/**
* Computes the point resulting from the intersection with another line
*
* @param otherLine the other line to apply the intersection. The lines are supposed
* to intersect
* @return point resulting from the intersection. If the point coundn't be obtained, return null
*/
public Point3d computeLineIntersection(Line otherLine)
{
//x = x1 + a1*t = x2 + b1*s
//y = y1 + a2*t = y2 + b2*s
//z = z1 + a3*t = z2 + b3*s
Point3d linePoint = otherLine.getPoint();
Vector3d lineDirection = otherLine.getDirection();
double t;
if (Math.Abs(direction.y * lineDirection.x - direction.x * lineDirection.y) > TOL)
{
t = (-point.y * lineDirection.x + linePoint.y * lineDirection.x + lineDirection.y * point.x - lineDirection.y * linePoint.x) / (direction.y * lineDirection.x - direction.x * lineDirection.y);
}
else if (Math.Abs(-direction.x * lineDirection.z + direction.z * lineDirection.x) > TOL)
{
t = -(-lineDirection.z * point.x + lineDirection.z * linePoint.x + lineDirection.x * point.z - lineDirection.x * linePoint.z) / (-direction.x * lineDirection.z + direction.z * lineDirection.x);
}
else if (Math.Abs(-direction.z * lineDirection.y + direction.y * lineDirection.z) > TOL)
{
t = (point.z * lineDirection.y - linePoint.z * lineDirection.y - lineDirection.z * point.y + lineDirection.z * linePoint.y) / (-direction.z * lineDirection.y + direction.y * lineDirection.z);
}
else
{
return(null);
}
double x = point.x + direction.x * t;
double y = point.y + direction.y * t;
double z = point.z + direction.z * t;
return(new Point3d(x, y, z));
}
/**
* Computes the point resulting from the intersection with another line
*
* @param otherLine the other line to apply the intersection. The lines are supposed
* to intersect
* @return point resulting from the intersection. If the point coundn't be obtained, return null
*/
public Point3d?computeLineIntersection(Line otherLine)
{
//x = x1 + a1*t = x2 + b1*s
//y = y1 + a2*t = y2 + b2*s
//z = z1 + a3*t = z2 + b3*s
Point3d linePoint = otherLine.getPoint();
Vector3d lineDirection = otherLine.getDirection();
float t;
if (Math.Abs(direction.Y * lineDirection.X - direction.X * lineDirection.Y) > TOL)
{
t = (-point.Y * lineDirection.X + linePoint.Y * lineDirection.X + lineDirection.Y * point.X - lineDirection.Y * linePoint.X) / (direction.Y * lineDirection.X - direction.X * lineDirection.Y);
}
else if (Math.Abs(-direction.X * lineDirection.Z + direction.Z * lineDirection.X) > TOL)
{
t = -(-lineDirection.Z * point.X + lineDirection.Z * linePoint.X + lineDirection.X * point.Z - lineDirection.X * linePoint.Z) / (-direction.X * lineDirection.Z + direction.Z * lineDirection.X);
}
else if (Math.Abs(-direction.Z * lineDirection.Y + direction.Y * lineDirection.Z) > TOL)
{
t = (point.Z * lineDirection.Y - linePoint.Z * lineDirection.Y - lineDirection.Z * point.Y + lineDirection.Z * linePoint.Y) / (-direction.Z * lineDirection.Y + direction.Y * lineDirection.Z);
}
else
{
return(null);
}
float x = point.X + direction.X * t;
float y = point.Y + direction.Y * t;
float z = point.Z + direction.Z * t;
return(new Point3d(x, y, z));
}
/**
* Classifies the face based on the ray trace technique
*
* @param object object3d used to compute the face status
*/
public void rayTraceClassify(Object3D obj)
{
//creating a ray starting starting at the face baricenter going to the normal direction
Point3d p0 = new Point3d();
p0.X = (v1.X + v2.X + v3.X) / 3.0f;
p0.Y = (v1.Y + v2.Y + v3.Y) / 3.0f;
p0.Z = (v1.Z + v2.Z + v3.Z) / 3.0f;
Line ray = new Line(getNormal(), p0);
bool success;
double dotProduct, distance;
Point3d?intersectionPoint;
Face closestFace = null;
double closestDistance;
do
{
success = true;
closestDistance = Double.MaxValue;
//for each face from the other solid...
for (int i = 0; i < obj.getNumFaces(); i++)
{
Face face = obj.getFace(i);
//dotProduct = face.getNormal().dot(ray.getDirection());
dotProduct = Vector3d.Dot(face.getNormal(), ray.getDirection());
intersectionPoint = ray.computePlaneIntersection(face.getNormal(), face.v1.getPosition());
//if ray intersects the plane...
if (intersectionPoint != null)
{
distance = ray.computePointToPointDistance(intersectionPoint.Value);
//if ray lies in plane...
if (Math.Abs(distance) < TOL && Math.Abs(dotProduct) < TOL)
{
//disturb the ray in order to not lie into another plane
ray.perturbDirection();
success = false;
break;
}
//if ray starts in plane...
if (Math.Abs(distance) < TOL && Math.Abs(dotProduct) > TOL)
{
//if ray intersects the face...
if (face.hasPoint(intersectionPoint.Value))
{
//faces coincide
closestFace = face;
closestDistance = 0;
break;
}
}
//if ray intersects plane...
