--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-client/src/main/java/org/dive4elements/river/client/shared/Transform2D.java	Thu Apr 25 12:31:32 2013 +0200
@@ -0,0 +1,129 @@
+package de.intevation.flys.client.shared;
+
+import java.io.Serializable;
+import java.util.Date;
+
+import com.google.gwt.core.client.GWT;
+import com.google.gwt.i18n.client.DateTimeFormat;
+import com.google.gwt.i18n.client.DateTimeFormat.PredefinedFormat;
+import com.google.gwt.i18n.client.NumberFormat;
+
+
+/**
+ * This object supports a linear transformation to transform xy coordinates into
+ * an other coordinate system based on scale and translation values.
+ *
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public class Transform2D implements Serializable {
+
+    protected String xType;
+    protected String yType;
+
+    protected double sx;
+    protected double sy;
+
+    protected double tx;
+    protected double ty;
+
+
+    public Transform2D() {
+    }
+
+
+    /**
+     * Creates a new transformation with scale and translation factors.
+     *
+     * @param sx The scale factor for the x axis.
+     * @param sy The scale factor for the y axis.
+     * @param tx The translation factor for the x axis.
+     * @param ty The translation factor for the y axis.
+     */
+    public Transform2D(double sx, double sy, double tx, double ty) {
+        this(sx, sy, tx, ty, "number", "number");
+    }
+
+
+    public Transform2D(
+        double sx, double sy,
+        double tx, double ty,
+        String xType,
+        String yType
+    ) {
+        this.xType = xType;
+        this.yType = yType;
+
+        this.sx  = sx;
+        this.sy  = sy;
+        this.tx  = tx;
+        this.ty  = ty;
+    }
+
+
+    /**
+     * Transforms the pixel x and y into a new coordinate system based on the
+     * scale and translation values specified in the constructor.
+     */
+    public double[] transform(double x, double y) {
+        double resX = sx * x + tx;
+        double resY = sy * y + ty;
+
+        return new double[] { resX, resY };
+    }
+
+
+    public String[] format(Number[] xy) {
+        String x = null;
+        String y = null;
+
+        if (xType.equals("date")) {
+            x = formatDate(xy[0].longValue());
+        }
+        else {
+            x = formatNumber(xy[0].doubleValue());
+        }
+
+        if (yType.equals("date")) {
+            y = formatDate(xy[1].longValue());
+        }
+        else {
+            y = formatNumber(xy[1].doubleValue());
+        }
+
+        return new String[] { x, y };
+    }
+
+
+    protected String formatDate(long time) {
+        Date date = new Date(time);
+        DateTimeFormat df = getDateTimeFormat();
+
+        return df.format(date);
+    }
+
+
+    protected String formatNumber(double number) {
+        NumberFormat nf = getNumberFormat();
+
+        return nf.format(number);
+    }
+
+
+    public DateTimeFormat getDateTimeFormat() {
+        return DateTimeFormat.getFormat(PredefinedFormat.DATE_SHORT);
+    }
+
+
+    public NumberFormat getNumberFormat() {
+        return NumberFormat.getDecimalFormat();
+    }
+
+
+    public void dumpGWT() {
+        GWT.log("SX = " + sx);
+        GWT.log("SY = " + sy);
+        GWT.log("TX = " + tx);
+        GWT.log("TY = " + ty);
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :