoff;
double* yp = y + rowoff;
for (int itheta = 0; itheta < mtheta; ++itheta) {
*xp = sinphi;
*yp = cosphi;
xp += rowlen;
yp += rowlen;
}
}
// Do theta dependence
const double* thetap = theta;
double* xp = x;
double* yp = y;
int* statp = stat;
for (int itheta = 0; itheta < ntheta; ++itheta, thetap += spt) {
// Compute sine of Theta
double s = 1.0 + sind(*thetap);
// If 1+sine is zero we cannot proceed. Set all pixels to (0,0) and flag
// them as being bad
if (s == 0.0) {
for (int iphi = 0; iphi < mphi; ++iphi, xp += sxy, yp += sxy) {
*xp = 0.0;
*yp = 0.0;
*(statp++) = 1;
n_invalid++;
}
status = 4;
}
// ... otherwise proceed, but if strict bound checking has been requested
// then flag all pixels as bad that have negative sin(theta)
else {
double r = m_w[0] * cosd(*thetap)/s;
for (int iphi = 0; iphi < mphi; ++iphi, xp += sxy, yp += sxy) {
*xp = r*(*xp) - m_x0;
*yp = -r*(*yp) - m_y0;
*(statp++) = 0;
}
}
}
// Handle status code
if (status == 4)
throw GException::wcs_invalid_phi_theta(G_PRJ_S2X, n_invalid);
// Return
return;
}
/***********************************************************************//**
* @brief Generic spherical-to-pixel projection
*
* @param[in] nphi Longitude vector length.
* @param[in] ntheta Latitude vector length (0=no replication).
* @param[in] spt Input vector step.
* @param[in] sxy Output vector step.
* @param[in] phi Longitude vector of the projected point in native spherical
* coordinates [deg].
* @param[in] theta Latitude vector of the projected point in native spherical
* coordinates [deg].
* @param[out] x Vector of projected x coordinates.
* @param[out] y Vector of projected y coordinates.
* @param[out] stat Status return value for each vector element (always 0)
*
* @exception GException::wcs_invalid_phi_theta
* One or more of the (phi,theta) coordinates were invalid, as
* indicated by the stat vector.
*
* Project native spherical coordinates (phi,theta) to pixel (x,y)
* coordinates in the plane of projection.
*
* This method has been adapted from the wcslib function prj.c::mols2x()
* (version 4.20). The interface follows very closely that of wcslib. In
* contrast to the wcslib routine, however, the method assumes that the
* projection has been setup previously (as this will be done by the
* constructor).
***************************************************************************/
void GWcsMOL::prj_s2x(int nphi, int ntheta, int spt, int sxy,
const double* phi, const double* theta,
double* x, double* y, int* stat) const
{
// Set tolerance
const double tol = 1.0e-13;
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mphi,mtheta
int mphi;
int mtheta;
if (ntheta > 0) {
mphi = nphi;
mtheta = ntheta;
}
else {
mphi = 1;
mtheta = 1;
ntheta = nphi;
}
// Initialise status code and statistics
int status = 0;
int n_invalid = 0;
// Do phi dependence
const double* phip = phi;
int rowoff = 0;
int rowlen = nphi * sxy;
for (int iphi = 0; iphi < nphi; ++iphi, rowoff += sxy, phip += spt) {
double xi = m_w[1] * (*phip);
double* xp = x + rowoff;
for (int itheta = 0; itheta < mtheta; ++itheta) {
*xp = xi;
xp += rowlen;
}
}
// Do theta dependence
const double* thetap = theta;
double* xp = x;
double* yp = y;
int* statp = stat;
for (int itheta = 0; itheta < ntheta; ++itheta, thetap += spt) {
// Compute xi and eta
double xi = 0.0;
double eta = 0.0;
if (std::abs(*thetap) == 90.0) {
xi = 0.0;
eta = copysign(m_w[0], *thetap);
}
else if (*thetap == 0.0) {
xi = 1.0;
eta = 0.0;
}
else {
double u = gammalib::pi * std::sin(*thetap * gammalib::deg2rad);
double v0 = -gammalib::pi;
double v1 = gammalib::pi;
double v = u;
for (int k = 0; k < 100; ++k) {
double resid = (v - u) + std::sin(v);
if (resid < 0.0) {
if (resid > -tol) {
break;
}
v0 = v;
}
else {
if (resid < tol) {
break;
}
v1 = v;
}
v = 0.5 * (v0 + v1);
}
double gamma = 0.5 * v;
xi = std::cos(gamma);
eta = std::sin(gamma) * m_w[0];
}
eta -= m_y0;
// Do ...
for (int iphi = 0; iphi < mphi; ++iphi, xp += sxy, yp += sxy, statp += sxy) {
*xp = xi * (*xp) - m_x0;
*yp = eta;
*statp = 0;
}
} // endfor: theta dependence
// Handle status code
if (status == 4) {
throw GException::wcs_invalid_phi_theta(G_PRJ_S2X, n_invalid);
}
// Return
return;
}
/***********************************************************************//**
* @brief Pixel-to-spherical deprojection
*
* @param[in] nx X vector length.
* @param[in] ny Y vector length (0=no replication).
* @param[in] sxy Input vector step.
* @param[in] spt Output vector step.