else if (Math.Abs(dotProduct) > TOL && distance > TOL)
{
if (distance < closestDistance)
{
//if ray intersects the face;
if (face.hasPoint(intersectionPoint.Value))
{
//this face is the closest face untill now
closestDistance = distance;
closestFace = face;
}
}
}
}
}
} while (success == false);
//none face found: outside face
if (closestFace == null)
{
status = OUTSIDE;
}
//face found: test dot product
else
{
//dotProduct = closestFace.getNormal().dot(ray.getDirection());
dotProduct = Vector3d.Dot(closestFace.getNormal(), ray.getDirection());
//distance = 0: coplanar faces
if (Math.Abs(closestDistance) < TOL)
{
if (dotProduct > TOL)
{
status = SAME;
}
else if (dotProduct < -TOL)
{
status = OPPOSITE;
}
}
//dot product > 0 (same direction): inside face
else if (dotProduct > TOL)
{
status = INSIDE;
}
//dot product < 0 (opposite direction): outside face
else if (dotProduct < -TOL)
{
status = OUTSIDE;
}
}
}
/**
* Classifies the face based on the ray trace technique
*
* @param object object3d used to compute the face status
*/
public void rayTraceClassify(Object3D obj)
{
//creating a ray starting starting at the face baricenter going to the normal direction
Point3d p0 = new Point3d();
p0.x = (v1.x + v2.x + v3.x) / 3d;
p0.y = (v1.y + v2.y + v3.y) / 3d;
p0.z = (v1.z + v2.z + v3.z) / 3d;
Line ray = new Line(getNormal(), p0);
bool success;
double dotProduct, distance;
Point3d intersectionPoint;
Face closestFace = null;
double closestDistance;
do
{
success = true;
closestDistance = Double.MaxValue;
//for each face from the other solid...
for (int i = 0; i < obj.getNumFaces(); i++)
{
Face face = obj.getFace(i);
dotProduct = face.getNormal().dot(ray.getDirection());
intersectionPoint = ray.computePlaneIntersection(face.getNormal(), face.v1.getPosition());
//if ray intersects the plane...
if (intersectionPoint != null)
{
distance = ray.computePointToPointDistance(intersectionPoint);
//if ray lies in plane...
if (Math.Abs(distance) < TOL && Math.Abs(dotProduct) < TOL)
{
//disturb the ray in order to not lie into another plane
ray.perturbDirection();
success = false;
break;
}
//if ray starts in plane...
if (Math.Abs(distance) < TOL && Math.Abs(dotProduct) > TOL)
{
//if ray intersects the face...
if (face.hasPoint(intersectionPoint))
{
//faces coincide
closestFace = face;
closestDistance = 0;
break;
}
}
//if ray intersects plane...
else if (Math.Abs(dotProduct) > TOL && distance > TOL)
{
if (distance < closestDistance)
{
//if ray intersects the face;
if (face.hasPoint(intersectionPoint))
{
//this face is the closest face untill now
closestDistance = distance;
closestFace = face;
}
}
}
}
}
} while(success == false);
//none face found: outside face
if (closestFace == null)
{
status = OUTSIDE;
}
//face found: test dot product
else
{
dotProduct = closestFace.getNormal().dot(ray.getDirection());
//distance = 0: coplanar faces
if (Math.Abs(closestDistance) < TOL)
{
if (dotProduct > TOL)
{
status = SAME;
}
else if (dotProduct < -TOL)
{
status = OPPOSITE;
}
}
//dot product > 0 (same direction): inside face
else if (dotProduct > TOL)
{
status = INSIDE;
}
//dot product < 0 (opposite direction): outside face
else if (dotProduct < -TOL)
{
status = OUTSIDE;
}
}
}
/**
* Computes the point resulting from the intersection with another line
*
* @param otherLine the other line to apply the intersection. The lines are supposed
* to intersect
* @return point resulting from the intersection. If the point coundn't be obtained, return null
*/
public Point3d computeLineIntersection(Line otherLine)
{
//x = x1 + a1*t = x2 + b1*s
//y = y1 + a2*t = y2 + b2*s
//z = z1 + a3*t = z2 + b3*s
Point3d linePoint = otherLine.getPoint();
Vector3d lineDirection = otherLine.getDirection();
double t;
if (Math.Abs(direction.y * lineDirection.x - direction.x * lineDirection.y) > TOL)
{
t = (-point.y * lineDirection.x + linePoint.y * lineDirection.x + lineDirection.y * point.x - lineDirection.y * linePoint.x) / (direction.y * lineDirection.x - direction.x * lineDirection.y);
}
else if (Math.Abs(-direction.x * lineDirection.z + direction.z * lineDirection.x) > TOL)
{
t = -(-lineDirection.z * point.x + lineDirection.z * linePoint.x + lineDirection.x * point.z - lineDirection.x * linePoint.z) / (-direction.x * lineDirection.z + direction.z * lineDirection.x);
}
else if (Math.Abs(-direction.z * lineDirection.y + direction.y * lineDirection.z) > TOL)
{
t = (point.z * lineDirection.y - linePoint.z * lineDirection.y - lineDirection.z * point.y + lineDirection.z * linePoint.y) / (-direction.z * lineDirection.y + direction.y * lineDirection.z);
}
else
return null;
double x = point.x + direction.x * t;
double y = point.y + direction.y * t;
double z = point.z + direction.z * t;
return new Point3d(x, y, z);
}