This is an automated email from the ASF dual-hosted git repository.
desruisseaux pushed a commit to branch geoapi-4.0
in repository https://gitbox.apache.org/repos/asf/sis.git
commit 33d5d46b7cbcdb392c6a2c140b204f708bbb6389
Author: Martin Desruisseaux <martin.desruisse...@geomatys.com>
AuthorDate: Mon Jan 24 12:06:56 2022 +0100
Add "Rotated Latitude/Longitude" coordinate operation.
---
.../referencing/provider/RotatedNorthPole.java | 150 +++++++++
.../referencing/provider/RotatedSouthPole.java | 154 +++++++++
.../referencing/provider/package-info.java | 2 +-
.../operation/transform/RotatedPole.java | 357 +++++++++++++++++++++
...g.opengis.referencing.operation.OperationMethod | 2 +
.../referencing/provider/ProvidersTest.java | 4 +-
.../operation/transform/RotatedPoleTest.java | 118 +++++++
.../sis/test/suite/ReferencingTestSuite.java | 1 +
8 files changed, 786 insertions(+), 2 deletions(-)
diff --git
a/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/RotatedNorthPole.java
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/RotatedNorthPole.java
new file mode 100644
index 0000000..22b2ae9
--- /dev/null
+++
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/RotatedNorthPole.java
@@ -0,0 +1,150 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.sis.internal.referencing.provider;
+
+import javax.xml.bind.annotation.XmlTransient;
+import org.opengis.util.FactoryException;
+import org.opengis.parameter.ParameterValueGroup;
+import org.opengis.parameter.ParameterDescriptor;
+import org.opengis.parameter.ParameterDescriptorGroup;
+import org.opengis.referencing.operation.MathTransform;
+import org.opengis.referencing.operation.MathTransformFactory;
+import org.apache.sis.referencing.operation.transform.RotatedPole;
+import org.apache.sis.metadata.iso.citation.Citations;
+import org.apache.sis.parameter.ParameterBuilder;
+import org.apache.sis.parameter.Parameters;
+import org.apache.sis.measure.Longitude;
+import org.apache.sis.measure.Latitude;
+import org.apache.sis.measure.Units;
+
+
+/**
+ * The provider for the NetCDF <cite>Rotated Latitude/Longitude</cite>
coordinate operation.
+ * This is similar to the WMO Rotated Latitude/Longitude but rotating north
pole instead of
+ * south pole.
+ *
+ * @author Martin Desruisseaux (Geomatys)
+ * @version 1.2
+ *
+ * @see <a
href="https://cfconventions.org/cf-conventions/cf-conventions.html#_rotated_pole";>Rotated
pole in CF-conversions</a>
+ *
+ * @since 1.2
+ * @module
+ */
+@XmlTransient
+public final class RotatedNorthPole extends AbstractProvider {
+ /**
+ * For cross-version compatibility.
+ */
+ private static final long serialVersionUID = 3485083285768740448L;
+
+ /**
+ * The operation parameter descriptor for the <cite>grid north pole
latitude</cite> parameter value.
+ *
+ * <!-- Generated by ParameterNameTableGenerator -->
+ * <table class="sis">
+ * <caption>Parameter names</caption>
+ * <tr><td> NetCDF: </td><td> grid_north_pole_latitude </td></tr>
+ * </table>
+ * <b>Notes:</b>
+ * <ul>
+ * <li>No default value</li>
+ * </ul>
+ */
+ private static final ParameterDescriptor<Double> GRID_POLE_LATITUDE;
+
+ /**
+ * The operation parameter descriptor for the <cite>grid north pole
longitude</cite> parameter value.
+ *
+ * <!-- Generated by ParameterNameTableGenerator -->
+ * <table class="sis">
+ * <caption>Parameter names</caption>
+ * <tr><td> NetCDF: </td><td> grid_north_pole_longitude </td></tr>
+ * </table>
+ * <b>Notes:</b>
+ * <ul>
+ * <li>No default value</li>
+ * </ul>
+ */
+ private static final ParameterDescriptor<Double> GRID_POLE_LONGITUDE;
+
+ /**
+ * The operation parameter descriptor for the
<cite>north_pole_grid_longitude</cite> parameter value.
+ * This parameter is optional.
+ *
+ * <!-- Generated by ParameterNameTableGenerator -->
+ * <table class="sis">
+ * <caption>Parameter names</caption>
+ * <tr><td> NetCDF: </td><td> north_pole_grid_longitude </td></tr>
+ * </table>
+ * <b>Notes:</b>
+ * <ul>
+ * <li>Value domain: [-180.0 … 180.0]°</li>
+ * <li>Optional</li>
+ * </ul>
+ */
+ private static final ParameterDescriptor<Double> GRID_POLE_ANGLE;
+
+ /**
+ * The group of all parameters expected by this coordinate operation.
