/// <summary>
/// A recursive method which trace a ray until its power is less than ray-minimum power thershold
/// </summary>
/// <param name="path">New PathFromTxToRy object.</param>
/// <param name="ray">A starting ray (first ray)</param>
/// <param name="lastIntersectPart">A world object which this ray last intersect, or start</param>
/// <returns>PathFromTxToRy with True if it reaches receiver and False if it did not reach the receiver.</returns>
public PathFromTxToRy traceRay(PathFromTxToRy path, Ray ray, SceneObjectPart lastIntersectPart)
{
EntityIntersectionWithPart nextHit = findNextHit(ray, transmitter.RootPart);
if (nextHit.intersection.HitTF)
{
//Check for limit number of reflection allowed.
if(path.getNoOfReflection() >= MAX_REFLECTIONS)
{
path.reachesReceiver = false;
return path;
}
//drawRay(ray.Origin, nextHit.intersection.ipoint);
else if (nextHit.intersectPart.Equals(receiver.RootPart)) //If it reaches the receiver
{
path.reachesReceiver = true;
path.addNextPoint(nextHit.intersection.ipoint, receiver.RootPart.Material);
return path;
}//if
//recursive case, keep tracing this ray.
else
{
path.addNextPoint(nextHit.intersection.ipoint, nextHit.intersectPart.Material);
Vector3 reflectedVector = getReflectedVector(ray.Direction, nextHit.intersection.normal);
Ray newRay = new Ray(nextHit.intersection.ipoint, reflectedVector);
return traceRay(path, newRay, nextHit.intersectPart);
}//else if
}
else //It didn't hit anything
{
path.reachesReceiver = false;
return path;
}//else
}
/// <summary>
/// Draw a given path (A given path may contains many rays). This method just get all the ray in the
/// given path and draw them sequentially.
/// </summary>
/// <param name="path"></param>
public void drawRayPath(PathFromTxToRy path)
{
foreach(KeyValuePair<string, RayAsPathSection> ray in path.rayList)
{
//Note: Team KeyValuePair and Value are c# syntax for accessing dictionary element value and its key.
// To get the key, we do section.Key. To get the value we do section.Value;
string name = "ray_" + path.getNoOfReflection() + "_" + path.id + "_" + ray.Value.id;
drawRay(ray.Value.startPoint, ray.Value.endPoint, name);
}
}
public void getOneReflection()
{
int worldPartsSize = worldObjects.Count();
float toPercent = 100.0f / worldPartsSize;
float currentElementIndex = 1.0f;
Vector3 transmitterPos = transmitter.RootPart.AbsolutePosition;
Vector3 receiverPos = receiver.RootPart.AbsolutePosition;
//For each scenobjectpart, find the reflection point between the transmitter and the reciever.
foreach (SceneObjectPart part in worldObjects)
{
//Make sure that it doesn't reflect off the transmitter or the reciever
if (!part.Equals(transmitter.RootPart) && !part.Equals(receiver.RootPart))
{
//Check if the intersection point is found
ReflectionPoint reflectedPoint = findReflectionPoint(transmitterPos, receiverPos, part);
if (reflectedPoint.found)
{
string pathID = getPathID();
PathFromTxToRy newPath = new PathFromTxToRy(this, transmitter.RootPart.AbsolutePosition, pathID);
newPath.addNextPoint(reflectedPoint.reflectionPoint, reflectedPoint.surfaceMaterial);
newPath.addNextPoint(receiver.RootPart.AbsolutePosition, receiver.RootPart.Material);
newPath.reachesReceiver = true;
if (!checkPathIsDrawn(newPath))
{
pathHits[1].Add(pathID, newPath);
}//if
}//if
}//if
//Progress bar update
if (currentElementIndex < worldPartsSize)
{
updateProgressBar(currentElementIndex * toPercent);
}
else
{
updateProgressBar(100.0f);
}
currentElementIndex++;
}//forEachPart
}
public void getLineOfSight()
{
string pathID = getPathID();
PathFromTxToRy path = new PathFromTxToRy(this, transmitter.RootPart.AbsolutePosition, pathID);
//Direction from transmitter to the reciever
Vector3 direction = receiver.RootPart.AbsolutePosition - transmitter.RootPart.AbsolutePosition;
//Ray vector from transmitter to the receiver
Ray ray = new Ray(transmitter.RootPart.AbsolutePosition, direction);
//Get the first object the ray hit
EntityIntersectionWithPart intersection = findNextHit(ray, transmitter.RootPart);
path.addNextPoint(receiver.RootPart.AbsolutePosition, receiver.RootPart.Material);
path.reachesReceiver = true;
if (!checkPathIsDrawn(path))
{
pathHits[0].Add(pathID, path);
}
}
/// <summary>
/// From the transmitter, we create a ray in all direction (with angle between ray = ANGLE_BETWEEN_RAY). For each
/// of those ray, we 'trace/follow' them and find where they are heading. If they reaches the reciever, then
/// we store them in a list.
/// </summary>
public void startRayTracerBrutefoce()
{
m_log.DebugFormat("[BARE BONES NON SHARED] Started Raytracing!");
float lat, lon;
float toPercent = 100.0f/360.0f;
//For every lon and lat increase by ANGLE_BETWEEN_RAY
for (lon = 0; lon < 360; lon += ANGLE_BETWEEN_RAY)
{
for (lat = 0; lat < 360; lat += ANGLE_BETWEEN_RAY)
{
double lonr = lon * DEG_TO_RAD;
double latr = lat * DEG_TO_RAD;
//Note: Lat = angle of elevation. Lon = angle around the z-axis
//To get a point on a sphere using 2 angle
//Assuming Radius = 1 so we can get rid of multiplying radius.
