diff --git a/LICENSE b/LICENSE
index f288702..e7f17fa 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,674 +1,21 @@
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-Program, unless a warranty or assumption of liability accompanies a
-copy of the Program in return for a fee.
-
- END OF TERMS AND CONDITIONS
-
- How to Apply These Terms to Your New Programs
-
- If you develop a new program, and you want it to be of the greatest
-possible use to the public, the best way to achieve this is to make it
-free software which everyone can redistribute and change under these terms.
-
- To do so, attach the following notices to the program. It is safest
-to attach them to the start of each source file to most effectively
-state the exclusion of warranty; and each file should have at least
-the "copyright" line and a pointer to where the full notice is found.
-
-
- Copyright (C)
-
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see .
-
-Also add information on how to contact you by electronic and paper mail.
-
- If the program does terminal interaction, make it output a short
-notice like this when it starts in an interactive mode:
-
- Copyright (C)
- This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
- This is free software, and you are welcome to redistribute it
- under certain conditions; type `show c' for details.
-
-The hypothetical commands `show w' and `show c' should show the appropriate
-parts of the General Public License. Of course, your program's commands
-might be different; for a GUI interface, you would use an "about box".
-
- You should also get your employer (if you work as a programmer) or school,
-if any, to sign a "copyright disclaimer" for the program, if necessary.
-For more information on this, and how to apply and follow the GNU GPL, see
-.
-
- The GNU General Public License does not permit incorporating your program
-into proprietary programs. If your program is a subroutine library, you
-may consider it more useful to permit linking proprietary applications with
-the library. If this is what you want to do, use the GNU Lesser General
-Public License instead of this License. But first, please read
-.
+MIT License
+
+Copyright (c) 2025 University College London
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/projects/AstroBalance/Assets/Scripts/RingBuffer.cs b/projects/AstroBalance/Assets/Scripts/RingBuffer.cs
deleted file mode 100644
index 91950b9..0000000
--- a/projects/AstroBalance/Assets/Scripts/RingBuffer.cs
+++ /dev/null
@@ -1,304 +0,0 @@
-#region License
-/* Copyright 2015 Joe Osborne
- *
- * This file is part of RingBuffer.
- *
- * RingBuffer is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * RingBuffer is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with RingBuffer. If not, see .
- */
-#endregion
-using System;
-using System.Collections;
-using System.Collections.Generic;
-
-namespace RingBuffer
-{
- ///
- /// A generic ring buffer with fixed capacity.
- ///
- /// The type of data stored in the buffer
- public class RingBuffer : IEnumerable, IEnumerable, ICollection, ICollection
- {
- protected int head = 0;
- protected int tail = 0;
- protected int size = 0;
-
- protected T[] buffer;
-
- private bool allowOverflow;
- public bool AllowOverflow
- {
- get { return allowOverflow; }
- }
-
- ///
- /// The total number of elements the buffer can store (grows).
- ///
- public int Capacity
- {
- get { return buffer.Length; }
- }
-
- ///
- /// The number of elements currently contained in the buffer.
- ///
- public int Size
- {
- get { return size; }
- }
-
- ///
- /// Retrieve the next item from the buffer.
- ///
- /// The oldest item added to the buffer.
- public T Get()
- {
- if (size == 0)
- throw new System.InvalidOperationException("Buffer is empty.");
- T _item = buffer[head];
- head = (head + 1) % Capacity;
- size--;
- return _item;
- }
-
- ///
- /// Adds an item to the end of the buffer.
- ///
- /// The item to be added.
- public void Put(T item)
- {
- // If tail & head are equal and the buffer is not empty, assume
- // that it will overflow and throw an exception.
- if (tail == head && size != 0)
- {
- if (allowOverflow)
- {
- addToBuffer(item, true);
- }
- else
- {
- throw new System.InvalidOperationException(
- "The RingBuffer is full"
- + ((byte)head).ToString()
- + ", "
- + ((byte)tail).ToString()
- );
- }
- }
- // If the buffer will not overflow, just add the item.
- else
- {
- addToBuffer(item, false);
- }
- }
-
- protected void addToBuffer(T toAdd, bool overflow)
- {
- if (overflow)
- {
- head = (head + 1) % Capacity;
- }
- else
- {
- size++;
- }
- buffer[tail] = toAdd;
- tail = (tail + 1) % Capacity;
- }
-
- #region Constructors
- // Default capacity is 4, default overflow behavior is false.