+ */
+ public static final ParameterDescriptorGroup PARAMETERS;
+ static {
+ final ParameterBuilder builder = new
ParameterBuilder().setCodeSpace(Citations.NETCDF, "NetCDF").setRequired(true);
+
+ GRID_POLE_LATITUDE = builder.addName("grid_north_pole_latitude")
+ .createBounded(Latitude.MIN_VALUE, Latitude.MAX_VALUE,
Double.NaN, Units.DEGREE);
+
+ GRID_POLE_LONGITUDE = builder.addName("grid_north_pole_longitude")
+ .createBounded(Longitude.MIN_VALUE, Longitude.MAX_VALUE,
Double.NaN, Units.DEGREE);
+
+ GRID_POLE_ANGLE =
builder.setRequired(false).addName("north_pole_grid_longitude")
+ .createBounded(Longitude.MIN_VALUE, Longitude.MAX_VALUE, 0,
Units.DEGREE);
+
+ PARAMETERS = builder.setRequired(true)
+ .addName("rotated_latitude_longitude")
+ .createGroup(GRID_POLE_LATITUDE, // Note: `RotatedPole`
implementation depends on this parameter order.
+ GRID_POLE_LONGITUDE,
+ GRID_POLE_ANGLE);
+ }
+
+ /**
+ * Constructs a new provider.
+ */
+ public RotatedNorthPole() {
+ super(2, 2, PARAMETERS);
+ }
+
+ /**
+ * Creates a coordinate operation from the specified group of parameter
values.
+ *
+ * @param factory the factory to use for creating the transforms.
+ * @param parameters the group of parameter values.
+ * @return the coordinate operation created from the given parameter
values.
+ * @throws FactoryException if the coordinate operation can not be created.
+ */
+ @Override
+ public MathTransform createMathTransform(final MathTransformFactory
factory, final ParameterValueGroup parameters)
+ throws FactoryException
+ {
+ final Parameters p = Parameters.castOrWrap(parameters);
+ return RotatedPole.rotateNorthPole(factory,
+ p.getValue(GRID_POLE_LONGITUDE),
+ p.getValue(GRID_POLE_LATITUDE),
+ p.getValue(GRID_POLE_ANGLE));
+ }
+}
diff --git
a/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/RotatedSouthPole.java
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/RotatedSouthPole.java
new file mode 100644
index 0000000..734e4b2
--- /dev/null
+++
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/RotatedSouthPole.java
@@ -0,0 +1,154 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.sis.internal.referencing.provider;
+
+import javax.xml.bind.annotation.XmlTransient;
+import org.opengis.util.FactoryException;
+import org.opengis.parameter.ParameterValueGroup;
+import org.opengis.parameter.ParameterDescriptor;
+import org.opengis.parameter.ParameterDescriptorGroup;
+import org.opengis.referencing.operation.MathTransform;
+import org.opengis.referencing.operation.MathTransformFactory;
+import org.apache.sis.referencing.operation.transform.RotatedPole;
+import org.apache.sis.metadata.iso.citation.Citations;
+import org.apache.sis.parameter.ParameterBuilder;
+import org.apache.sis.parameter.Parameters;
+import org.apache.sis.measure.Longitude;
+import org.apache.sis.measure.Latitude;
+import org.apache.sis.measure.Units;
+
+
+/**
+ * The provider for the WMO <cite>Rotated Latitude/Longitude</cite> coordinate
operation.
+ * This is defined by the World Meteorological Organization (WMO) in GRIB2
template 3.1.
+ *
+ * @author Martin Desruisseaux (Geomatys)
+ * @version 1.2
+ * @since 1.2
+ * @module
+ */
+@XmlTransient
+public final class RotatedSouthPole extends AbstractProvider {
+ /**
+ * For cross-version compatibility.
+ */
+ private static final long serialVersionUID = -5970630604222205521L;
+
+ /**
+ * The operation parameter descriptor for the <cite>grid south pole
latitude</cite> parameter value.
+ * This is the geographic latitude (usually in degrees) of the southern
pole of the coordinate system.
+ * The symbol used in GRIB2 template 3.1 is θ<sub>p</sub>.
+ *
+ * <!-- Generated by ParameterNameTableGenerator -->
+ * <table class="sis">
+ * <caption>Parameter names</caption>
+ * <tr><td> NetCDF: </td><td> grid_south_pole_latitude </td></tr>
+ * </table>
+ * <b>Notes:</b>
+ * <ul>
+ * <li>No default value</li>
+ * </ul>
+ */
+ private static final ParameterDescriptor<Double> GRID_POLE_LATITUDE;
+
+ /**
+ * The operation parameter descriptor for the <cite>grid south pole
longitude</cite> parameter value.
