/// <summary>
/// Adds a new gesture to library and then saves it to the xml.
/// The trick here is that we don't reload the newly saved xml.
/// It would have been a waste of resources. Instead, we just add
/// the new gesture to the list of gestures (the library).
/// </summary>
/// <param name="gesture">The gesture to add</param>
/// <returns>True if addition is succesful</returns>
public bool AddGesture(Gesture gesture)
{
// Create the xml node to add to the xml file
XmlElement rootElement = gestureLibrary.DocumentElement;
XmlElement gestureNode = gestureLibrary.CreateElement("gesture");
gestureNode.SetAttribute("name", gesture.Name);
foreach (Vector2 v in gesture.Points) {
XmlElement gesturePoint = gestureLibrary.CreateElement("point");
gesturePoint.SetAttribute("x", v.x.ToString());
gesturePoint.SetAttribute("y", v.y.ToString());
gestureNode.AppendChild(gesturePoint);
}
// Append the node to xml file contents
rootElement.AppendChild(gestureNode);
try {
// Add the new gesture to the list of gestures
this.Library.Add(gesture);
// Save the file if it is not the web player, because
// web player cannot have write permissions.
#if !UNITY_WEBPLAYER && !UNITY_EDITOR
FileTools.Write(persistentLibraryPath, gestureLibrary.OuterXml);
#elif UNITY_EDITOR && !UNITY_WEBPLAYER
FileTools.Write(resourcesPath, gestureLibrary.OuterXml);
#endif
return true;
} catch (Exception e) {
Debug.Log(e.Message);
return false;
}
}
/// <summary>
/// Gets the average distance between two gestures at a specified angle
/// </summary>
/// <param name="gesture">Gesture to compare to</param>
/// <param name="angle">The angle to rotate this gesture</param>
/// <returns>Distance between two gestures</returns>
public float GetDistanceAtAngle(Gesture gesture, float angle)
{
List<Vector2> newPoints = this.RotateBy(angle);
return Gesture.GetDistanceBetweenPaths(newPoints, gesture.Points);
}
/// <summary>
/// $1 algorithm works like this:
/// - Take a gesture: with any number of points
/// - Resample: so that it has exactly NUMBER_OF_POINTS number of points which are equidistant to each other
/// - Rotate: based on the indicative angle (angle between the centroid and the first point)
/// - Scale and translate: so that it can fit into a predefined sized square
/// - Find the most optimized angle by Golden Section Search so that it has the best score
///
/// Resampling, rotating, scaling and translating ensures that gestures are somewhat "more" similar. By doing these
/// operations, we make them easier to compare. After these operations, the distance between two gestures
/// (which is the average distance between each points: d = sum(d1, d2, ..., dn) / n) is calculated. The gesture
/// with the least distance is the result and this result is converted to a score between [0, 1].
///
/// To get the best score, each gesture is rotated to the best indicative angle which is found by using
/// Golden Section Search.
/// </summary>
/// <param name="gesture">Gesture to compare</param>
/// <param name="a">Negative angle range</param>
/// <param name="b">Positive angle range</param>
/// <param name="threshold">Angle precision</param>
/// <returns>Score</returns>
public float DollarOneAlgorithm(Gesture gesture, float a, float b, float threshold)
{
float x1 = this.PHI * a + (1f - this.PHI) * b;
float f1 = this.GetDistanceAtAngle(gesture, x1);
float x2 = (1f - this.PHI) * a + this.PHI * b;
float f2 = this.GetDistanceAtAngle(gesture, x2);
while (Mathf.Abs(b - a) > threshold) {
if (f1 < f2) {
b = x2;
x2 = x1;
f2 = f1;
x1 = this.PHI * a + (1f - this.PHI) * b;
f1 = this.GetDistanceAtAngle(gesture, x1);
} else {
a = x1;
x1 = x2;
f1 = f2;
x2 = (1f - this.PHI) * a + this.PHI * b;
f2 = this.GetDistanceAtAngle(gesture, x2);
}
}
return Mathf.Min(f1, f2);
}
/// <summary>
/// Loads the library from an XML file
/// </summary>
public void LoadLibrary()
{
// Uses the XML file in resources folder if it is webplayer or the editor.
string xmlContents = "";
string floatSeparator = CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator;
#if !UNITY_WEBPLAYER && !UNITY_EDITOR
xmlContents = FileTools.Read(persistentLibraryPath);
#else
xmlContents = Resources.Load<TextAsset>(libraryName).text;
#endif
gestureLibrary.LoadXml(xmlContents);
// Get "gesture" elements
XmlNodeList xmlGestureList = gestureLibrary.GetElementsByTagName("gesture");
// Parse "gesture" elements and add them to library
foreach (XmlNode xmlGestureNode in xmlGestureList) {
string gestureName = xmlGestureNode.Attributes.GetNamedItem("name").Value;
XmlNodeList xmlPoints = xmlGestureNode.ChildNodes;
List<Vector2> gesturePoints = new List<Vector2>();
foreach (XmlNode point in xmlPoints) {
Vector2 gesturePoint = new Vector2();
gesturePoint.x = (float)System.Convert.ToDouble(point.Attributes.GetNamedItem("x").Value.Replace(",", floatSeparator).Replace(".", floatSeparator));
gesturePoint.y = (float)System.Convert.ToDouble(point.Attributes.GetNamedItem("y").Value.Replace(",", floatSeparator).Replace(".", floatSeparator));
gesturePoints.Add(gesturePoint);
}
Gesture gesture = new Gesture(gesturePoints, gestureName);
library.Add(gesture);
}
}
private void OnClickRemoveGesture()
{
currentLibrary.Gestures.Remove(currentGesture);
currentGesture = null;
EditorUtility.SetDirty(currentLibrary);
}
private void DrawInstructions()
{
GUILayout.BeginHorizontal();
GUILayout.FlexibleSpace();
GUILayout.Label("Draw your gesture, enter a name in the text field and then click 'Add'");
GUILayout.FlexibleSpace();
GUILayout.EndHorizontal();
GUILayout.FlexibleSpace();
GUILayout.BeginHorizontal();
GUILayout.FlexibleSpace();
newGestureName = GUILayout.TextField(newGestureName, 32, GUILayout.Width(200));
GUILayout.FlexibleSpace();
GUILayout.EndHorizontal();
GUILayout.BeginHorizontal();
GUILayout.FlexibleSpace();
if (newGestureName == "")
{
GUI.enabled = false;
}
if (GUILayout.Button("Add", GUILayout.Width(100)))
{
Gesture g = new Gesture(points.ToArray(), newGestureName);
currentLibrary.Gestures.Add(g);
ClearGesture();
isAddingGesture = false;
EditorUtility.SetDirty(currentLibrary);
}
GUI.enabled = true;
if (points.Count == 0)
{
GUI.enabled = false;
}
if (GUILayout.Button("Clear", GUILayout.Width(100)))
{
ClearGesture();
EditorUtility.SetDirty(currentLibrary);
}
GUI.enabled = true;
if (GUILayout.Button("Cancel", GUILayout.Width(100)))
{
ClearGesture();
isAddingGesture = false;
EditorUtility.SetDirty(currentLibrary);
}
GUILayout.FlexibleSpace();
GUILayout.EndHorizontal();
}
public void SaveToLibraryGesture(Gesture gesture)
{
}
