X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;f=srcjar%2Ffr%2Forsay%2Flri%2Fvarna%2Fmodels%2Fgeom%2FMiscGeom.java;fp=srcjar%2Ffr%2Forsay%2Flri%2Fvarna%2Fmodels%2Fgeom%2FMiscGeom.java;h=ce3bc7d46b079488e698689575cb6c713bcb612b;hb=2d6292c0377bc6b773c6844a45d3f2c5fac352c7;hp=0000000000000000000000000000000000000000;hpb=954af328a2a6a0055572cd1a09ee035301222574;p=jalview.git

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
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;
+		}
+	}
+
+}