+ * This is the geographic longitude (usually in degrees) of the southern
pole of the coordinate system.
+ * The symbol used in GRIB2 template 3.1 is λ<sub>p</sub>.
+ *
+ * <!-- Generated by ParameterNameTableGenerator -->
+ * <table class="sis">
+ * <caption>Parameter names</caption>
+ * <tr><td> NetCDF: </td><td> grid_south_pole_longitude </td></tr>
+ * </table>
+ * <b>Notes:</b>
+ * <ul>
+ * <li>No default value</li>
+ * </ul>
+ */
+ private static final ParameterDescriptor<Double> GRID_POLE_LONGITUDE;
+
+ /**
+ * The operation parameter descriptor for the
<cite>grid_south_pole_angle</cite> parameter value (optional).
+ * This is the angle of rotation about the new polar axis (measured
clockwise when looking from the southern
+ * to the northern pole) of the coordinate system, assuming the new axis
to have been obtained by first
+ * rotating the sphere through λ<sub>p</sub> about the geographic polar
axis, and then rotating through
+ * (90° + θ<sub>p</sub>) degrees so that the southern pole moved along the
(previously rotated) Greenwich meridian.
+ *
+ * <!-- Generated by ParameterNameTableGenerator -->
+ * <table class="sis">
+ * <caption>Parameter names</caption>
+ * <tr><td> NetCDF: </td><td> grid_south_pole_angle </td></tr>
+ * </table>
+ * <b>Notes:</b>
+ * <ul>
+ * <li>Value domain: [-180.0 … 180.0]°</li>
+ * <li>Optional</li>
+ * </ul>
+ */
+ private static final ParameterDescriptor<Double> GRID_POLE_ANGLE;
+
+ /**
+ * The group of all parameters expected by this coordinate operation.
+ */
+ public static final ParameterDescriptorGroup PARAMETERS;
+ static {
+ final ParameterBuilder builder = new
ParameterBuilder().setCodeSpace(Citations.NETCDF, "NetCDF").setRequired(true);
+
+ GRID_POLE_LATITUDE = builder.addName("grid_south_pole_latitude")
+ .createBounded(Latitude.MIN_VALUE, Latitude.MAX_VALUE,
Double.NaN, Units.DEGREE);
+
+ GRID_POLE_LONGITUDE = builder.addName("grid_south_pole_longitude")
+ .createBounded(Longitude.MIN_VALUE, Longitude.MAX_VALUE,
Double.NaN, Units.DEGREE);
+
+ GRID_POLE_ANGLE =
builder.setRequired(false).addName("grid_south_pole_angle")
+ .createBounded(Longitude.MIN_VALUE, Longitude.MAX_VALUE, 0,
Units.DEGREE);
+
+ PARAMETERS = builder.setRequired(true)
+ .addName(Citations.WMO, "Rotated Latitude/longitude")
+ .addName("rotated_latlon_grib")
+ .createGroup(GRID_POLE_LATITUDE, // Note: `RotatedPole`
implementation depends on this parameter order.
+ GRID_POLE_LONGITUDE,
+ GRID_POLE_ANGLE);
+ }
+
+ /**
+ * Constructs a new provider.
+ */
+ public RotatedSouthPole() {
+ super(2, 2, PARAMETERS);
+ }
+
+ /**
+ * Creates a coordinate operation from the specified group of parameter
values.
+ *
+ * @param factory the factory to use for creating the transforms.
+ * @param parameters the group of parameter values.
+ * @return the coordinate operation created from the given parameter
values.
+ * @throws FactoryException if the coordinate operation can not be created.
