Index: trunk/src/org/openstreetmap/josm/data/projection/proj/LambertConformalConic.java =================================================================== --- trunk/src/org/openstreetmap/josm/data/projection/proj/LambertConformalConic.java (revision 13638) +++ trunk/src/org/openstreetmap/josm/data/projection/proj/LambertConformalConic.java (revision 13639) @@ -2,5 +2,4 @@ package org.openstreetmap.josm.data.projection.proj; -import static java.lang.Math.PI; import static java.lang.Math.abs; import static java.lang.Math.atan; @@ -11,6 +10,6 @@ import static java.lang.Math.sin; import static java.lang.Math.sqrt; -import static java.lang.Math.tan; import static org.openstreetmap.josm.tools.I18n.tr; +import static org.openstreetmap.josm.tools.Utils.toRadians; import org.openstreetmap.josm.data.Bounds; @@ -18,10 +17,39 @@ import org.openstreetmap.josm.data.projection.Ellipsoid; import org.openstreetmap.josm.data.projection.ProjectionConfigurationException; -import org.openstreetmap.josm.tools.Utils; /** - * Implementation of the Lambert Conformal Conic projection. + * Lambert Conical Conformal Projection. Areas and shapes are deformed as one moves away from standard parallels. + * The angles are true in a limited area. This projection is used for the charts of North America, France and Belgium. + *

+ * This implementation provides transforms for two cases of the lambert conic conformal projection: + *

+ *

+ *

+ * For the 1SP case the latitude of origin is used as the standard parallel (SP). + * To use 1SP with a latitude of origin different from the SP, use the 2SP and set the SP1 to the single SP. + * The {@code "standard_parallel_2"} parameter is optional and will be given the same value + * as {@code "standard_parallel_1"} if not set (creating a 1 standard parallel projection). + *

+ * References: + *

* * @author Pieren + * @author André Gosselin + * @author Martin Desruisseaux (PMO, IRD) + * @author Rueben Schulz + * + * @see Lambert conformal conic projection on MathWorld + * @see lambert_conic_conformal_1sp + * @see lambert_conic_conformal_2sp + * + * @since 13639 (align implementation with proj.4 / GeoTools) + * @since 4285 (reworked from Lambert / LambertCC9Zones) + * @since 2304 (initial implementation by Pieren) */ public class LambertConformalConic extends AbstractProj { @@ -87,11 +115,12 @@ */ protected double n; + /** * projection factor */ protected double f; - /** - * radius of the parallel of latitude of the false origin (2SP) or at - * natural origin (1SP) + + /** + * radius of the parallel of latitude of the false origin (2SP) or at natural origin (1SP) */ protected double r0; @@ -109,7 +138,9 @@ throw new ProjectionConfigurationException(tr("Parameter ''{0}'' required.", Param.lat_0.key)); if (params.lat1 != null && params.lat2 != null) { - initialize2SP(params.lat0, params.lat1, params.lat2); + this.params = new Parameters2SP(params.lat0, params.lat1, params.lat2); + initialize2SP(toRadians(params.lat0), toRadians(params.lat1), toRadians(params.lat2)); } else { - initialize1SP(params.lat0); + this.params = new Parameters1SP(params.lat0); + initialize1SP(toRadians(params.lat0)); } } @@ -118,21 +149,26 @@ * Initialize for LCC with 2 standard parallels. * - * @param lat0 latitude of false origin (in degrees) - * @param lat1 latitude of first standard parallel (in degrees) - * @param lat2 latitude of second standard parallel (in degrees) + * @param lat0 latitude of false origin (in radians) + * @param lat1 latitude of first standard parallel (in radians) + * @param lat2 latitude of second standard parallel (in radians) */ private void initialize2SP(double lat0, double lat1, double lat2) { - this.params = new Parameters2SP(lat0, lat1, lat2); - - final double m1 = m(Utils.toRadians(lat1)); - final double m2 = m(Utils.toRadians(lat2)); - - final double t1 = t(Utils.toRadians(lat1)); - final double t2 = t(Utils.toRadians(lat2)); - final double tf = t(Utils.toRadians(lat0)); - - n = (log(m1) - log(m2)) / (log(t1) - log(t2)); - f = m1 / (n * pow(t1, n)); - r0 = f * pow(tf, n); + + final double cosphi1 = cos(lat1); + final double sinphi1 = sin(lat1); + + final double cosphi2 = cos(lat2); + final double sinphi2 = sin(lat2); + + final double m1 = msfn(sinphi1, cosphi1); + final double m2 = msfn(sinphi2, cosphi2); + + final double t0 = tsfn(lat0, sin(lat0)); + final double t1 = tsfn(lat1, sinphi1); + final double t2 = tsfn(lat2, sinphi2); + + n = log(m1/m2) / log(t1/t2); + f = m1 * pow(t1, -n) / n; + r0 = f * pow(t0, n); } @@ -140,35 +176,13 @@ * Initialize for LCC with 1 standard parallel. * - * @param lat0 latitude of natural origin (in degrees) + * @param lat0 latitude of natural origin (in radians) */ private void initialize1SP(double lat0) { - this.params = new Parameters1SP(lat0); - final double lat0rad = Utils.toRadians(lat0); - - final double m0 = m(lat0rad); - final double t0 = t(lat0rad); - - n = sin(lat0rad); - f = m0 / (n * pow(t0, n)); + final double m0 = msfn(sin(lat0), cos(lat0)); + final double t0 = tsfn(lat0, sin(lat0)); + + n = sin(lat0); + f = m0 * pow(t0, -n) / n; r0 = f * pow(t0, n); - } - - /** - * auxiliary function t - * @param latRad latitude in radians - * @return result - */ - protected double t(double latRad) { - return tan(PI/4 - latRad / 2.0) - / pow((1.0 - e * sin(latRad)) / (1.0 + e * sin(latRad)), e/2); - } - - /** - * auxiliary function m - * @param latRad latitude in radians - * @return result - */ - protected double m(double latRad) { - return cos(latRad) / (sqrt(1 - e * e * pow(sin(latRad), 2))); }