- public RingBuffer()
- : this(4) { }
-
- public RingBuffer(int capacity)
- : this(capacity, false) { }
-
- public RingBuffer(int capacity, bool overflow)
- {
- buffer = new T[capacity];
- allowOverflow = overflow;
- }
- #endregion
-
- #region IEnumerable Members
- public IEnumerator GetEnumerator()
- {
- int _index = head;
- for (int i = 0; i < size; i++, _index = (_index + 1) % Capacity)
- {
- yield return buffer[_index];
- }
- }
-
- IEnumerator IEnumerable.GetEnumerator()
- {
- return GetEnumerator();
- }
-
- IEnumerator IEnumerable.GetEnumerator()
- {
- return (IEnumerator)GetEnumerator();
- }
- #endregion
-
- #region ICollection Members
- public int Count
- {
- get { return size; }
- }
- public bool IsReadOnly
- {
- get { return false; }
- }
-
- public void Add(T item)
- {
- Put(item);
- }
-
- ///
- /// Determines whether the RingBuffer contains a specific value.
- ///
- /// The value to check the RingBuffer for.
- /// True if the RingBuffer contains
- /// , false if it does not.
- ///
- public bool Contains(T item)
- {
- EqualityComparer comparer = EqualityComparer.Default;
- int _index = head;
- for (int i = 0; i < size; i++, _index = (_index + 1) % Capacity)
- {
- if (comparer.Equals(item, buffer[_index]))
- return true;
- }
- return false;
- }
-
- ///
- /// Removes all items from the RingBuffer.
- ///
- public void Clear()
- {
- for (int i = 0; i < Capacity; i++)
- {
- buffer[i] = default(T);
- }
- head = 0;
- tail = 0;
- size = 0;
- }
-
- ///
- /// Copies the contents of the RingBuffer to
- /// starting at .
- ///
- /// The array to be copied to.
- /// The index of
- /// where the buffer should begin copying to.
- public void CopyTo(T[] array, int arrayIndex)
- {
- int _index = head;
- for (int i = 0; i < size; i++, arrayIndex++, _index = (_index + 1) % Capacity)
- {
- array[arrayIndex] = buffer[_index];
- }
- }
-
- ///
- /// Removes from the buffer.
- ///
- ///
- /// True if was found and
- /// successfully removed. False if was not
- /// found or there was a problem removing it from the RingBuffer.
- ///
- public bool Remove(T item)
- {
- int _index = head;
- int _removeIndex = 0;
- bool _foundItem = false;
- EqualityComparer _comparer = EqualityComparer.Default;
- for (int i = 0; i < size; i++, _index = (_index + 1) % Capacity)
- {
- if (_comparer.Equals(item, buffer[_index]))
- {
- _removeIndex = _index;
- _foundItem = true;
- break;
- }
- }
- if (_foundItem)
- {
- T[] _newBuffer = new T[size - 1];
- _index = head;
- bool _pastItem = false;
- for (int i = 0; i < size - 1; i++, _index = (_index + 1) % Capacity)
- {
- if (_index == _removeIndex)
- {
- _pastItem = true;
- }
- if (_pastItem)
- {
- _newBuffer[_index] = buffer[(_index + 1) % Capacity];
- }
- else
- {
- _newBuffer[_index] = buffer[_index];
- }
- }
- size--;
- buffer = _newBuffer;
- return true;
- }
- return false;
- }
- #endregion
-
- #region ICollection Members
- ///
- /// Gets an object that can be used to synchronize access to the
- /// RingBuffer.
- ///
- public Object SyncRoot
- {
- get { return this; }
- }
-
- ///
- /// Gets a value indicating whether access to the RingBuffer is
- /// synchronized (thread safe).
- ///
- public bool IsSynchronized
- {
- get { return false; }
- }
-
- ///
- /// Copies the elements of the RingBuffer to ,
- /// starting at a particular Array .
- ///
- /// The one-dimensional Array that is the
- /// destination of the elements copied from RingBuffer. The Array must
- /// have zero-based indexing.
- /// The zero-based index in
- /// at which copying begins.
