/// <summary>
/// Apply Image Source Method (ISM) to calculate specular reflections
/// </summary>
void ISMUpdate()
{
// Clear old data
hitPaths.Clear();
System.Array.Clear(ir, 0, ir.Length);
// Check if the image source positions must be updated
if (SourceHasMoved() || renderSettings.IRUpdateRequested)
{
// Clear old image sources
imageSources.Clear();
// === E1: Add direct sound ===
// Add the original source to the image sources list
// (E1) YOUR CODE HERE
ImageSource OriginalSource = new ImageSource(transform.position);
imageSources.Add(OriginalSource);
// For each order of reflection
int i_end = 0;
for (var i_refl = 0;
i_refl < renderSettings.NumberOfISMReflections;
++i_refl)
{
// === E4: Higher order reflections ===
// (E4) YOUR CODE HERE: Update parent interval
int i_begin = 0;
i_end = imageSources.Count;
// i_end = ... Mathf.Min(1, imageSources.Count
// For each parent to reflect = i_begin; i_parent < i_end;
/* <-- (E4) YOUR CODE HERE: use i_begin and i_end to go through the parent image sources */
for (var i_parent = i_begin; i_parent < i_end; ++i_parent)
{
// === E2: Calculate image source positions ===
// Parent source on this iteration
ImageSource parentSource = imageSources[i_parent];
// For each mirroring plane
for (var i_child = 0;
i_child < renderSettings.PlaneCenters.Length;
++i_child)
{
// Get the current mirroring plane
Vector3 p_plane = renderSettings.PlaneCenters[i_child];
Vector3 n_plane = renderSettings.PlaneNormals[i_child];
// (E2) YOUR CODE HERE: calculate the distance from the plane to the source
Plane wall_plane = new Plane();
wall_plane.SetNormalAndPosition(n_plane, p_plane);
//Debug.Log(wall_plane.GetDistanceToPoint(transform.position));
float sourcePlaneDistance = wall_plane.GetDistanceToPoint(imageSources[i_parent].pos);
// Is the parent source in front of the plane?
if (sourcePlaneDistance > 0) /* <-- (E2) YOUR CODE HERE */
{
// Parent source is in front of the plane,
// calculate mirrored position
Vector3 mirroredPosition = imageSources[i_parent].pos + 2 * sourcePlaneDistance * (-n_plane);
// Add the image source
// (E2) YOUR CODE HERE
ImageSource IMGSource = new ImageSource(mirroredPosition, p_plane, n_plane, i_parent);
imageSources.Add(IMGSource);
}
}
}
}
}
// === E3: Cast rays ===
// A mask for game objects using ISMCollider (You define this "User Layer")
int ism_colliders_only = LayerMask.GetMask("ISM colliders");
// For each image source
for (var i = 0; i < imageSources.Count; ++i)
{
// Calculate path length
float pathLength = Vector3.Distance(imageSources[i].pos, ListenerPosition);/* <-- (E3) YOUR CODE HERE */
// Check that the path can contribute to the impulse response
if (pathLength < renderSettings.MaximumRayLength)
{
// Create a container for this path
RaycastHitPath path = new RaycastHitPath(pathLength);
// (E3) YOUR CODE HERE: Set the listener as the starting point for
// the ray
Vector3 origin = ListenerPosition;
//Debug.Log(ListenerPosition.x);
Vector3 originNormal = imageSources[i].pos - origin;
int i_next = i;
bool isValidPath = true;
// Loop until we have either processed the original source or
// found the path invalid
while (i_next != -1 && isValidPath)
{
// Get the current source
ImageSource imageSource = imageSources[i_next];
// (E3) YOUR CODE HERE: Determine ray direction and length
Vector3 dir = originNormal;
float max_length = Vector3.Distance(origin, imageSource.pos); //I OR I NEXT?
//Debug.Log(max_length);
// Trace the ray
RaycastHit hit;
//Physics.Raycast(origin, dir, out hit, max_length, ism_colliders_only);
Physics.Raycast(origin, dir, out hit, max_length);
//Debug.Log(hit.point);
//Debug.Log(hit.distance);
//Debug.Log(hit.collider);
if (imageSource.i_parent == -1)
{
// Handle the real source
// (E3) YOUR CODE HERE: check that the path is not obstructed
//if (Mathf.Abs(max_length - hit.distance) < 0.2)
if (Mathf.Abs(max_length - hit.distance) < 0.2)
{
isValidPath = true; //Physics.Raycast(origin, dir);
Debug.Log("path is not obstructed");
}
else
{
isValidPath = false;
Debug.Log("path is invalid");
}
}
else
{
// Handle image sources
// (E3) YOUR CODE HERE: check that the ray hits a wall on mirroring plane
isValidPath = ISMMath.PlaneEQ(hit, imageSource);
}
// (E3) Are there more checks needed? This depends on your previous implementation.
// Add the traced path if it is still valid
if (isValidPath)
{
// Path is valid, add the hit point to the ray path
// (E3) YOUR CODE HERE
path.points.Add(hit.point);
Debug.Log("path is valid, add hit point");
// Prepare to send the ray towards the next image source // it that okay?
origin = hit.point;
i_next = imageSource.i_parent;
//originNormal = imageSources[i_next].pos - origin;
if (i_next != -1)
{
originNormal = imageSources[i_next].pos - origin;
}
}
}
// Add the traced path if it is still valid
if (isValidPath)
{
// (E3) YOUR CODE HERE
Debug.Log("path added");
hitPaths.Add(path);
}
}
}
// === E5: create image source impulse response ===
foreach (var path in hitPaths)
{
// Calculate the sample that the ray path contributes to
int i_path = Mathf.RoundToInt(
AudioSettings.outputSampleRate * path.totalPathLength / ISMRenderSettings.speedOfSound); // <-- (E5) YOUR CODE HERE
if (i_path < ir.Length)
{
float abs = renderSettings.Absorption;
float diff = renderSettings.DiffuseProportion;
float num = path.points.Count;
float eps = Mathf.Pow(10, -6);
float p_ray = (Mathf.Pow((1 - abs) * (1 - diff), num / 2) / (path.totalPathLength + eps));
// (E5) YOUR CODE HERE: Determine the signal magnitude w.r.t.
