/// <summary>
/// Calculates the axis-aligned bounding box of the static points
/// </summary>
void calcStaticCenterPoint()
{
if (pointsStatic.Length != 0)
{
staticCenter = PointTransform.GetBoxCenterPoint(pointsStatic);
}
}
/// <summary>
/// Calculates the axis-aligned bounding box of all points
/// </summary>
void calcFixedCenterPoint()
{
if (pointsAll.Length != 0)
{
fixedCenter = PointTransform.GetBoxCenterPoint(pointsAll);
}
}
/// <summary>
/// Calculates the angle against the x-axis of just one finger from the center point.
/// Since the centerpoint used is the fixed center point using just one finger gives you the
/// most reliable angle calculation for calculating angle changed. It's also a nice optimisation.
/// There is some edge cases where this is not ideal, but they are unlikely to be encountered
/// under normal usage.
/// </summary>
/// <param name="center">The center of the axis-aligned bounding box of all fingers</param>
/// <returns></returns>
float getAngle(PointF center)
{
if (this.Count == 0)
{
return(0f);
}
PointF pTouch = this.First().Value.TouchPoint;
return(PointTransform.GetAngle(center, pTouch));
}
/// <summary>
/// Calculates the distance of just one finger from the center point.
/// Since the centerpoint used is the fixed center point all fingers are roughly equidistant.
/// Since this is called every frame, this is a nice optimisation.
/// </summary>
/// <param name="center">The center of the axis-aligned bounding box of all fingers</param>
/// <returns></returns>
float getDistanceFromCenter(PointF center)
{
if (this.Count == 0)
{
return(0f);
}
PointF pTouch = this.First().Value.TouchPoint;
return(PointTransform.GetDistanceFromCenter(center, pTouch));
}
/// <summary>
/// Gets the average distance of the passed points from the center.
/// </summary>
/// <param name="center">Center to calculate distance from.</param>
/// <param name="points">Points to average distance for.</param>
/// <returns></returns>
public static float GetAvgDistanceFromCenter(PointF center, PointF[] points)
{
if (points.Length == 0)
{
return(0f);
}
float avgDist = 0f;
for (int i = 0; i < points.Length; i++)
{
PointF p = points[i];
avgDist += PointTransform.GetDistance(center, p);
}
avgDist /= points.Length;
return(avgDist);
}
/// <summary>
/// Returns the angle in degrees from the passed point in comparision
/// to the x-axis of the centerpoint passed.
/// </summary>
/// <param name="centerPoint">Center point for the x-axis to calculate the angle against.</param>
/// <param name="point">The point to compare against the x-axis.</param>
/// <returns>Degrees between the point and the center point.</returns>
public static float GetAngle(PointF centerPoint, PointF point)
{
return(ExtMaths.RadiansToDegrees(PointTransform.GetAngleRadiansTan(centerPoint, point)));
}
/// <summary>
/// Gets the distance of the passed point from the center.
/// </summary>
/// <param name="center">Center to calculate distance from.</param>
/// <param name="points">Point to distance for.</param>
/// <returns></returns>
public static float GetDistanceFromCenter(PointF center, PointF point)
{
float dist = PointTransform.GetDistance(center, point);
return(dist);
}