* @param[in] x Vector of projected x coordinates.
* @param[in] y Vector of projected y coordinates.
* @param[out] phi Longitude of the projected point in native spherical
* coordinates [deg].
* @param[out] theta Latitude of the projected point in native spherical
* coordinates [deg].
* @param[out] stat Status return value for each vector element
*
* @exception GException::wcs_invalid_x_y
* One or more of the (x,y) coordinates were invalid, as indicated
* by the stat vector.
*
* Deproject pixel (x,y) coordinates in the plane of projection to native
* spherical coordinates (phi,theta).
*
* This method has been adapted from the wcslib function prj.c::molx2s()
* (version 4.20). The interface follows very closely that of wcslib. In
* contrast to the wcslib routine, however, the method assumes that the
* projection has been setup previously (as this will be done by the
* constructor).
***************************************************************************/
void GWcsMOL::prj_x2s(int nx, int ny, int sxy, int spt,
const double* x, const double* y,
double* phi, double* theta, int* stat) const
{
// Set tolerance
const double tol = 1.0e-12;
// Initialize projection if required
if (!m_prjset) {
prj_set();
}
// Set value replication length mx,my
int mx;
int my;
if (ny > 0) {
mx = nx;
my = ny;
}
else {
mx = 1;
my = 1;
ny = nx;
}
// Initialise status code and statistics
int status = 0;
int n_invalid = 0;
// Do x dependence
const double* xp = x;
int rowoff = 0;
int rowlen = nx * spt;
for (int ix = 0; ix < nx; ++ix, rowoff += spt, xp += sxy) {
double xj = *xp + m_x0;
double s = m_w[3] * xj;
double t = std::abs(xj) - tol;
double* phip = phi + rowoff;
double* thetap = theta + rowoff;
for (int iy = 0; iy < my; ++iy, phip += rowlen, thetap += rowlen) {
*phip = s;
*thetap = t;
}
}
// Do y dependence
const double* yp = y;
double* phip = phi;
double* thetap = theta;
int* statp = stat;
for (int iy = 0; iy < ny; ++iy, yp += sxy) {
// Initialise status
int istat = 0;
// Compute some stuff
double yj = *yp + m_y0;
double y0 = yj / m_r0;
double r = 2.0 - y0 * y0;
double s = 0.0;
// Check limits
if (r <= tol) {
if (r < -tol) {
istat = 1;
status = 3;
n_invalid++;
#if defined(G_DEBUG_PRJ)
std::cout << "prj_x2s(Phi)..:";
std::cout << " nx=" << nx;
std::cout << " ny=" << ny;
std::cout << " iy=" << iy;
std::cout << " yp=" << *yp;
std::cout << " yj=" << yj;
std::cout << " y0=" << y0;
std::cout << " phip=" << *phip;
std::cout << " r=" << r;
std::cout << " s=" << s;
std::cout << std::endl;
#endif
}
else {
istat = -1; // OK if fabs(x) < tol whence phi = 0.0
}
r = 0.0;
s = 0.0;
}
else {
r = std::sqrt(r);
s = 1.0 / r;
}
// Compute z and t
double z = yj * m_w[2];
if (std::abs(z) > 1.0) {
if (std::abs(z) > 1.0+tol) {
istat = 1;
status = 3;
n_invalid++;
#if defined(G_DEBUG_PRJ)
std::cout << "prj_x2s(Phi)..:";
std::cout << " nx=" << nx;
std::cout << " ny=" << ny;
std::cout << " iy=" << iy;
std::cout << " yp=" << *yp;
std::cout << " yj=" << yj;
std::cout << " y0=" << y0;
std::cout << " phip=" << *phip;
std::cout << " r=" << r;
std::cout << " s=" << s;
std::cout << " z=" << z;
std::cout << std::endl;
#endif
z = 0.0;
}
else {
z = copysign(1.0, z) + y0 * r / gammalib::pi;
}
}
else {
z = std::asin(z) * m_w[4] + y0 * r / gammalib::pi;
}
if (std::abs(z) > 1.0) {
if (std::abs(z) > 1.0+tol) {
istat = 1;
status = 3;
n_invalid++;
#if defined(G_DEBUG_PRJ)
std::cout << "prj_x2s(Phi)..:";
std::cout << " nx=" << nx;
std::cout << " ny=" << ny;
std::cout << " iy=" << iy;
std::cout << " yp=" << *yp;
std::cout << " yj=" << yj;
std::cout << " y0=" << y0;
std::cout << " phip=" << *phip;
std::cout << " r=" << r;
std::cout << " s=" << s;
std::cout << " z=" << z;
std::cout << std::endl;
#endif
z = 0.0;
}
else {
z = copysign(1.0, z);
}
}
double t = std::asin(z) * gammalib::rad2deg;
// Do ...
for (int ix = 0; ix < mx; ++ix, phip += spt, thetap += spt, statp += spt) {
// Set status flag
if (istat < 0 && *thetap >= 0.0) {
*statp = 1;
status = 3;
n_invalid++;
}
else {
*statp = 0;
}
// Set values
*phip *= s;
*thetap = t;
}
} // endfor: did y dependence
// Handle status code
if (status == 3) {
throw GException::wcs_invalid_x_y(G_PRJ_X2S, n_invalid);
}
// Return
return;
}
