Changeset 10383 for trunk/psLib

Timestamp:

Dec 1, 2006, 12:10:25 PM (20 years ago)

Author:

magnier

Message:

fixed sign errors : finally correct??

File:

• trunk/psLib/src/math/psEllipse.c (modified) (3 diffs)

trunk/psLib/src/math/psEllipse.c

@@ -14 +14 @@
     moments.x2 = +0.5*f1 + 0.5*f2*cos(2*axes.theta);
     moments.y2 = +0.5*f1 - 0.5*f2*cos(2*axes.theta);
-    moments.xy = -0.5*f2*sin(2*axes.theta);
+    moments.xy = +0.5*f2*sin(2*axes.theta);
 
     assert (isfinite(moments.x2));
@@ -33 +33 @@
 
     axes.major = sqrt (0.5*(g1 + g3));
-    axes.theta = 0.5 * atan2 (-2.0*moments.xy, g2); // theta in radians
+    axes.theta = +0.5 * atan2 (+2.0*moments.xy, g2); // theta in radians
 
     // long, thin objects are likely to have a poorly measured minor axis
@@ -84 +84 @@
 
     axes.minor = sqrt (2.0 / (f1 + f3));
-    axes.theta = 0.5 * atan2 (-2.0*shape.sxy, f2);
+    axes.theta = -0.5 * atan2 (+2.0*shape.sxy, f2);
 
     // long, thin objects are likely to have a poorly measured major axis