void SaveLastKeyPressed(PhysicalKey key)
{
Handedness handedness = key.ParentSection.Handedness;
switch (handedness)
{
case Handedness.Left:
lastLeftKeyPressed = key;
timeOfLastLeftKeyPress = DateTime.Now;
if (timeOfLastRightKeyPress > timeOfLastAmbidextrousKeyPressed) // Both right-handed and left-handed keys have been pressed more recently than the last ambidextrous key was hit.
{
lastAmbidextrousKeyPressed = null;
}
break;
case Handedness.Right:
lastRightKeyPressed = key;
timeOfLastRightKeyPress = DateTime.Now;
if (timeOfLastLeftKeyPress > timeOfLastAmbidextrousKeyPressed) // Both right-handed and left-handed keys have been pressed more recently than the last ambidextrous key was hit.
{
lastAmbidextrousKeyPressed = null;
}
break;
case Handedness.Both:
lastAmbidextrousKeyPressed = key;
timeOfLastAmbidextrousKeyPressed = DateTime.Now;
break;
}
}
public double GetMouseToKeyboardTransitionCost(KeyDownEvent keyDownEvent)
{
PhysicalKey key = FindKey(keyDownEvent.Data);
if (key != null)
{
KeyboardSection parentSection = key.ParentSection;
if (parentSection.Handedness == Handedness.Right)
{
lastMouseHandedAction = ActionType.Keyboard;
if (MousePad == null)
{
throw new Exception("MousePad not specified.");
}
if (mousePadCenter.X == double.MinValue)
{
CalculateMousePadCenterPoint();
}
double travelDistance = MillerComplexity.GetDistance(parentSection.Center, mousePadCenter);
double targetApproachWidth = MillerComplexity.GetTargetApproachWidth(key.Size.Width, key.Size.Height);
return(MillerComplexity.GetTargetPressScore(travelDistance, targetApproachWidth));
}
}
return(0);
}
public void PrepareForAnalysis()
{
lastLeftKeyPressed = null;
lastRightKeyPressed = null;
lastAmbidextrousKeyPressed = null;
lastMouseHandedAction = ActionType.None;
}
double GetDistanceFromLastAmbidextrousKey(PhysicalKey key)
{
if (lastAmbidextrousKeyPressed == null)
{
return(double.MaxValue);
}
else
{
return(GetApproximateDistanceBetweenKeys(key, lastAmbidextrousKeyPressed));
}
}
double GetDistanceToLastRightHandedKey(PhysicalKey key)
{
if (lastRightKeyPressed == null)
{
return(GetApproximateDistanceToKey(homeKeysRight, key));
}
else
{
return(GetApproximateDistanceBetweenKeys(key, lastRightKeyPressed));
}
}
double CalculateCost(PhysicalKey key)
{
if (KeyIsARepeat(key))
{
return(MillerComplexity.GetCostOfRepeatHit(key.EffectiveTargetApproachWidth));
}
const double DBL_AverageDistanceToSpaceBarWhileHandsNearHomeKeys = 1.4; /* cm */
if (SpaceBarHitWhileHandsAtHomeRow(key))
{
return(MillerComplexity.GetTargetPressScore(DBL_AverageDistanceToSpaceBarWhileHandsNearHomeKeys, key.EffectiveTargetApproachWidth)); // Space bar hit and at least one hand is near the home key row position.
}
return(MillerComplexity.GetTargetPressScore(GetShortestDistanceToKey(key), key.EffectiveTargetApproachWidth));
}
public virtual double GetKeyCost(string keyName)
{
PhysicalKey key = FindKey(keyName);
double cost = 0;
if (key != null)
{
if (KeyHasSameHandednessAsMouse(key))
{
lastMouseHandedAction = ActionType.Keyboard;
}
cost = CalculateCost(key);
SaveLastKeyPressed(key);
}
else
{
//throw new Exception("key not found: " + keyName);
}
return(cost);
}
double GetShortestDistanceToKey(PhysicalKey key)
{
double distanceToLastSameHandedKey = double.MaxValue;
double distanceToAmbidextrousKey = GetDistanceFromLastAmbidextrousKey(key);
// Find the closest section (holding a previously-hit key) to the specified key...
if (key.ParentSection.Handedness == Handedness.Left)
{
distanceToLastSameHandedKey = GetDistanceToLastLeftHandedKey(key);
}
else if (key.ParentSection.Handedness == Handedness.Right)
{
distanceToLastSameHandedKey = GetDistanceToLastRightHandedKey(key);
}
else if (key.ParentSection.Handedness == Handedness.Both)
{
double distanceFromLastLeftHandedKey = GetDistanceToLastLeftHandedKey(key);
double distanceFromLastRightHandedKey = GetDistanceToLastRightHandedKey(key);
double distanceFromNearestHand = Math.Min(distanceToAmbidextrousKey, Math.Min(distanceFromLastLeftHandedKey, distanceFromLastRightHandedKey));
if (distanceFromNearestHand < double.MaxValue)
{
return(distanceFromNearestHand);
}
}
double smallestDistance;
if (distanceToLastSameHandedKey == double.MaxValue && distanceToAmbidextrousKey == double.MaxValue)
{
smallestDistance = DBL_MinimumDistanceBetweenKeys;
}
else
{
smallestDistance = Math.Min(distanceToLastSameHandedKey, distanceToAmbidextrousKey);
}
return(smallestDistance);
}
bool KeyHasSameHandednessAsMouse(PhysicalKey key)
{
return(key.ParentSection.Handedness == MousePadPosition);
}
bool SpaceBarHitWhileHandsAtHomeRow(PhysicalKey key)
{
return(key.Name == "Space" && (lastLeftKeyPressed == null || lastRightKeyPressed == null || lastLeftKeyPressed.ParentSection == homeKeysLeft || lastRightKeyPressed.ParentSection == homeKeysRight));
}
bool KeyIsARepeat(PhysicalKey key)
{
return(key == lastLeftKeyPressed || key == lastRightKeyPressed || key == lastAmbidextrousKeyPressed);
}
/// <summary>
/// Determines the approximate travel distance between keys by measuring the travel distance
/// between the parenting sections of the two keys.
/// </summary>
double GetApproximateDistanceBetweenKeys(PhysicalKey key1, PhysicalKey key2)
{
KeyboardSection section = key2.ParentSection;
return(GetApproximateDistanceToKey(section, key1));
}
/// <summary>
/// Returns the distance between the center of the specified section to the center of the section
/// holding the specified key.
/// </summary>
double GetApproximateDistanceToKey(KeyboardSection section, PhysicalKey key1)
{
double distanceBetweenPoints = GetDistanceBetweenPoints(key1.ParentSection.Center, section.Center);
return(Math.Max(distanceBetweenPoints, DBL_MinimumDistanceBetweenKeys));
}
