Merge pull request #84 from jive/master

Avoid trying ConcatenatedTransform inverse for 3D to 2D downcast
geotools · Dec 17, 2012 · 0ba611c · 0ba611c
2 parents b166c21 + 47e837d
commit 0ba611c
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Showing 3 changed files with 66 additions and 3 deletions.
diff --git a/...rencing/src/test/java/org/geotools/referencing/operation/transform/MathTransformTest.java b/...rencing/src/test/java/org/geotools/referencing/operation/transform/MathTransformTest.java
@@ -33,6 +33,7 @@
 
 import org.geotools.geometry.DirectPosition1D;
 import org.geotools.geometry.GeneralDirectPosition;
+import org.geotools.referencing.CRS;
 import org.geotools.referencing.WKT;
 import org.geotools.referencing.ReferencingFactoryFinder;
 import org.geotools.referencing.crs.DefaultGeographicCRS;
@@ -573,4 +574,51 @@ private static void assertPointsEqual(final String   name,
             }
         }
     }
+
+    /**
+     * The following test case is similar to the transform constructed
+     * by Streaming Renderer to convert from 3D data to 2D data for display.
+     * <p>
+     * While the resulting {@link ConcatendatedTransform} works, it does
+     * not currently provide an inerse().
+     */
+    @Test
+    public void testWGS84toWGS843D() throws Exception {
+        String wkt = "GEOGCS[\"GDA94\","
+                + " DATUM[\"Geocentric Datum of Australia 1994\","
+                + "  SPHEROID[\"GRS 1980\", 6378137.0, 298.257222101, AUTHORITY[\"EPSG\",\"7019\"]],"
+                + "  TOWGS84[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], "
+                + " AUTHORITY[\"EPSG\",\"6283\"]], "
+                + " PRIMEM[\"Greenwich\", 0.0, AUTHORITY[\"EPSG\",\"8901\"]],"
+                + " UNIT[\"degree\", 0.017453292519943295], "
+                + " AXIS[\"Geodetic latitude\", NORTH], " + " AXIS[\"Geodetic longitude\", EAST], "
+                + " AXIS[\"Ellipsoidal height\", UP], " + " AUTHORITY[\"EPSG\",\"4939\"]]";
+        CoordinateReferenceSystem gda94 = CRS.parseWKT(wkt);
+        CoordinateReferenceSystem world = DefaultGeographicCRS.WGS84;
+
+        MathTransform toWgs84_3d = CRS.findMathTransform( gda94,  DefaultGeographicCRS.WGS84_3D );
+        MathTransform toWgs84_2d = CRS.findMathTransform( DefaultGeographicCRS.WGS84_3D, DefaultGeographicCRS.WGS84);
+        MathTransform transform = ConcatenatedTransform.create(toWgs84_3d, toWgs84_2d);
+        assertNotNull( transform );
+        assertEquals( 3, transform.getSourceDimensions() );
+        assertEquals( 2, transform.getTargetDimensions() );
+
+        // review transformation stages
+        ConcatenatedTransform concatenated = (ConcatenatedTransform) transform;
+        assertEquals( 3, concatenated.transform1.getSourceDimensions() );
+        assertEquals( 3, concatenated.transform1.getTargetDimensions() );
+        assertEquals( 3, concatenated.transform2.getSourceDimensions() );
+        assertEquals( 2, concatenated.transform2.getTargetDimensions() );
+        try {
+            MathTransform inverse = transform.inverse();
+            assertNotNull( inverse );
+            assertEquals( 2, inverse.getSourceDimensions() );
+            assertEquals( 3, inverse.getTargetDimensions() );
+            fail("Inverse of gda94 to WGS84 not expected to work at this time");
+        }
+        catch (NoninvertibleTransformException nope){
+            // expected
+        }
+
+    }
 }
diff --git a/modules/library/render/src/main/java/org/geotools/renderer/lite/StreamingRenderer.java b/modules/library/render/src/main/java/org/geotools/renderer/lite/StreamingRenderer.java
@@ -3273,8 +3273,23 @@ private LiteShape2 getTransformedShape(Geometry originalGeom, SymbolizerAssociat
                     Decimator d = getDecimator(sa.xform);
                     d.decimateTransformGeneralize(geom, sa.crsxform);
                     geom.geometryChanged();
-                    // then post process it (provide reverse transform if available)                   
-                    MathTransform reverse = sa.crsxform == null ? null : sa.crsxform.inverse();
+                    // then post process it (provide reverse transform if available)
+                    MathTransform reverse = null;
+                    if (sa.crsxform != null) {
+                        if (sa.crsxform instanceof ConcatenatedTransform
+                                && ((ConcatenatedTransform) sa.crsxform).transform1
+                                        .getTargetDimensions() >= 3
+                                && ((ConcatenatedTransform) sa.crsxform).transform2
+                                        .getTargetDimensions() == 2) {
+                            reverse = null; // We are downcasting 3D data to 2D data so no inverse is available
+                        } else {
+                            try {
+                                reverse = sa.crsxform.inverse();
+                            } catch (Exception cannotReverse) {
+                                reverse = null; // reverse transform not available
+                            }
+                        }
+                    }
                     geom = projectionHandler.postProcess(reverse, geom);
                     if(geom == null) {
                         shape = null;

diff --git a/modules/library/render/src/main/java/org/geotools/renderer/lite/SymbolizerAssociation.java b/modules/library/render/src/main/java/org/geotools/renderer/lite/SymbolizerAssociation.java
@@ -31,7 +31,7 @@
  */
 class SymbolizerAssociation{
     /**
-     * Full transform from data {@link #crs} through to viewport CRS followed throug
+     * Full transform from data {@link #crs} through to viewport CRS followed through
      * to the screen.
      */
      public MathTransform  xform = null;