Note revisions. Add licensing. Add supplemental information about project, algorithm, and algorithm lineage.

1 files changed, 48 insertions, 20 deletions

diff --git a/src/PJ_patterson.c b/src/PJ_patterson.c
index 0483bf6e..6fa10c28 100644
--- a/src/PJ_patterson.c
+++ b/src/PJ_patterson.c
@@ -1,17 +1,45 @@
 /*

- * The Patterson projection was designed by Tom Patterson, US National

+ * Copyright (c) 2014 Bojan Savric

+ * 

+ * Licensed 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.

+ */

+ 

+/*

+ * The Patterson Cylindrical projection was designed by Tom Patterson, US National

  * Park Service, in 2014, using Flex Projector. The polynomial equations for the

  * projection were developed by Bojan Savric, Oregon State University, in

  * collaboration with Tom Patterson and Bernhard Jenny, Oregon State University.

  *

- * Java reference algorithm implemented by Bojan Savric in JMapProjLib

- * project (file PattersonProjection.java)

+ * Java reference algorithm implemented by Bojan Savric in Java Map Projection

+ * Library (a Java port of PROJ.4) in the file PattersonProjection.java.

  *

- * Port to Proj.4 by Micah Cochran, 26 March 2016

+ * References:

+ *    Java Map Projection Library 

+ *       https://github.com/OSUCartography/JMapProjLib

+ * 

+ *    Patterson Cylindrical Projection

+ *       http://shadedrelief.com/patterson/

+ * 

+ *    Patterson, T., Savric, B., and Jenny, B. (2015). Cartographic Perspectives

+ *       (No.78). Describes the projection design and characteristics, and

+ *       developing the equations.    doi:10.14714/CP78.1270

+ *       http://dx.doi.org/10.14714/CP78.1270

+ * 

+ * Port to PROJ.4 by Micah Cochran, 26 March 2016

  */

 

 #define PJ_LIB__

-# include	<projects.h>

+# include   <projects.h>

 PROJ_HEAD(patterson, "Patterson Cylindrical") "\n\tCyl.";

 #define K1 1.0148

 #define K2 0.23185

@@ -26,15 +54,15 @@ PROJ_HEAD(patterson, "Patterson Cylindrical") "\n\tCyl.";
 

 FORWARD(s_forward); /* spheroid */

     double phi2;

-	(void) P;

+    (void) P;

     phi2 = lp.phi * lp.phi;

-	xy.x = lp.lam;

+    xy.x = lp.lam;

     xy.y = lp.phi * (K1 + phi2 * phi2 * (K2 + phi2 * (K3 + K4 * phi2)));

-	return (xy);

+    return (xy);

 }

 INVERSE(s_inverse); /* spheroid */

     double yc, tol, y2, f, fder;

-	(void) P;

+    (void) P;

     yc = xy.y;

     

     /* make sure y is inside valid range */

@@ -45,20 +73,20 @@ INVERSE(s_inverse); /* spheroid */
     }

     

     for (;;) { /* Newton-Raphson */

-		y2 = yc * yc;

-		f = (yc * (K1 + y2 * y2 * (K2 + y2 * (K3 + K4 * y2)))) - xy.y;

-		fder = C1 + y2 * y2 * (C2 + y2 * (C3 + C4 * y2));

-		yc -= tol = f / fder;

-		if (fabs(tol) < EPS11) {

-			break;

-		}

-	}

+        y2 = yc * yc;

+        f = (yc * (K1 + y2 * y2 * (K2 + y2 * (K3 + K4 * y2)))) - xy.y;

+        fder = C1 + y2 * y2 * (C2 + y2 * (C3 + C4 * y2));

+        yc -= tol = f / fder;

+        if (fabs(tol) < EPS11) {

+            break;

+        }

+    }

     lp.phi = yc;

     

     /* longitude */

-	lp.lam = xy.x;

-	

-	return (lp);

+    lp.lam = xy.x;

+    

+    return (lp);

 }

 FREEUP; if (P) pj_dalloc(P); }

 ENTRY0(patterson) P->es = 0.; P->inv = s_inverse; P->fwd = s_forward; ENDENTRY(P)