+ */
+ @Override
+ public MathTransform createMathTransform(final MathTransformFactory
factory, final ParameterValueGroup parameters)
+ throws FactoryException
+ {
+ final Parameters p = Parameters.castOrWrap(parameters);
+ return RotatedPole.rotateSouthPole(factory,
+ p.getValue(GRID_POLE_LONGITUDE),
+ p.getValue(GRID_POLE_LATITUDE),
+ p.getValue(GRID_POLE_ANGLE));
+ }
+}
diff --git
a/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/package-info.java
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/package-info.java
index ecc9b95..466e271 100644
---
a/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/package-info.java
+++
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/package-info.java
@@ -22,7 +22,7 @@
*
* @author Martin Desruisseaux (Geomatys)
* @author Matthieu Bastianelli (Geomatys)
- * @version 1.1
+ * @version 1.2
*
* @see org.apache.sis.referencing.operation.transform.MathTransformProvider
*
diff --git
a/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/transform/RotatedPole.java
b/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/transform/RotatedPole.java
new file mode 100644
index 0000000..5b19036
--- /dev/null
+++
b/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/transform/RotatedPole.java
@@ -0,0 +1,357 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.sis.referencing.operation.transform;
+
+import java.util.List;
+import java.util.Collections;
+import java.io.Serializable;
+import org.opengis.util.FactoryException;
+import org.opengis.referencing.operation.Matrix;
+import org.opengis.referencing.operation.MathTransform;
+import org.opengis.referencing.operation.MathTransform2D;
+import org.opengis.referencing.operation.MathTransformFactory;
+import org.opengis.referencing.operation.TransformException;
+import org.opengis.parameter.GeneralParameterValue;
+import org.opengis.parameter.ParameterValue;
+import org.opengis.parameter.ParameterValueGroup;
+import org.opengis.parameter.ParameterDescriptor;
+import org.opengis.parameter.ParameterDescriptorGroup;
+import org.apache.sis.parameter.DefaultParameterDescriptorGroup;
+import org.apache.sis.parameter.Parameters;
+import org.apache.sis.internal.referencing.provider.RotatedNorthPole;
+import org.apache.sis.internal.referencing.provider.RotatedSouthPole;
+import org.apache.sis.internal.referencing.Formulas;
+import org.apache.sis.internal.util.Numerics;
+import org.apache.sis.internal.util.Constants;
+import org.apache.sis.metadata.iso.citation.Citations;
+import org.apache.sis.referencing.ImmutableIdentifier;
+import org.apache.sis.util.ComparisonMode;
+import org.apache.sis.util.Debug;
+
+import static java.lang.Math.*;
+
+
+/**
+ * Computes latitudes and longitudes on a sphere where the south pole has been
moved to given geographic coordinates.
+ * The parameter values of this transform use the conventions defined in
template 3.1 of GRIB2 format published by the
+ * <a href="https://www.wmo.int/";>World Meteorological Organization</a> (WMO):
+ *
+ * <ol>
+ * <li><b>λ<sub>p</sub>:</b> geographic longitude in degrees of the southern
pole of the coordinate system.</li>
+ * <li><b>θ<sub>p</sub>:</b> geographic latitude in degrees of the southern
pole of the coordinate system.</li>
+ * <li>Angle of rotation in degrees about the new polar axis measured
clockwise when looking from the southern
+ * to the northern pole.</li>
+ * </ol>
+ *
+ * The rotations are applied by first rotating the sphere through
λ<sub>p</sub> about the geographic polar axis,
+ * and then rotating through (θ<sub>p</sub> − (−90°)) degrees so that the
southern pole moved along the
+ * (previously rotated) Greenwich meridian.
+ *
+ * <p>Source and target axis order is (<var>longitude</var>,
<var>latitude</var>).
+ * This is the usual axis order used by Apache SIS for <em>internal</em>
calculations.
+ * If a different axis order is desired (for example for showing coordinates
to the user),
+ * an affine transform can be concatenated to this transform.</p>
+ *
+ * @author Martin Desruisseaux (Geomatys)
+ * @version 1.2
+ * @since 1.2
+ * @module
+ */
+public class RotatedPole extends AbstractMathTransform2D implements
Serializable {
+ /**
+ * For cross-version compatibility.
+ */
+ private static final long serialVersionUID = -8355693495724373931L;
+
+ /**
+ * The parameters used for creating this transform.
+ * They are used for formatting <cite>Well Known Text</cite> (WKT).
+ *
+ * @see #getContextualParameters()
+ */
+ private final ContextualParameters context;
+
+ /**
+ * Sine and cosine of the geographic latitude of the southern pole of the
coordinate system.
+ * The rotation angle to apply is (θ<sub>p</sub> − (−90°)) degrees for the
south pole (−90°),
+ * but we use the following trigonometric identities:
+ *
+ * <p>For the south pole:</p>
+ * <ul>
+ * <li>sin(θ + 90°) = cos(θ)</li>
+ * <li>cos(θ + 90°) = −sin(θ)</li>
+ * </ul>
+ *
+ * <p>For the north pole:</p>
+ * <ul>
+ * <li>sin(θ − 90°) = −cos(θ)</li>
+ * <li>cos(θ − 90°) = sin(θ)</li>
+ * </ul>
+ *
+ * By convention those fields contain the sine and cosine for the south
pole case,
+ * and values with opposite sign for the north pole case.
+ */
+ private final double sinθp, cosθp;
+
+ /**
+ * The inverse of this operation, computed when first needed.