- void ICollection.CopyTo(Array array, int index)
- {
- CopyTo((T[])array, index);
- }
- #endregion
- }
-}
diff --git a/projects/AstroBalance/Assets/Scripts/RingBuffer.cs.meta b/projects/AstroBalance/Assets/Scripts/RingBuffer.cs.meta
deleted file mode 100644
index ec335e9..0000000
--- a/projects/AstroBalance/Assets/Scripts/RingBuffer.cs.meta
+++ /dev/null
@@ -1,2 +0,0 @@
-fileFormatVersion: 2
-guid: b7010ae56bb9dfa49b21924e26e922b5
\ No newline at end of file
diff --git a/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchCode.cs b/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchCode.cs
index a8d82b6..f41ae70 100644
--- a/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchCode.cs
+++ b/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchCode.cs
@@ -1,7 +1,6 @@
using System.Collections.Generic;
using TMPro;
using Tobii.GameIntegration.Net;
-using TrackerBuffers;
using UnityEngine;
///
@@ -41,6 +40,7 @@ public class LaunchCode : MonoBehaviour
private float timeToSpriteChange;
private Sprite countDownSprite;
private GazeBuffer gazeBuffer;
+ private int minDataRequired = 2; // we need at least 2 data points to calculate steadiness.
void Start()
{
@@ -50,36 +50,37 @@ void Start()
countDownSprites.Remove(countDownSprite);
gameObject.GetComponent().sprite = countDownSprite;
timeToSpriteChange = timerDuration;
- gazeBuffer = new GazeBuffer(gazeBufferCapacity);
+ gazeBuffer = new GazeBuffer(gazeBufferCapacity, minDataRequired);
}
void Update()
{
- GazePoint gazePoint = new GazePoint();
+ GazeItem gazeItem = new GazeItem();
if (useMouseForTracker)
{
var mousePos = Input.mousePosition;
- gazePoint.X = mousePos.x;
- gazePoint.Y = mousePos.y;
- gazePoint.TimeStampMicroSeconds = (long)(Time.timeSinceLevelLoad * 1000000);
+ gazeItem.gazePoint.X = mousePos.x;
+ gazeItem.gazePoint.Y = mousePos.y;
+ gazeItem.gazePoint.TimeStampMicroSeconds = (long)(Time.timeSinceLevelLoad * 1000000);
}
else
{
- gazePoint = tracker.getGazePoint();
- Vector2 worldGaze = tracker.ConvertGazePointToWorldCoordinates(gazePoint);
- gazePoint.X = worldGaze.x;
- gazePoint.Y = worldGaze.y;
+ gazeItem.gazePoint = tracker.getGazePoint();
+ Vector2 worldGaze = tracker.ConvertGazePointToWorldCoordinates(gazeItem.gazePoint);
+ gazeItem.gazePoint.X = worldGaze.x;
+ gazeItem.gazePoint.Y = worldGaze.y;
}
- gazeBuffer.addIfNew(gazePoint);
+ gazeBuffer.addIfNew(gazeItem);
bool gazeIsSteady = false;
- GazePoint targetPoint = new GazePoint();
+ float targetX = 0f;
+ float targetY = 0f;
if (targetObject != null)
{
- targetPoint.X = targetObject.transform.position.x;
- targetPoint.Y = targetObject.transform.position.y;
- gazeIsSteady = gazeBuffer.gazeSteady(gazeTime, gazeTolerance, targetPoint);
+ targetX = targetObject.transform.position.x;
+ targetY = targetObject.transform.position.y;
+ gazeIsSteady = gazeBuffer.gazeSteady(gazeTime, gazeTolerance, targetX, targetY);
}
else
{
@@ -91,14 +92,14 @@ void Update()
string steadyText = gazeIsSteady ? "Gaze is steady" : "Gaze is not steady";
statusText.text =
"Look here -> "
- + targetPoint.X
+ + targetX
+ ", "
- + targetPoint.Y
+ + targetY
+ "\n"
+ "Looking here -> "
- + gazePoint.X
+ + gazeItem.gazePoint.X
+ ", "
- + gazePoint.Y
+ + gazeItem.gazePoint.Y
+ "\n"
+ steadyText;
}
diff --git a/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchControl.cs b/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchControl.cs
index bb78863..a2f51b5 100644
--- a/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchControl.cs
+++ b/projects/AstroBalance/Assets/Scripts/RocketLaunch/LaunchControl.cs
@@ -1,6 +1,5 @@
using TMPro;
using Tobii.GameIntegration.Net;
-using TrackerBuffers;
using UnityEngine;
///
@@ -48,10 +47,12 @@ public class LaunchControl : MonoBehaviour
private GameObject winScreen;
private TextMeshProUGUI winText;
- private HeadPoseBuffer headPoseBuffer;
+ private HeadAngleBuffer headPitchBuffer;
+ private HeadAngleBuffer headYawBuffer;
private bool usePitch; //true if we're using pitch speed, false if we're using yaw speed.