// the amount of wall hits in the path
ir[i_path] += p_ray;
}
}
}
/// <summary>
/// Apply Image Source Method (ISM) to calculate specular reflections
/// </summary>
void ISMUpdate()
{
// Clear old data
hitPaths.Clear();
System.Array.Clear(ir, 0, ir.Length);
// Check if the image source positions must be updated
if (SourceHasMoved() || renderSettings.IRUpdateRequested)
{
// Clear old image sources
imageSources.Clear();
// === E1: Add direct sound ===
// (E1) YOUR CODE HERE
// Add the original source to the image sources list
imageSources.Add(new ImageSource(SourcePosition));
// For each order of reflection
int i_begin;
int i_end = 0;
for (var i_refl = 0; i_refl < renderSettings.NumberOfISMReflections; ++i_refl)
{
// === E4: Higher order reflections ===
// (E4) YOUR CODE HERE: Update parent interval
i_begin = i_end;
i_end = imageSources.Count;
// For each parent to reflect
for (var i_parent = i_begin; i_parent < i_end; ++i_parent) // <-- (E4) YOUR CODE HERE
{
// === E2: Calculate image source positions ===
// Parent source on this iteration
ImageSource parentSource = imageSources[i_parent];
// For each mirroring plane
for (var i_child = 0;
i_child < renderSettings.PlaneCenters.Length;
++i_child)
{
// Get the current mirroring plane
Vector3 p_plane = renderSettings.PlaneCenters[i_child];
Vector3 n_plane = renderSettings.PlaneNormals[i_child];
// (E2) YOUR CODE HERE: calculate the distance from the plane to the source
float sourcePlaneDistance = Vector3.Dot(parentSource.pos - p_plane, n_plane);
// Is the parent source in front of the plane?
if (sourcePlaneDistance > 0.0)
{
// Parent source is in front of the plane, calculate mirrored position
Vector3 N = transform.TransformDirection(n_plane);
Vector3 mirroredPosition = parentSource.pos - 2 * n_plane * sourcePlaneDistance;
// (E2) YOUR CODE HERE
// Add the image source
imageSources.Add(new ImageSource(mirroredPosition, p_plane, n_plane, i_parent));
}
}
}
}
}
// === E3: Cast rays ===
// A mask for game objects using ISMCollider
int ism_colliders_only = LayerMask.GetMask("ISM colliders");
// For each image source
for (var i = 0; i < imageSources.Count; ++i)
{
// Calculate path length
float pathLength = Vector3.Distance(imageSources[i].pos, ListenerPosition);
// Check that the path can contribute to the impulse response
if (pathLength < renderSettings.MaximumRayLength)
{
// Create a container for this path
RaycastHitPath path = new RaycastHitPath(pathLength);
// (E3) YOUR CODE HERE: Set the listener as the starting point for
// the ray
Vector3 origin = ListenerPosition;
Vector3 originNormal = imageSources[i].pos - origin;
int i_next = i;
bool isValidPath = true;
// Loop until we have either processed the original source or
// found the path invalid
while (i_next != -1 && isValidPath)
{
// Get the current source
ImageSource imageSource = imageSources[i_next];
// (E3) YOUR CODE HERE: Determine ray direction and length
Vector3 dir = originNormal;
float max_length = Vector3.Distance(origin, imageSource.pos);
// Trace the ray
RaycastHit hit;
// First, check that the outgoing ray is reflected from the wall
if (!Physics.Raycast(origin, dir, out hit, max_length, ism_colliders_only))
{
// The ray is sent in the wall, so the path is invalid
isValidPath = false;
}
else if (imageSource.i_parent == -1)
{
// (E3) YOUR CODE HERE
// Handle the real source: check that the path is not obstructed
if (Mathf.Abs(max_length - hit.distance) < 0.2)
{
isValidPath = true;
}
else
{
isValidPath = false;
}
}
else
{
// Handle image sources
// (E3) YOUR CODE HERE: check that the ray hits a wall on mirroring plane
isValidPath = ISMMath.PlaneEQ(hit, imageSource);
}
// Add the traced path if it is still valid
if (isValidPath)
{
// Path is valid, add the hit point to the ray path
// (E3) YOUR CODE HERE
path.points.Add(hit.point);
// Prepare to send the ray towards the next image source
i_next = imageSource.i_parent;
origin = hit.point;
if (i_next != -1)
{
originNormal = imageSources[i_next].pos - origin;
}
}
}
// Add the traced path if it is still valid
if (isValidPath)
{
// (E3) YOUR CODE HERE
hitPaths.Add(path);
}
}
}
// === E5: create image source impulse response ===
foreach (var path in hitPaths)
{
// Calculate the sample that the ray path contributes to
int i_path = Mathf.RoundToInt( // <-- (E5) YOUR CODE HERE
AudioSettings.outputSampleRate * path.totalPathLength / ISMRenderSettings.speedOfSound
);
if (i_path < ir.Length)
{
// (E5) YOUR CODE HERE: Determine the signal magnitude w.r.t.
// the amount of wall hits in the path
ir[i_path] += Mathf.Pow(
(1 - renderSettings.Absorption) * (1 - renderSettings.DiffuseProportion),
path.points.Count / 2
) / (path.totalPathLength + float.Epsilon);
}
}
}
