X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fpbd%2Fcartesian.cc;h=def1786c3ee89e91e8fdbf5ee8e49345642656e4;hb=a2b412803543e8892565bb96ccc091058a4f941f;hp=c5a1587b4c2618cda38d716f7fd17637536f6676;hpb=e50bd9e6530d6c708a4b259de6ef19e0fc6b97c0;p=ardour.git

diff --git a/libs/pbd/cartesian.cc b/libs/pbd/cartesian.cc
index c5a1587b4c..def1786c3e 100644
--- a/libs/pbd/cartesian.cc
+++ b/libs/pbd/cartesian.cc
@@ -16,56 +16,97 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 
-#include <cmath>
+#include <math.h>
+
 #include "pbd/cartesian.h"
 
+using namespace std;
+
 void
-PBD::azi_ele_to_cart (double azi, double ele, double& x, double& y, double& z)
+PBD::spherical_to_cartesian (double azi, double ele, double len, double& x, double& y, double& z)
 {
-        static const double atorad = 2.0 * M_PI / 360.0 ;
-        x = cos (azi * atorad) * cos (ele * atorad);
-        y = sin (azi * atorad) * cos (ele * atorad);
-        z = sin (ele * atorad);
+	/* convert from cylindrical coordinates in degrees to cartesian */
+
+	static const double atorad = 2.0 * M_PI / 360.0 ;
+        
+        if (len == 0.0) {
+                len = 1.0;
+        }
+
+	x = len * cos (azi * atorad) * cos (ele * atorad);
+	y = len * sin (azi * atorad) * cos (ele * atorad);
+	z = len * sin (ele * atorad);
 }
 
 void 
-PBD::cart_to_azi_ele (double x, double y, double z, double& azimuth, double& elevation)
+PBD::cartesian_to_spherical (double x, double y, double z, double& azimuth, double& elevation, double& length)
 {
-        /* converts cartesian coordinates to angular */
-        const double atorad = 2.0 * M_PI / 360.0;
-        double atan_y_per_x, atan_x_pl_y_per_z;
-        double distance;
+#if 1
+	/* converts cartesian coordinates to cylindrical in degrees*/
 
-        if(x == 0.0) {
-                atan_y_per_x = M_PI / 2;
-        } else {
-                atan_y_per_x = atan(y / x);
-        }
+        double rho, theta, phi;
 
-        azimuth = atan_y_per_x / atorad;
+        rho = sqrt (x*x + y*y + z*z);
+        phi = acos (1.0/rho);
+        theta = atan2 (y, x);
 
-        if (x < 0.0) {
-                azimuth +=180.0;
-        }
+        /* XXX for now, clamp phi to zero */
 
-        distance = sqrt (x*x + y*y);
+        phi = 0.0;
 
-        if (z == 0.0) {
-                atan_x_pl_y_per_z = 0.0;
+        if (theta < 0.0) {
+                azimuth = 180.0 - (180.0 * (theta / M_PI)); /* LHS is negative */
         } else {
-                atan_x_pl_y_per_z = atan (z/distance);
+                azimuth = 180.0 * (theta / M_PI);
         }
 
-        if (distance == 0.0) {
-                if (z < 0.0) {
-                        atan_x_pl_y_per_z = -M_PI/2.0;
-                } else {
-                        atan_x_pl_y_per_z = M_PI/2.0;
-                }
+        if (phi < 0.0) {
+                elevation = 180.0 - (180.0 * (phi / M_PI)); /* LHS is negative */
+        } else {
+                elevation = 180.0 * (phi /  M_PI);
         }
+        
+        length = rho;
+#else
+	/* converts cartesian coordinates to cylindrical in degrees*/
+
+	const double atorad = 2.0 * M_PI / 360.0;
+	double atan_y_per_x, atan_x_pl_y_per_z;
+	double distance;
+
+	if (x == 0.0) {
+		atan_y_per_x = M_PI / 2;
+	} else {
+		atan_y_per_x = atan2 (y,x);
+	}
+
+	if (y < 0.0) {
+		/* below x-axis: atan2 returns 0 .. -PI (negative) so convert to degrees and ADD to 180 */
+		azimuth = 180.0 + (atan_y_per_x / (M_PI/180.0) + 180.0);
+	} else {
+		/* above x-axis: atan2 returns 0 .. +PI so convert to degrees */
+		azimuth = atan_y_per_x / atorad;
+	}
+
+	distance = sqrt (x*x + y*y);
+
+	if (z == 0.0) {
+		atan_x_pl_y_per_z = 0.0;
+	} else {
+		atan_x_pl_y_per_z = atan2 (z,distance);
+	}
+
+	if (distance == 0.0) {
+		if (z < 0.0) {
+			atan_x_pl_y_per_z = -M_PI/2.0;
+		} else if (z > 0.0) {
+			atan_x_pl_y_per_z = M_PI/2.0;
+		}
+	}
 
-        elevation = atan_x_pl_y_per_z / atorad;
+	elevation = atan_x_pl_y_per_z / atorad;
 
-        // distance = sqrtf (x*x + y*y + z*z);
+	// distance = sqrtf (x*x + y*y + z*z);
+#endif
 }