private RocketLaunchData gameData;
private float rocketSpeed;
+ private int minDataRequired = 2; // we need at least 2 data points to calculate a speed.
private string saveFilename = "RocketLaunchScores";
// Start is called once before the first execution of Update after the MonoBehaviour is created
@@ -61,7 +62,6 @@ void Start()
winText = winScreen.GetComponentInChildren();
winScreen.SetActive(false);
tracker = FindFirstObjectByType();
- headPoseBuffer = new HeadPoseBuffer(headPoseBufferCapacity);
SaveData saveData = new(saveFilename);
RocketLaunchData lastGameData = saveData.GetLastGameData();
@@ -74,7 +74,8 @@ void Start()
{
usePitch = !lastGameData.pitch;
}
-
+ headPitchBuffer = new HeadAngleBuffer(headPoseBufferCapacity, minDataRequired);
+ headYawBuffer = new HeadAngleBuffer(headPoseBufferCapacity, minDataRequired);
instructionsText.text = usePitch
? "Nod your head and repeat the code to launch the rocket!"
: "Shake your head and repeat the code to launch the rocket!";
@@ -116,12 +117,19 @@ void Update()
{
headPose = tracker.getHeadPose();
}
-
- headPoseBuffer.addIfNew(headPose);
-
- float headSpeed =
- headPoseBuffer.getSpeed(speedTime, usePitch)
- - headPoseBuffer.getSpeed(speedTime, !usePitch);
+ HeadPitchItem headPitch = new HeadPitchItem(headPose);
+ HeadYawItem headYaw = new HeadYawItem(headPose);
+ headPitchBuffer.addIfNew(headPitch);
+ headYawBuffer.addIfNew(headYaw);
+ float headSpeed = 0f;
+ if (usePitch)
+ {
+ headSpeed = headPitchBuffer.getSpeed(speedTime) - headYawBuffer.getSpeed(speedTime);
+ }
+ else
+ {
+ headSpeed = headYawBuffer.getSpeed(speedTime) - headPitchBuffer.getSpeed(speedTime);
+ }
headSpeed = Mathf.Max(0, headSpeed); // Clamp to zero to avoid negative speeds
if (statusText != null)
diff --git a/projects/AstroBalance/Assets/Scripts/TrackerBuffers.cs b/projects/AstroBalance/Assets/Scripts/TrackerBuffers.cs
index 8d6476e..568e212 100644
--- a/projects/AstroBalance/Assets/Scripts/TrackerBuffers.cs
+++ b/projects/AstroBalance/Assets/Scripts/TrackerBuffers.cs
@@ -1,296 +1,309 @@
using System;
+using System.Collections.Generic;
using System.Linq;
-using RingBuffer;
using Tobii.GameIntegration.Net;
-using UnityEngine;
-namespace TrackerBuffers
+///
+/// Holds a buffer for a head angle (pitch, yaw or roll).
+///
+class HeadAngleBuffer : TobiiBuffer
{
///
- /// Will hold the gazepoint buffer and provide methods to check gaze stability and direction.
+ /// Initializes a new instance of the HeadAngleBuffer class.
///
- /// TODO Understand how to make this thread safe.
- public class GazeBuffer : RingBuffer
+ /// The maximum number of items that can be stored in the buffer.
+ /// The minimum number of data points required to calculate a speed.
+ public HeadAngleBuffer(int capacity, int minDataRequired)
+ : base(capacity, minDataRequired) { }
+
+ ///
+ /// Calculates the average speed of the buffer over a given time period.
+ /// Speed is calculated as the average change in angle returned by GetAngle
+ /// Divided by the total change in time returned by TimeStampMicroSeconds
+ ///
+ /// The time period in seconds over which to calculate the average speed.
+ /// The average speed of the buffer over the given time period.
+ public float getSpeed(float speedTime)
{
- public GazeBuffer(int capacity)
- : base(capacity, true) { }
-
- ///
- /// Adds a new gaze point to the buffer if it has a different timestamp to the last added gaze point.
- /// returns true if the point was added, false otherwise.
