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desruisseaux pushed a commit to branch geoapi-4.0
in repository https://gitbox.apache.org/repos/asf/sis.git
commit 9dd1fc345bdca5c4ca3538d6144ca07cc867995c
Author: Martin Desruisseaux <martin.desruisse...@geomatys.com>
AuthorDate: Thu Feb 10 19:55:10 2022 +0100
Add GeoTIFF and PROJ names and identifiers for "Azimuthal Equidistant".
A verification in Snyder's book suggests that what other projects call
"Azimuthal Equidistant" is actually the "Modified Azimuthal Equidistant"
approximation (both were designed for islands in Micronesia).
Another source is https://cfconventions.org/wkt-proj-4.html
---
.../referencing/provider/ModifiedAzimuthalEquidistant.java | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git
a/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/ModifiedAzimuthalEquidistant.java
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/ModifiedAzimuthalEquidistant.java
index 3a9f92b..cf3c3c9 100644
---
a/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/ModifiedAzimuthalEquidistant.java
+++
b/core/sis-referencing/src/main/java/org/apache/sis/internal/referencing/provider/ModifiedAzimuthalEquidistant.java
@@ -29,8 +29,16 @@ import
org.apache.sis.referencing.operation.projection.NormalizedProjection;
/**
* The provider for <cite>"Modified Azimuthal Equidistant"</cite> projection
(EPSG:9832).
*
+ * <h2>Relationship with "Azimuthal Equidistant"</h2>
+ * The <cite>Modified Azimuthal Equidistant</cite> projection is an
approximation of a theoretically
+ * more generic oblique Azimuthal Equidistant projection. But Snyder's <u>Map
Projection — a working
+ * manual</u> book actually gives formulas for the same scope than the one
given by EPSG, namely for
+ * islands in Micronesia. Consequently we assume that what is commonly
presented by other libraries
+ * as a "generic" Azimuthal Equidistant projection is actually the Modified
Azimuthal Equidistant
+ * approximation.
+ *
* @author Martin Desruisseaux (Geomatys)
- * @version 1.1
+ * @version 1.2
*
* @see <a
href="http://geotiff.maptools.org/proj_list/azimuthal_equidistant.html";>GeoTIFF
parameters for Azimuthal Equidistant</a>
*
@@ -133,6 +141,9 @@ public final class ModifiedAzimuthalEquidistant extends
MapProjection {
PARAMETERS = builder.addIdentifier("9832")
.addName("Modified Azimuthal Equidistant")
+ .addName(Citations.GEOTIFF, "CT_AzimuthalEquidistant") //
See discussion in class javadoc.
+ .addName(Citations.PROJ4, "aeqd")
+ .addIdentifier(Citations.GEOTIFF, "12")
.createGroupForMapProjection(
LATITUDE_OF_ORIGIN,
LONGITUDE_OF_ORIGIN,
