Changeset 9565 in josm for trunk/src/org/openstreetmap/josm/data/projection/proj
 Timestamp:
 20160122T16:50:40+01:00 (5 years ago)
 Location:
 trunk/src/org/openstreetmap/josm/data/projection/proj
 Files:

 1 added
 3 edited
Legend:
 Unmodified
 Added
 Removed

trunk/src/org/openstreetmap/josm/data/projection/proj/AbstractProj.java
r9558 r9565 74 74 */ 75 75 protected double e2; 76 77 /** 78 * is ellipsoid spherical? 79 * @see Ellisoid.spherical 80 */ 81 protected boolean spherical; 76 82 77 83 @Override … … 79 85 e2 = params.ellps.e2; 80 86 e = params.ellps.e; 87 spherical = params.ellps.spherical; 81 88 // Compute constants for the mlfn 82 89 double t; 
trunk/src/org/openstreetmap/josm/data/projection/proj/Mercator.java
r9124 r9565 2 2 package org.openstreetmap.josm.data.projection.proj; 3 3 4 import static java.lang.Math.PI;5 import static java.lang.Math.atan;6 import static java.lang.Math.log;7 import static java.lang.Math.sinh;8 import static java.lang.Math.tan;9 4 import static org.openstreetmap.josm.tools.I18n.tr; 10 5 … … 13 8 14 9 /** 15 * Mercator Projection. 10 * Mercator Cylindrical Projection. The parallels and the meridians are straight lines and 11 * cross at right angles; this projection thus produces rectangular charts. The scale is true 12 * along the equator (by default) or along two parallels equidistant of the equator (if a scale 13 * factor other than 1 is used). This projection is used to represent areas close to the equator. 14 * It is also often used for maritime navigation because all the straight lines on the chart are 15 * <em>loxodrome</em> lines, i.e. a ship following this line would keep a constant azimuth on its 16 * compass. 17 * <p> 18 * This implementation handles both the 1 and 2 stardard parallel cases. 19 * For 1 SP (EPSG code 9804), the line of contact is the equator. 20 * For 2 SP (EPSG code 9805) lines of contact are symmetrical 21 * about the equator. 22 * <p> 23 * This class has been derived from the implementation of the Geotools project; 24 * git 8cbf52d, org.geotools.referencing.operation.projection.CassiniSoldner 25 * at the time of migration. 26 * <p> 27 * <b>References:</b> 28 * <ul> 29 * <li>John P. Snyder (Map Projections  A Working Manual,<br> 30 * U.S. Geological Survey Professional Paper 1395, 1987)</li> 31 * <li>"Coordinate Conversions and Transformations including Formulas",<br> 32 * EPSG Guidence Note Number 7, Version 19.</li> 33 * </ul> 34 * 35 * @see <A HREF="http://mathworld.wolfram.com/MercatorProjection.html">Mercator projection on MathWorld</A> 36 * @see <A HREF="http://www.remotesensing.org/geotiff/proj_list/mercator_1sp.html">"mercator_1sp" on RemoteSensing.org</A> 37 * @see <A HREF="http://www.remotesensing.org/geotiff/proj_list/mercator_2sp.html">"mercator_2sp" on RemoteSensing.org</A> 38 * 39 * @author André Gosselin 40 * @author Martin Desruisseaux (PMO, IRD) 41 * @author Rueben Schulz 42 * @author Simone Giannecchini 16 43 */ 17 public class Mercator implements Proj { 44 public class Mercator extends AbstractProj implements IScaleFactorProvider { 45 /** 46 * Maximum difference allowed when comparing real numbers. 47 */ 48 private static final double EPSILON = 1E6; 49 50 protected double scaleFactor; 18 51 19 52 @Override … … 24 57 @Override 25 58 public String getProj4Id() { 26 return " josm:smerc"; // "merc" is ellipsoidal Mercator projection in PROJ.459 return "merc"; 27 60 } 28 61 29 62 @Override 30 63 public void initialize(ProjParameters params) throws ProjectionConfigurationException { 64 super.initialize(params); 65 scaleFactor = 1; 66 if (params.lat_ts != null) { 67 /* 68 * scaleFactor is not a parameter in the 2 SP case and is computed from 69 * the standard parallel. 70 */ 71 double standardParallel = Math.toRadians(params.lat_ts); 72 if (spherical) { 73 scaleFactor *= Math.cos(standardParallel); 74 } else { 75 scaleFactor *= msfn(Math.sin(standardParallel), Math.cos(standardParallel)); 76 } 77 } 78 /* 79 * A correction that allows us to employs a latitude of origin that is not 80 * correspondent to the equator. See Snyder and al. for reference, page 47. 81 */ 82 if (params.lat0 != null) { 83 final double lat0 = Math.toRadians(params.lat0); 84 final double sinPhi = Math.sin(lat0); 85 scaleFactor *= (Math.cos(lat0) / (Math.sqrt(1  e2 * sinPhi * sinPhi))); 86 } 31 87 } 32 88 33 89 @Override 34 public double[] project(double lat_rad, double lon_rad) { 35 return new double[] {lon_rad, log(tan(PI/4 + lat_rad/2))}; 90 public double[] project(double y, double x) { 91 if (Math.abs(y) > (Math.PI/2  EPSILON)) { 92 return new double[] {0, 0}; // this is an error and should be handled somehow 93 } 94 if (spherical) { 95 y = Math.log(Math.tan(Math.PI/4 + 0.5*y)); 96 } else { 97 y = Math.log(tsfn(y, Math.sin(y))); 98 } 99 return new double[] {x, y}; 36 100 } 37 101 38 102 @Override 39 public double[] invproject(double east, double north) { 40 return new double[] {atan(sinh(north)), east}; 103 public double[] invproject(double x, double y) { 104 if (spherical) { 105 y = Math.PI/2  2.0*Math.atan(Math.exp(y)); 106 } else { 107 y = Math.exp(y); 108 y = cphi2(y); 109 } 110 return new double[] {y, x}; 41 111 } 42 112 … … 45 115 return new Bounds(89, 180, 89, 180, false); 46 116 } 117 118 @Override 119 public double getScaleFactor() { 120 return scaleFactor; 121 } 47 122 } 
trunk/src/org/openstreetmap/josm/data/projection/proj/ProjParameters.java
r9532 r9565 15 15 public Double lat2; 16 16 17 // Polar Stereographic 17 // Polar Stereographic and Mercator 18 18 public Double lat_ts; 19 19
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