- ///
- public bool addIfNew(GazePoint item)
- {
- if (
- size == 0
- || item.TimeStampMicroSeconds != buffer[getLatestEntryIndex()].TimeStampMicroSeconds
- )
- {
- base.Add(item);
- return true;
- }
- return false;
- }
+ float averageSpeed = 0f;
+ if (!hasEnoughData)
+ return averageSpeed;
- private int getLatestEntryIndex()
- {
- int last_entry = tail - 1;
- if (last_entry < 0)
- last_entry = size - 1;
- return last_entry;
- }
+ int timeInMicroseconds = (int)(speedTime * 1e6);
+ List headAngles = GetItems(timeInMicroseconds);
- ///
- /// returns true if the gaze points more recent than the time have a summed
- /// square distance from the target point less than the tolerance.
- ///
- /// in seconds to sample over
- /// the allowable range
- /// the target gaze point
- public bool gazeSteady(float time, float tolerance, GazePoint targetGazePoint)
- {
- if (size < 2)
- return false;
- int timeInMicroseconds = (int)(time * 1e6);
- CopyToTwoArrays(timeInMicroseconds, out float[] x_array, out float[] y_array);
- return gazeSteadyImpl(
- x_array,
- y_array,
- targetGazePoint.X,
- targetGazePoint.Y,
- tolerance
- );
- }
+ return calculateAverageSpeed(headAngles);
+ }
- ///
- /// returns true if the gaze points more recent than the time have a standard deviation
- /// less than the tolerance.
- ///
- /// in seconds to sample over
- /// the allowable standard deviation
- public bool gazeSteady(float time, float tolerance)
+ private float calculateAverageSpeed(List headAngles)
+ {
+ if (headAngles.Count() < 2)
{
- if (size < 2)
- return false;
- int timeInMicroseconds = (int)(time * 1e6);
- CopyToTwoArrays(timeInMicroseconds, out float[] x_array, out float[] y_array);
- float targetGazePointX = Queryable.Average(x_array.AsQueryable());
- float targetGazePointY = Queryable.Average(y_array.AsQueryable());
-
- return gazeSteadyImpl(x_array, y_array, targetGazePointX, targetGazePointY, tolerance);
+ return 0f;
}
-
- private bool gazeSteadyImpl(
- float[] x_array,
- float[] y_array,
- float targetGazePointX,
- float targetGazePointY,
- float tolerance
- )
+ float totalDistance = 0f;
+ for (int i = 0; i < headAngles.Count() - 1; i++)
{
- bool steady = false;
- float sumOfSquaresX = x_array
- .Select(val => (val - targetGazePointX) * (val - targetGazePointX))
- .Sum();
- float sumOfSquaresY = y_array
- .Select(val => (val - targetGazePointY) * (val - targetGazePointY))
- .Sum();
- float stddevX = (float)Math.Sqrt(sumOfSquaresX / x_array.Length);
- float stddevY = (float)Math.Sqrt(sumOfSquaresY / y_array.Length);
-
- if (stddevX < tolerance && stddevY < tolerance)
- steady = true;
-
- Debug.Log(
- "Gaze is "
- + steady
- + " at "
- + targetGazePointX
- + " "
- + targetGazePointY
- + "("
- + stddevX
- + ", "
- + stddevY
- + ")"
- + " Based on "
- + x_array.Length
- + " samples"
- );
- return steady;
+ totalDistance += Math.Abs(headAngles[i + 1].GetAngle() - headAngles[i].GetAngle());
}
- ///
- ///Copies the contents of the RingBuffer to two arrays,
- ///one for the x coordinates and one for the y, stopping
- /// when the timestamps are older than
- ///
- private void CopyToTwoArrays(long gazeTime, out float[] x_array, out float[] y_array)
- {
- if (size == 0)
- {
- x_array = new float[0];
- y_array = new float[0];
- return;
- }
- int _index = getLatestEntryIndex();
-
- int arrayIndex = 0;
- x_array = new float[size];
- y_array = new float[size];
- x_array[arrayIndex] = buffer[_index].X;
- y_array[arrayIndex] = buffer[_index].Y;
- long timestamp = buffer[_index].TimeStampMicroSeconds - gazeTime;
+ double totalTime =
+ (
+ headAngles[0].TimeStampMicroSeconds()
+ - headAngles[headAngles.Count() - 1].TimeStampMicroSeconds()
+ ) / 1e6;
+ float averageSpeed = (float)(totalDistance / totalTime);
- _index = _index > 0 ? _index - 1 : size - 1;
- arrayIndex++;
+ return averageSpeed;
+ }
+}
- while (_index != head && buffer[_index].TimeStampMicroSeconds >= timestamp)
- {
- x_array[arrayIndex] = buffer[_index].X;
- y_array[arrayIndex] = buffer[_index].Y;
- _index = _index > 0 ? _index - 1 : size - 1;
- arrayIndex++;
- }
- // Add head if it falls in time range
- if (size > 1 && _index == head && buffer[_index].TimeStampMicroSeconds >= timestamp)
- {
- x_array[arrayIndex] = buffer[_index].X;
- y_array[arrayIndex] = buffer[_index].Y;
- arrayIndex++;
- }
+///
+/// Holds the gazepoint buffer and provides a method to check gaze stability and direction.