+ *
+ * @see #inverse()
+ */
+ private MathTransform2D inverse;
+
+ /**
+ * Creates the inverse of the given forward operation.
+ *
+ * @see #inverse()
+ */
+ private RotatedPole(final RotatedPole forward) {
+ context = forward.context.inverse(forward.context.getDescriptor(),
RotatedPole::inverseParameter);
+ sinθp = forward.sinθp;
+ cosθp = -forward.cosθp;
+ inverse = forward;
+ }
+
+ /**
+ * Computes the value of the given parameter for the inverse operation.
+ * This method is invoked for each parameter.
+ *
+ * @param forward the forward operation.
+ * @param target parameter to initialize.
+ * @return whether to accept the parameter (always {@code true}).
+ */
+ private static boolean inverseParameter(final Parameters forward, final
ParameterValue<?> target) {
+ final ParameterDescriptor<?> descriptor = target.getDescriptor();
+ final List<GeneralParameterValue> values = forward.values();
+ for (int i = values.size(); --i >= 0;) {
+ if (descriptor.equals(values.get(i).getDescriptor())) {
+ if (i != 0) {
+ /*
+ * For assigning a value to the
"grid_south_pole_longitude" parameter at index 1,
+ * we derive the value from the "grid_south_pole_angle"
parameter at index 2.
+ * And conversely.
+ */
+ i = 3 - i;
+ }
+ double value = -((Number) ((ParameterValue<?>)
values.get(i)).getValue()).doubleValue();
+ if (i == 0) value = Math.IEEEremainder(value + 180, 360);
+ target.setValue(value);
+ return true;
+ }
+ }
+ return false; // Should never happen.
+ }
+
+ /**
+ * Creates the non-linear part of a rotated pole operation.
+ * This transform does not include the conversion between degrees and
radians and the longitude rotations.
+ * For a complete transform, use one of the static factory methods.
+ *
+ * @param south {@code true} for a south pole rotation, or {@code false}
for a north pole rotation.
+ * @param λp geographic longitude in degrees of the southern pole of
the coordinate system.
+ * @param θp geographic latitude in degrees of the southern pole of
the coordinate system.
+ * @param pa angle of rotation in degrees about the new polar axis
measured clockwise when
+ * looking from the southern to the northern pole.
+ */
+ protected RotatedPole(final boolean south, double λp, double θp, double
pa) {
+ context = new ContextualParameters(
+ south ? RotatedSouthPole.PARAMETERS
+ : RotatedNorthPole.PARAMETERS, 2, 2);
+ setValue(0, θp); // grid_south_pole_latitude or
grid_north_pole_latitude
+ setValue(1, λp); // grid_south_pole_longitude or
grid_north_pole_longitude
+ setValue(2, pa); // grid_south_pole_angle or
north_pole_grid_longitude
+ final double θ = toRadians(θp);
+ final double sign = south ? 1 : -1;
+ sinθp = sin(θ) * sign;
+ cosθp = cos(θ) * sign;
+ context.normalizeGeographicInputs(λp);
+ context.denormalizeGeographicOutputs(-pa);
+ }
+
+ /**
+ * Sets the value of the parameter at the given index.
+ * In the rotated south pole case, parameter 0 to 2 (inclusive) are:
+ * {@code "grid_south_pole_latitude"},
+ * {@code "grid_south_pole_longitude"} and
+ * {@code "grid_south_pole_angle"} in that order.
+ */
+ private void setValue(final int index, final double value) {
+ final ParameterDescriptor<?> p = (ParameterDescriptor<?>)
context.getDescriptor().descriptors().get(index);
+ context.parameter(p.getName().getCode()).setValue(value);
+ }
+
+ /**
+ * Creates a new rotated south pole operation.
+ *
+ * @param factory the factory to use for creating the transform.
+ * @param λp geographic longitude in degrees of the southern pole
of the coordinate system.
+ * @param θp geographic latitude in degrees of the southern pole of
the coordinate system.
+ * @param pa angle of rotation in degrees about the new polar axis
measured clockwise when
+ * looking from the southern to the northern pole.
+ * @return the conversion doing a south pole rotation.
+ * @throws FactoryException if an error occurred while creating a
transform.
+ */
+ public static MathTransform rotateSouthPole(final MathTransformFactory
factory,
+ final double λp, final double θp, final double pa) throws
FactoryException
+ {
+ final RotatedPole kernel = new RotatedPole(true, λp, θp, pa);
+ return kernel.context.completeTransform(factory, kernel);
+ }
+
+ /**
+ * Creates a new rotated north pole operation.
+ *
+ * @param factory the factory to use for creating the transform.
