Version 1, September 2006

[GpsPrune.git] / tim / prune / data / Altitude.java

diff --git a/tim/prune/data/Altitude.java b/tim/prune/data/Altitude.java
new file mode 100644 (file)
index 0000000..73552ae
--- /dev/null
+++ b/tim/prune/data/Altitude.java
@@ -0,0 +1,113 @@
+package tim.prune.data;
+
+/**
+ * Class to hold an altitude and provide conversion functions
+ */
+public class Altitude
+{
+       private boolean _valid = false;
+       private int _value = 0;
+       private int _format = -1;
+       public static final int FORMAT_NONE   = -1;
+       public static final int FORMAT_METRES = 0;
+       public static final int FORMAT_FEET = 1;
+
+       private static final double CONVERT_FEET_TO_METRES = 0.3048;
+       private static final double CONVERT_METRES_TO_FEET = 3.28084;
+
+
+       /**
+        * Constructor
+        */
+       public Altitude(String inString, int inFormat)
+       {
+               if (inString != null && !inString.equals(""))
+               {
+                       try
+                       {
+                               _value = Integer.parseInt(inString.trim());
+                               _format = inFormat;
+                               _valid = true;
+                       }
+                       catch (NumberFormatException nfe) {}
+               }
+       }
+
+
+       /**
+        * Constructor
+        */
+       public Altitude(int inValue, int inFormat)
+       {
+               _value = inValue;
+               _format = inFormat;
+               _valid = true;
+       }
+
+
+       /**
+        * @return true if the value could be parsed
+        */
+       public boolean isValid()
+       {
+               return _valid;
+       }
+
+
+       /**
+        * @return raw value as int
+        */
+       public int getValue()
+       {
+               return _value;
+       }
+
+
+       /**
+        * @return format of number
+        */
+       public int getFormat()
+       {
+               return _format;
+       }
+
+
+       /**
+        * Get the altitude value in the specified format
+        * @param inFormat desired format, either FORMAT_METRES or FORMAT_FEET
+        * @return value as an int
+        */
+       public int getValue(int inFormat)
+       {
+               if (inFormat == _format)
+                       return _value;
+               if (inFormat == FORMAT_METRES)
+                       return (int) (_value * CONVERT_FEET_TO_METRES);
+               if (inFormat == FORMAT_FEET)
+                       return (int) (_value * CONVERT_METRES_TO_FEET);
+               return _value;
+       }
+
+
+       /**
+        * Interpolate a new Altitude object between the given ones
+        * @param inStart start altitude
+        * @param inEnd end altitude
+        * @param inIndex index of interpolated point
+        * @param inNumSteps number of steps to interpolate
+        * @return Interpolated Altitude object
+        */
+       public static Altitude interpolate(Altitude inStart, Altitude inEnd, int inIndex, int inNumSteps)
+       {
+               // Check if altitudes are valid
+               if (inStart == null || inEnd == null || !inStart.isValid() || !inEnd.isValid())
+                       return new Altitude(null, FORMAT_NONE);
+               // Use altitude format of first point
+               int altFormat = inStart.getFormat();
+               int startValue = inStart.getValue();
+               int endValue = inEnd.getValue(altFormat);
+               int newValue = startValue
+                       + (int) ((endValue - startValue) * 1.0 / (inNumSteps + 1) * (inIndex + 1));
+               return new Altitude(newValue, altFormat);
+       }
+}