+///
+class GazeBuffer : TobiiBuffer
+{
+ ///
+ /// Initializes a new instance of the GazeBuffer class.
+ ///
+ /// The maximum number of items that can be stored in the buffer.
+ /// The minimum number of data points required to calculate steadiness.
+ public GazeBuffer(int capacity, int minDataRequired)
+ : base(capacity, minDataRequired) { }
- Array.Resize(ref x_array, arrayIndex);
- Array.Resize(ref y_array, arrayIndex);
- }
+ ///
+ /// returns true if the data more recent than the time have a summed
+ /// square distance from the target point less than the tolerance.
+ ///
+ /// in seconds to sample over
+ /// the allowable range
+ /// x coordinate of the target point
+ /// y coordinate of the target point
+ public bool gazeSteady(float time, float tolerance, float targetPoint_x, float targetPoint_y)
+ {
+ if (!hasEnoughData)
+ return false;
+ int timeInMicroseconds = (int)(time * 1e6);
+ List gazePoints = GetItems(timeInMicroseconds);
+ GetXYArrays(gazePoints, out float[] array_x, out float[] array_y);
+ return dataSteadyImpl(array_x, array_y, targetPoint_x, targetPoint_y, tolerance);
}
- ///
- /// Will hold the HeadPose buffer and provide methods to check movement speed.
- /// TODO Understand how to make this thread safe.
- /// TODO I should be able to use inheritance to reduce duplication here, but
- /// had difficultly with templating.
+ //
+ /// returns true if the data more recent than the time have a standard deviation
+ /// less than the tolerance.
///
- public class HeadPoseBuffer : RingBuffer
+ /// in seconds to sample over
+ /// the allowable standard deviation
+ public bool gazeSteady(float time, float tolerance)
{
- public HeadPoseBuffer(int capacity)
- : base(capacity, true) { }
-
- ///
- /// Adds a new head pose to the buffer if it has a different timestamp to the last added head pose.
- /// Returns true if the point was added, false otherwise.
- ///
- public bool addIfNew(HeadPose item)
- {
- if (
- size == 0
- || item.TimeStampMicroSeconds != buffer[getLatestEntryIndex()].TimeStampMicroSeconds
- )
- {
- base.Add(item);
- return true;
- }
+ if (!hasEnoughData)
return false;
- }
+ int timeInMicroseconds = (int)(time * 1e6);
+ List gazePoints = GetItems(timeInMicroseconds);
+ GetXYArrays(gazePoints, out float[] array_x, out float[] array_y);
+ float targetPoint_x = Queryable.Average(array_x.AsQueryable());
+ float targetPoint_y = Queryable.Average(array_y.AsQueryable());
- ///
- /// Calculates the average speed of the head pose buffer over a given time period.
- ///
- /// The time period in seconds over which to calculate the average speed.
- /// Whether to use pitch in the calculation.
- /// The average speed of the head pose buffer over the given time period.
- public float getSpeed(float speedTime, bool usePitch)
+ return dataSteadyImpl(array_x, array_y, targetPoint_x, targetPoint_y, tolerance);
+ }
+
+ ///
+ /// Convert a list of gaze items into two arrays of x and y positions.