+ * @param λp geographic longitude in degrees of the northern pole
of the coordinate system.
+ * @param θp geographic latitude in degrees of the northern pole of
the coordinate system.
+ * @param pa angle of rotation in degrees about the new polar axis
measured clockwise when
+ * looking from the northern to the southern pole.
+ * @return the conversion doing a north pole rotation.
+ * @throws FactoryException if an error occurred while creating a
transform.
+ */
+ public static MathTransform rotateNorthPole(final MathTransformFactory
factory,
+ final double λp, final double θp, final double pa) throws
FactoryException
+ {
+ final RotatedPole kernel = new RotatedPole(false, λp, θp, pa);
+ return kernel.context.completeTransform(factory, kernel);
+ }
+
+ /**
+ * Returns a description of the parameters of this transform. The group of
parameters contains only the grid
+ * (north or south) pole latitude. It does not contain the grid pole
longitude or the grid angle of rotation
+ * because those parameters are handled by affine transforms pre- or
post-concatenated to this transform.
+ *
+ * @return the parameter descriptors for this math transform.
+ */
+ @Debug
+ @Override
+ public ParameterDescriptorGroup getParameterDescriptors() {
+ // We assume that it is not worth to cache this descriptor.
+ ImmutableIdentifier name = new ImmutableIdentifier(Citations.SIS,
Constants.SIS, "Rotated Latitude/longitude (radians domain)");
+ return new
DefaultParameterDescriptorGroup(Collections.singletonMap(ParameterDescriptorGroup.NAME_KEY,
name),
+ 1, 1, (ParameterDescriptor<?>)
context.getDescriptor().descriptors().get(0));
+ }
+
+ /**
+ * Returns a copy of the parameter values of this transform.
+ * The group contains the values of the parameters described by {@link
#getParameterDescriptors()}.
+ * This method is mostly for {@linkplain
org.apache.sis.io.wkt.Convention#INTERNAL debugging purposes};
+ * most GIS applications will instead be interested in the {@linkplain
#getContextualParameters()
+ * contextual parameters} instead.
+ *
+ * @return the parameter values for this math transform.
+ */
+ @Debug
+ @Override
+ public ParameterValueGroup getParameterValues() {
+ final ParameterValueGroup values =
getParameterDescriptors().createValue();
+ values.values().add(context.values().get(0)); // First
parameter is grid pole latitude.
+ return values;
+ }
+
+ /**
+ * Returns the parameters used for creating the complete operation. The
returned group contains not only
+ * the grid pole latitude (which is handled by this transform), but also
the grid pole longitude and the
+ * grid angle of rotation (which are handled by affine transforms before
or after this transform).
+ *
+ * @return the parameter values for the sequence of <cite>normalize</cite>
→
+ * {@code this} → <cite>denormalize</cite> transforms.
+ */
+ @Override
+ protected ContextualParameters getContextualParameters() {
+ return context;
+ }
+
+ /**
+ * Transforms a single coordinate point in an array,
+ * and optionally computes the transform derivative at that location.
+ */
+ @Override
+ public Matrix transform(final double[] srcPts, final int srcOff,
+ final double[] dstPts, final int dstOff,
+ final boolean derivate) throws TransformException
+ {
+ /*
+ * Convert latitude and longitude coordinates to (x,y,z) Cartesian
coordinates on a sphere of radius 1.
+ * Note that the rotation around the Z axis has been performed in
geographic coordinates by the affine
+ * transform pre-concatenated to this transform, simply by subtracting
λp from the longitude value.
+ * This is simpler than performing the rotation in Cartesian
coordinates.
+ */
+ double λ = srcPts[srcOff];
+ double φ = srcPts[srcOff+1];
+ double z = sin(φ);
+ double cosφ = cos(φ);
+ double y = sin(λ) * cosφ;
+ double x = cos(λ) * cosφ;
+ /*
+ * Apply the rotation around Y axis (so the y value stay unchanged)
+ * and convert back to spherical coordinates.
+ */
+ double xr = cosθp * z - sinθp * x;
+ double zr = -cosθp * x - sinθp * z;
+ double R = sqrt(xr*xr + y*y); // The slower hypot(…) is not
needed because values are close to 1.
+ dstPts[dstOff] = atan2(y, xr);
+ dstPts[dstOff+1] = atan2(zr, R);
+ if (!derivate) {
+ return null;
+ }
+ throw new TransformException(); // TODO
+ }
+
+ /**
+ * Returns the inverse transform of this object.
+ *
+ * @return the inverse of this transform.
+ */
+ @Override
+ public synchronized MathTransform2D inverse() {
+ if (inverse == null) {
+ inverse = new RotatedPole(this);
+ }
+ return inverse;
+ }
+
+ /**
+ * Compares the specified object with this math transform for equality.
+ *
+ * @param object the object to compare with this transform.
+ * @param mode the strictness level of the comparison.
+ * @return {@code true} if the given object is considered equals to this
math transform.
+ */
+ @Override
+ public boolean equals(final Object object, final ComparisonMode mode) {
+ if (super.equals(object, mode)) {
+ final RotatedPole other = (RotatedPole) object;
+ if (mode.isApproximate()) {
+ return Numerics.epsilonEqual(sinθp, other.sinθp,
Formulas.ANGULAR_TOLERANCE * (PI/180)) &&
+ Numerics.epsilonEqual(cosθp, other.cosθp,
Formulas.ANGULAR_TOLERANCE * (PI/180));
+ } else {
+ return Numerics.equals(sinθp, other.sinθp) &&
+ Numerics.equals(cosθp, other.cosθp);
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Computes a hash value for this transform. This method is invoked by
{@link #hashCode()} when first needed.
+ */
+ @Override
+ protected int computeHashCode() {
+ return super.computeHashCode() + Double.hashCode(cosθp) +
Double.hashCode(sinθp);
+ }
+}
diff --git
a/core/sis-referencing/src/main/resources/META-INF/services/org.opengis.referencing.operation.OperationMethod
b/core/sis-referencing/src/main/resources/META-INF/services/org.opengis.referencing.operation.OperationMethod
index 429a260..2526f0e 100644
---
a/core/sis-referencing/src/main/resources/META-INF/services/org.opengis.referencing.operation.OperationMethod
+++
b/core/sis-referencing/src/main/resources/META-INF/services/org.opengis.referencing.operation.OperationMethod
@@ -63,6 +63,8 @@
org.apache.sis.internal.referencing.provider.ZonedTransverseMercator
org.apache.sis.internal.referencing.provider.Sinusoidal
org.apache.sis.internal.referencing.provider.Polyconic
org.apache.sis.internal.referencing.provider.Mollweide
+org.apache.sis.internal.referencing.provider.RotatedSouthPole
+org.apache.sis.internal.referencing.provider.RotatedNorthPole
org.apache.sis.internal.referencing.provider.NTv2
org.apache.sis.internal.referencing.provider.NTv1
org.apache.sis.internal.referencing.provider.NADCON
diff --git
a/core/sis-referencing/src/test/java/org/apache/sis/internal/referencing/provider/ProvidersTest.java
b/core/sis-referencing/src/test/java/org/apache/sis/internal/referencing/provider/ProvidersTest.java
index e3b4513..21351a0 100644
---
a/core/sis-referencing/src/test/java/org/apache/sis/internal/referencing/provider/ProvidersTest.java
+++
b/core/sis-referencing/src/test/java/org/apache/sis/internal/referencing/provider/ProvidersTest.java
@@ -36,7 +36,7 @@ import static org.junit.Assert.*;
* Tests {@link Providers} and some consistency rules of all providers defined
in this package.
*
* @author Martin Desruisseaux (Geomatys)
- * @version 1.1
+ * @version 1.2
* @since 0.6
* @module
*/
@@ -113,6 +113,8 @@ public final strictfp class ProvidersTest extends TestCase {
Sinusoidal.class,
Polyconic.class,
Mollweide.class,
+ RotatedSouthPole.class,
+ RotatedNorthPole.class,
NTv2.class,
NTv1.class,
NADCON.class,
diff --git
a/core/sis-referencing/src/test/java/org/apache/sis/referencing/operation/transform/RotatedPoleTest.java
b/core/sis-referencing/src/test/java/org/apache/sis/referencing/operation/transform/RotatedPoleTest.java
new file mode 100644
index 0000000..8cca70c
--- /dev/null
+++
b/core/sis-referencing/src/test/java/org/apache/sis/referencing/operation/transform/RotatedPoleTest.java
@@ -0,0 +1,118 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.sis.referencing.operation.transform;
+
+import org.junit.Test;
+import org.opengis.util.FactoryException;
+import org.opengis.parameter.ParameterValueGroup;
+import org.opengis.referencing.operation.MathTransformFactory;
+import org.opengis.referencing.operation.TransformException;
+import org.apache.sis.internal.referencing.Formulas;
+import org.apache.sis.parameter.Parameterized;
+import org.apache.sis.test.DependsOnMethod;
+
+
+/**
+ * Tests {@link RotatedPole}.
+ *
+ * @author Martin Desruisseaux (Geomatys)
+ * @version 1.2
+ * @since 1.2
+ * @module
+ */
+public final strictfp class RotatedPoleTest extends MathTransformTestCase {
+ /**
+ * Returns the transform factory to use for testing purpose.
