/// <summary>
/// Change orientation of bubble surface or tube
/// </summary>
/// <param name="e">Event arguments</param>
private void ChangeLevelOrientation(DeviceOrientationChangedEventArgs e)
{
_bubbleSpeed = new Simple3DVector();
if (DeviceOrientationHelper.IsFlat(e.CurrentOrientation))
{
SurfaceShown = true;
DeviceOrientationInfo priorDoi = DeviceOrientationHelper.GetDeviceOrientationInfo(e.PreviousOrientation);
_bubblePosition = new Simple3DVector(priorDoi.NormalGravityVector.X, priorDoi.NormalGravityVector.Y, 0);
}
else
{
DeviceOrientationInfo doi = DeviceOrientationHelper.GetDeviceOrientationInfo(e.CurrentOrientation);
if (DeviceOrientationHelper.IsFlat(e.PreviousOrientation) || (e.PreviousOrientation == DeviceOrientation.Unknown))
{
MoveLevel.Angle = doi.AngleOnXYPlan;
_bubblePosition = new Simple3DVector();
SurfaceShown = false;
}
double accumulatedLoops = MoveLevel.Angle / 360;
accumulatedLoops = Math.Floor(accumulatedLoops + 0.5);
_tubeRotationAnimation.To = 360 * accumulatedLoops + doi.AngleOnXYPlan;
if ((_tubeRotationAnimation.To - MoveLevel.Angle) > 180)
{
_tubeRotationAnimation.To -= 360;
}
if ((_tubeRotationAnimation.To - MoveLevel.Angle) < -180)
{
_tubeRotationAnimation.To += 360;
}
_tubeRotationStoryboard.Begin();
_bubbleDirection = doi.HorizontalAxisPolarity;
}
_levelOrientation = e.CurrentOrientation;
}
/// <summary>
/// Update the tube level visuals
/// </summary>
private void UpdateTubeBubble(AccelerometerHelperReadingEventArgs e)
{
// ANGLE TEXT
// ----------
// Use filtered accelemeter data (st5ady)
double x = e.OptimallyFilteredAcceleration.X;
double y = e.OptimallyFilteredAcceleration.Y;
double horizontalAcceleration;
double verticalAcceleration;
// Choose appropriate axis based on orientation of level
horizontalAcceleration = _bubbleDirection * (DeviceOrientationHelper.IsPortrait(_levelOrientation) ? x : y);
verticalAcceleration = _bubbleDirection * (DeviceOrientationHelper.IsPortrait(_levelOrientation) ? y : -x); // rotate XY plan by -90
// Convert acceleration vector coordinates to Angles and Magnitude
// Update reading on screen of instant inclination assuming steady device (gravity = measured acceleration)
double magnitudeXYZ = e.OptimallyFilteredAcceleration.Magnitude;
double angle = 0.0;
if (magnitudeXYZ != 0.0)
{
angle = Math.Asin(horizontalAcceleration / magnitudeXYZ) * 180.0 / Math.PI;
}
_angle = angle;
// Display angles as if they were buoyancy force instead of gravity (opposite) since it is
// more natural to match targeted bubble location
_angleText = String.Format("{0:0.0}°", _angle);
// BUBBLE POSITION
// ---------------
// ----------------------------------------------------------
// For simplicity we are approximating that the bubble experiences a lateral attraction force
// proportional to the distance to its target location (top of the glass based on inclination).
// We will neglect the vertical speed of the bubble since the radius of the glass curve is much greater
// than the radius of radius of usable glass surface
// Assume tube curve has a 1m radius
// Destination position is x and y
// Current position is _bubblePosition.X (use only one dimension)
// Update Buoyancy
double lateralAcceleration = (horizontalAcceleration - _bubblePosition.X) * BuoyancyCoef * StandardGravityInMetric;
// Update drag:
double drag = _bubbleSpeed.X * (-ViscosityCoef);
// Update speed:
lateralAcceleration += drag;
lateralAcceleration /= AccelerometerRefreshRate; // impulse
_bubbleSpeed += new Simple3DVector(lateralAcceleration, 0, 0);
// Update position
_bubblePosition += (_bubbleSpeed / AccelerometerRefreshRate);
double edgeRadius = Math.Sin(EdgeGlassAngle);
// Get resulting direction and magnitude of bubble position given X
double magnitudeFlat = Math.Abs(_bubblePosition.X);
double direction = Math.Sign(_bubblePosition.X);
bool atEdge = false;
if (magnitudeFlat > edgeRadius)
{ // Bubble reaches the edge
magnitudeFlat = edgeRadius;
// lossy bouncing when reaching edges
// change direction
_bubbleSpeed *= -EdgeBouncingLossCoef;
// limit bubble position to edge
_bubblePosition = new Simple3DVector(magnitudeFlat * direction, 0, 0);
atEdge = true;
}
// Calculate position of bubble
MoveBubble.X = (_bubblePosition.X / edgeRadius) * ((UsableLateralAmplitude / 2) - (BubbleCanvas.Width / 4));
// Change bubble shape
double stretchRatio;
if (atEdge)
{
TubeBubbleSkew.AngleX = 0;
stretchRatio = 1.0 + (Math.Abs(Math.Sin(angle / 180.0 * Math.PI)) - Math.Sin(EdgeGlassAngle)) * AngleBasedTubeBubbleStrechingAtEdgeCoef;
TubeBubbleScale.ScaleX = 1.0 / stretchRatio;
TubeBubbleScale.ScaleY = SideWayBubbleAtEdgeBoostOnYAxis * stretchRatio;
}
else
{
double horizontalSpeed = Math.Abs(_bubbleSpeed.X);
double horizontalDirection = Math.Sign(_bubbleSpeed.X);
// Stretch is proportional to horizontal speed
stretchRatio = Math.Min(horizontalSpeed * SpeedBubbleStrechingCoef, MaximumBubbleXYStretchRatio - 1.0) + 1.0;
if (stretchRatio < MinimumStretchRatio)
{
stretchRatio = MinimumStretchRatio;
}
TubeBubbleSkew.AngleX = MaximumTubeBubbleSkew * (stretchRatio - 1.0) / (MaximumBubbleXYStretchRatio - 1.0) * horizontalDirection;
// Stretch is also proportional to buoyancy
stretchRatio -= TubeBubbleStretchBuoyancyCoef * ((verticalAcceleration / magnitudeXYZ) - MedianVerticalAcceleration);
if (stretchRatio < MinimumStretchRatio)
{
stretchRatio = MinimumStretchRatio;
}
TubeBubbleScale.ScaleX = 1.0 / stretchRatio;
TubeBubbleScale.ScaleY = MaximumBubbleXYStretchRatio * stretchRatio;
}
}