+ ///
+ /// The x array to fill
+ /// The y array to fill
+ private void GetXYArrays(List gazeItems, out float[] array_x, out float[] array_y)
+ {
+ array_x = new float[gazeItems.Count()];
+ array_y = new float[gazeItems.Count()];
+ for (int i = 0; i < gazeItems.Count(); i++)
{
- float averageSpeed = 0f;
- if (size < 2)
- return averageSpeed;
- int timeInMicroseconds = (int)(speedTime * 1e6);
- CopyToTwoArrays(
- timeInMicroseconds,
- usePitch,
- out float[] posArray,
- out float[] timeStampMicroSecondsArray
- );
+ array_x[i] = gazeItems[i].getX();
+ array_y[i] = gazeItems[i].getY();
+ }
+ }
- float totalDistance = 0f;
- for (int i = 0; i < posArray.Length - 1; i++)
- {
- totalDistance += Math.Abs(posArray[i + 1] - posArray[i]);
- }
+ private bool dataSteadyImpl(
+ float[] xPositions,
+ float[] yPositions,
+ float targetPointX,
+ float targetPointY,
+ float tolerance
+ )
+ {
+ bool steady = false;
+ float sumOfSquares_x = xPositions
+ .Select(val => (val - targetPointX) * (val - targetPointX))
+ .Sum();
+ float sumOfSquares_y = yPositions
+ .Select(val => (val - targetPointY) * (val - targetPointY))
+ .Sum();
+ float stddev_x = (float)Math.Sqrt(sumOfSquares_x / xPositions.Length);
+ float stddev_y = (float)Math.Sqrt(sumOfSquares_y / yPositions.Length);
- double totalTime =
- (timeStampMicroSecondsArray[0] - timeStampMicroSecondsArray[posArray.Length - 1])
- / 1e6;
- averageSpeed = (float)(totalDistance / totalTime);
- return averageSpeed;
- }
+ if (stddev_x < tolerance && stddev_y < tolerance)
+ steady = true;
+
+ return steady;
+ }
+}
- private int getLatestEntryIndex()
+/// define an interface for the buffer data to enable us to create templated buffers.
+interface ITimeStampMicroSeconds
+{
+ long TimeStampMicroSeconds();
+}
+
+///
+/// Wrapper for Tobii gazepoint data, implementing timestamp interface.
+///
+class GazeItem : ITimeStampMicroSeconds
+{
+ public GazePoint gazePoint;
+
+ public long TimeStampMicroSeconds() => gazePoint.TimeStampMicroSeconds;
+
+ public float getX() => gazePoint.X;
+
+ public float getY() => gazePoint.Y;
+}
+
+///
+/// Wrapper for Tobii headpose data, implementing timestamp interface.
+///
+abstract class HeadAngleItem : ITimeStampMicroSeconds
+{
+ protected HeadPose headPose;
+
+ public HeadAngleItem(HeadPose headPose)
+ {
+ this.headPose = headPose;
+ }
+
+ public long TimeStampMicroSeconds() => headPose.TimeStampMicroSeconds;
+
+ public abstract float GetAngle();
+}
+
+///
+/// Wrapper for Tobii head pose pitch data, returning pitch angle.
+///
+class HeadPitchItem : HeadAngleItem
+{
+ public HeadPitchItem(HeadPose headPose)
+ : base(headPose) { }
+
+ public override float GetAngle()
+ {
+ return headPose.Rotation.PitchDegrees;
+ }
+}
+
+///
+/// Wrapper for Tobii head pose yaw data, returning yaw angle.
+///
+class HeadYawItem : HeadAngleItem
+{
+ public HeadYawItem(HeadPose headPose)
+ : base(headPose) { }
+
+ public override float GetAngle()
+ {
+ return headPose.Rotation.YawDegrees;
+ }
+}
+
+///
+/// Base class for the tracker buffers, provides functionality to add items in a continuous loop, overwriting
+/// old data when the buffer is full.
+///
+class TobiiBuffer
+ where T : ITimeStampMicroSeconds
+{
+ protected int lastAddedIndex;
+ private bool hasData; // flag to indicate if the buffer has any data
+ protected bool hasEnoughData; // flag to indicate if the buffer has enough data to calculate speed or steadiness.
+ private int minDataRequired;
+ protected T[] buffer;
+
+ ///
+ /// Initializes a new instance of the class.
+ ///
+ /// The capacity of the buffer.
+ /// The minimum number of data points required for calculations to be meaningful.
+ public TobiiBuffer(int capacity, int minDataRequired)
+ {
+ if (capacity <= 0 || minDataRequired <= 0 || minDataRequired > capacity)
{
- int last_entry = tail - 1;
- if (last_entry < 0)
- last_entry = size - 1;
- return last_entry;
+ throw new ArgumentException(
+ "Capacity and minDataRequired must be positive and minDataRequired must be less than or equal to capacity."