+ * This mock supports only the "affine" and "concatenate" operations.
+ */
+ private static MathTransformFactory factory() {
+ return new MathTransformFactoryMock(null);
+ }
+
+ /**
+ * Creates a new transform which should be the inverse of current
transform according the
+ * parameters declared in {@link RotatedPole#context}. Those parameters
may be wrong even
+ * if the coordinates transformed by {@code transform.inverse()} are
corrects because the
+ * parameters are only for WKT formatting (they are not actually used for
transformation,
+ * unless we force their use as done in this method).
+ */
+ private void inverseSouthPoleTransform() throws FactoryException,
TransformException {
+ final ParameterValueGroup pg = ((Parameterized)
transform.inverse()).getParameterValues();
+ transform = RotatedPole.rotateSouthPole(factory(),
+ pg.parameter("grid_south_pole_longitude").doubleValue(),
+ pg.parameter("grid_south_pole_latitude") .doubleValue(),
+ pg.parameter("grid_south_pole_angle") .doubleValue());
+
+ }
+
+ /**
+ * Tests a rotation of south pole with the new pole on Greenwich.
+ * The {@link ucar.unidata.geoloc.LatLonPoint} class has been used
+ * as a reference implementation for computing the expected values.
+ *
+ * @throws FactoryException if the transform can not be created.
+ * @throws TransformException if an error occurred while transforming a
point.
+ */
+ @Test
+ public void testRotateSouthPoleOnGreenwich() throws FactoryException,
TransformException {
+ transform = RotatedPole.rotateSouthPole(factory(), 0, -60, 0);
+ tolerance = Formulas.ANGULAR_TOLERANCE;
+ isDerivativeSupported = false;
+ final double[] coordinates = { // (λ,φ) coordinates to convert.
+ 0, -51,
+ 20, -51,
+ 100, -61
+ };
+ final double[] expected = { // (λ,φ) coordinates after
conversion.
+ 0.000000000, -81.000000000,
+ 60.140453893, -75.629715301,
+ 136.900518716, -45.671868261
+ };
+ verifyTransform(coordinates, expected);
+ inverseSouthPoleTransform();
+ verifyTransform(expected, coordinates);
+ }
+
+ /**
+ * Tests a rotation of south pole with the pole on arbitrary meridian.
+ * The {@link ucar.unidata.geoloc.LatLonPoint} class has been used as
+ * a reference implementation for computing the expected values.
+ *
+ * @throws FactoryException if the transform can not be created.
+ * @throws TransformException if an error occurred while transforming a
point.
+ */
+ @Test
+ @DependsOnMethod("testRotateSouthPoleOnGreenwich")
+ public void testRotateSouthPoleWithAngle() throws FactoryException,
TransformException {
+ transform = RotatedPole.rotateSouthPole(factory(), 20, -50, 10);
+ tolerance = Formulas.ANGULAR_TOLERANCE;
+ isDerivativeSupported = false;
+ final double[] coordinates = { // (λ,φ) coordinates to convert.
+ 20, -51,
+ 80, -44,
+ -30, -89
+ };
+ final double[] expected = { // (λ,φ) coordinates after
conversion.
+ 170.000000000, -89.000000000,
+ 95.348788748, -49.758697265,
+ -188.792151374, -50.636582758
+ };
+ verifyTransform(coordinates, expected);
+ inverseSouthPoleTransform();
+ verifyTransform(expected, coordinates);
+ }
+}
diff --git
a/core/sis-referencing/src/test/java/org/apache/sis/test/suite/ReferencingTestSuite.java
b/core/sis-referencing/src/test/java/org/apache/sis/test/suite/ReferencingTestSuite.java
index 42130b8..412d597 100644
---
a/core/sis-referencing/src/test/java/org/apache/sis/test/suite/ReferencingTestSuite.java
+++
b/core/sis-referencing/src/test/java/org/apache/sis/test/suite/ReferencingTestSuite.java
@@ -142,6 +142,7 @@ import org.junit.BeforeClass;
org.apache.sis.referencing.operation.transform.EllipsoidToCentricTransformTest.class,
org.apache.sis.referencing.operation.transform.MolodenskyTransformTest.class,
org.apache.sis.referencing.operation.transform.AbridgedMolodenskyTransformTest.class,
+ org.apache.sis.referencing.operation.transform.RotatedPoleTest.class,
org.apache.sis.referencing.operation.transform.SphericalToCartesianTest.class,
org.apache.sis.referencing.operation.transform.CartesianToSphericalTest.class,
org.apache.sis.referencing.operation.transform.PolarToCartesianTest.class,