//http://stackoverflow.com/questions/969798/plotting-a-point-on-the-edge-of-a-sphere
float x = (float)(Math.Sin(latr) * Math.Cos(lonr));
float y = (float)(Math.Sin(latr) * Math.Sin(lonr));
float z = (float)(Math.Cos(latr));
Vector3 pointOnSphere = new Vector3(x, y, z);
pointOnSphere.Normalize();
Vector3 direction = pointOnSphere;
Ray ray = new Ray(transmitter.RootPart.AbsolutePosition, direction);
//Trace this ray
string pathID = getPathID();
PathFromTxToRy thisRayPath = new PathFromTxToRy(this, transmitter.RootPart.AbsolutePosition, pathID);
thisRayPath = traceRay(thisRayPath, ray, transmitter.RootPart);
//If it reaches the receiver, then add it to the hit list.
if (thisRayPath.reachesReceiver && !checkPathIsDrawn(thisRayPath))
{
pathHits[thisRayPath.getNoOfReflection()].Add(pathID, thisRayPath);
}
}
//If lon < 359 then calculate the progress
if (lon < 359)
{
updateProgressBar(lon * toPercent);
}
else //else it is completed so return 100%
{
updateProgressBar(100.0f);
}
}//for
}
/// <summary>
/// Start a ray tracer from a given model. The model has 3 sections seperate by '//'
/// First section: Just says 'RTModel' to indicate that this is a ray tracer model
/// Second section: Variables section. This contians the variables which were set by the user
/// Third section: Set of paths from transmitter to the receiver.
/// </summary>
public void RayTraceFromModel(string givenModel, Scene _scene, UUID _scriptID)
{
string[] tokens = Regex.Split(givenModel, "//");
string section1 = tokens[0];
string section2 = tokens[1];
string section3 = tokens[2];
//Do a small check on the file. To make this better, we can do a checksum and keep it in here
//instead of 'RTModel'
if (section1 != "RTModel")
{
throw new Exception("The given ray trace model is not compatible");
}
Initialise(_scene, section2, _scriptID);
if (!sameTransmitter(section3))
{
throw new Exception("This model is invalid as the transmitter is moved");
}
//Each path is seperate by '#' so we split by '#' to get each path
//It only goes up to pathList.Length -1 because the last element is the empty string.
string[] pathList = section3.Split('#');
for(int i = 0; i < pathList.Length - 1; i++)
{
//Each position/point is seperate by '_' so we split path by '_'
//It only goes up to listOfPoints.Length -1 because the last element is the empty string.
string[] listOfPoints = pathList[i].Split('_');
//index 0 = starting point.
//Each coordinate (x, y, z) is seperate by ',' or we split this point by ','
string[] pointElements = listOfPoints[0].Split(',');
Vector3 currentPoint = new Vector3(float.Parse(pointElements[0]), float.Parse(pointElements[1]), float.Parse(pointElements[2]));
string pathID = getPathID();
PathFromTxToRy newPath = new PathFromTxToRy(this, currentPoint, pathID);
for(int j = 1; j < listOfPoints.Length - 1; j++)
{
pointElements = listOfPoints[j].Split(',');
currentPoint = new Vector3(float.Parse(pointElements[0]), float.Parse(pointElements[1]), float.Parse(pointElements[2]));
newPath.addNextPoint(currentPoint, float.Parse(pointElements[3]));
}
pathHits[newPath.getNoOfReflection()].Add(pathID, newPath);
}//for
RayTraceIsCalculated = true;
packAndSendGETMessages(false);
m_log.DebugFormat("[Finished Loaded a model]");
}
/// <summary>
/// There seems to be a bug that causes each path to be drawn twice. This function check, if the
/// given path has already been drawn. This function should be called everytime before adding a path
/// to a hit list.
/// </summary>
/// <param name="path"></param>
/// <returns>True = the path has already been drawn. False = the path hasn't been drawn</returns>
bool checkPathIsDrawn(PathFromTxToRy path)
{
Vector3 midPoint = new Vector3();
//To reduce the computation time, we only one ray from a path. i.e. break the loop when getting the first one.
foreach (KeyValuePair<string, RayAsPathSection> ray in path.rayList)
{
midPoint = ray.Value.endPoint - ray.Value.startPoint;
midPoint.X = Math.Abs(midPoint.X);
midPoint.Y = Math.Abs(midPoint.Y);
midPoint.Z = Math.Abs(midPoint.Z);
break;
}//foreach
//This loop will determine whether or not this path has been drawn before. It does this by
//compare the 'midPoint' against the list of other mid-points.
foreach (Vector3 pos in allRayPos)
{
if (pos.CompareTo(midPoint) == 0)
{
return true;
}//if
}//foreach
//Meaning that this path hasn't been drawm before. Add all of its ray's midpoint to the list
foreach (KeyValuePair<string, RayAsPathSection> ray in path.rayList)
{
Vector3 newRayPos = new Vector3();
newRayPos = ray.Value.endPoint - ray.Value.startPoint;
newRayPos.X = Math.Abs(newRayPos.X);
newRayPos.Y = Math.Abs(newRayPos.Y);
newRayPos.Z = Math.Abs(newRayPos.Z);
allRayPos.Add(newRayPos);
}//foreach
return false;
}