+ );
}
+ buffer = new T[capacity];
+ lastAddedIndex = -1;
+ hasData = false;
+ hasEnoughData = false;
+ this.minDataRequired = minDataRequired;
+ }
- ///
- /// creates two arrays, one of positions and one of timestamps, from which we can
- /// calculate average speed. Positions can either be yaw, or pitch, switched
- /// by the value of usePitches
- ///
- /// The time period over which the speed is calculated
- /// Whether to use pitch or yaw
- /// The return array of positions
- /// The return array of timestamps
- private void CopyToTwoArrays(
- long speedTime,
- bool usePitches,
- out float[] pos_array,
- out float[] timestamp_array
+ ///
+ /// Adds a new item to the buffer if it has a different timestamp to the last added item.
+ /// returns true if the point was added, false otherwise.
+ ///
+ public bool addIfNew(T item)
+ {
+ if (
+ !hasData
+ || item.TimeStampMicroSeconds() != buffer[lastAddedIndex].TimeStampMicroSeconds()
)
{
- if (size == 0)
+ hasData = true;
+ int newIndex = lastAddedIndex + 1;
+ if (newIndex + 1 >= minDataRequired) // index starts at 0, so items added = newIndex + 1
{
- pos_array = new float[0];
- timestamp_array = new float[0];
- return;
+ hasEnoughData = true;
}
- int _index = getLatestEntryIndex();
+ if (newIndex >= buffer.Length)
+ {
+ newIndex = 0;
+ }
+ buffer[newIndex] = item;
+ lastAddedIndex = newIndex;
+ return true;
+ }
+ return false;
+ }
- int arrayIndex = 0;
- pos_array = new float[size];
- timestamp_array = new float[size];
+ ///
+ /// Return all items in the buffer created less than 'maximumAge' ago.
+ /// Items will be returned in order from newest to oldest.
+ ///
+ /// The maximum age (in microseconds) of the data to return.
+ protected List GetItems(long maximumAge)
+ {
+ List bufferItems = new List();
- pos_array[arrayIndex] = usePitches
- ? buffer[_index].Rotation.PitchDegrees
- : buffer[_index].Rotation.YawDegrees;
- timestamp_array[arrayIndex] = buffer[_index].TimeStampMicroSeconds;
- long timestamp = buffer[_index].TimeStampMicroSeconds - speedTime;
+ if (!hasData)
+ {
+ return bufferItems;
+ }
- _index = _index > 0 ? _index - 1 : size - 1;
- arrayIndex++;
+ int bufferIndex = lastAddedIndex;
+ bufferItems.Add(buffer[bufferIndex]);
+ long oldestAllowableTime = buffer[bufferIndex].TimeStampMicroSeconds() - maximumAge;
- while (_index != head && buffer[_index].TimeStampMicroSeconds >= timestamp)
- {
- pos_array[arrayIndex] = usePitches
- ? buffer[_index].Rotation.PitchDegrees
- : buffer[_index].Rotation.YawDegrees;
- timestamp_array[arrayIndex] = buffer[_index].TimeStampMicroSeconds;
- _index = _index > 0 ? _index - 1 : size - 1;
- arrayIndex++;
- }
- /// Add head if it falls in time range
- if (size > 1 && _index == head && buffer[_index].TimeStampMicroSeconds >= timestamp)
- {
- pos_array[arrayIndex] = usePitches
- ? buffer[_index].Rotation.PitchDegrees
- : buffer[_index].Rotation.YawDegrees;
- timestamp_array[arrayIndex] = buffer[_index].TimeStampMicroSeconds;
- arrayIndex++;
- }
+ bufferIndex = bufferIndex > 0 ? bufferIndex - 1 : buffer.Length - 1;
- Array.Resize(ref pos_array, arrayIndex);
- Array.Resize(ref timestamp_array, arrayIndex);
+ while (
+ bufferIndex != lastAddedIndex
+ && buffer[bufferIndex].TimeStampMicroSeconds() >= oldestAllowableTime
+ )
+ {
+ bufferItems.Add(buffer[bufferIndex]);
+ bufferIndex = bufferIndex > 0 ? bufferIndex - 1 : buffer.Length - 1;
}
+
+ return bufferItems;
}
}