JAL-3541 selectively merged build.gradle and gradle.properties

[jalview.git] / srcjar / fr / orsay / lri / varna / models / geom / MiscGeom.java

diff --git a/srcjar/fr/orsay/lri/varna/models/geom/MiscGeom.java b/srcjar/fr/orsay/lri/varna/models/geom/MiscGeom.java
new file mode 100644 (file)
index 0000000..ce3bc7d
--- /dev/null
+++ b/srcjar/fr/orsay/lri/varna/models/geom/MiscGeom.java
@@ -0,0 +1,34 @@
+/**
+ * File written by Raphael Champeimont
+ * UMR 7238 Genomique des Microorganismes
+ */
+package fr.orsay.lri.varna.models.geom;
+
+import java.awt.geom.Point2D;
+
+
+/**
+ * @author Raphael Champeimont
+ * Misc geometry functions.
+ */
+public class MiscGeom {
+
+       /**
+        * Compute the angle made by a vector.
+        */
+       public static double angleFromVector(Point2D.Double v) {
+               return MiscGeom.angleFromVector(v.x, v.y);
+       }
+
+       public static double angleFromVector(double x, double y) {
+               double l = Math.hypot(x, y);
+               if (y > 0) {
+                       return Math.acos(x / l);
+               } else if (y < 0) {
+                       return - Math.acos(x / l);
+               } else {
+                       return x > 0 ? 0 : Math.PI;
+               }
+       }
+
+}