/**
* Determines whether point is within the object or on the surface
* @param point :: Point to be tested
* @returns true if point is within object or on surface
*/
bool MeshObject::isValid(const Kernel::V3D &point) const {
BoundingBox bb = getBoundingBox();
if (!bb.isPointInside(point)) {
return false;
}
Kernel::V3D direction(0.0, 0.0, 1.0); // direction to look for intersections
std::vector<Kernel::V3D> intersectionPoints;
std::vector<TrackDirection> entryExitFlags;
getIntersections(point, direction, intersectionPoints, entryExitFlags);
if (intersectionPoints.empty()) {
return false;
}
// True if point is on surface
for (const auto &intersectionPoint : intersectionPoints) {
if (point.distance(intersectionPoint) < M_TOLERANCE) {
return true;
}
}
// Look for nearest point then check its entry-exit flag
double nearestPointDistance = point.distance(intersectionPoints[0]);
size_t nearestPointIndex = 0;
for (size_t i = 1; i < intersectionPoints.size(); ++i) {
if (point.distance(intersectionPoints[i]) < nearestPointDistance) {
nearestPointDistance = point.distance(intersectionPoints[i]);
nearestPointIndex = i;
}
}
return (entryExitFlags[nearestPointIndex] == TrackDirection::LEAVING);
}
/**
* Determines wither point is on the surface.
* @param point :: Point to check
* @returns true if the point is on the surface
*/
bool MeshObject::isOnSide(const Kernel::V3D &point) const {
BoundingBox bb = getBoundingBox();
if (!bb.isPointInside(point)) {
return false;
}
const std::vector<Kernel::V3D> directions = {
Kernel::V3D{0, 0, 1}, Kernel::V3D{0, 1, 0},
Kernel::V3D{1, 0, 0}}; // directions to look for intersections
// We have to look in several directions in case a point is on a face
// or edge parallel to the first direction or also the second direction.
for (const auto &direction : directions) {
std::vector<Kernel::V3D> intersectionPoints;
std::vector<TrackDirection> entryExitFlags;
getIntersections(point, direction, intersectionPoints, entryExitFlags);
if (intersectionPoints.empty()) {
return false;
}
for (const auto &intersectionPoint : intersectionPoints) {
if (point.distance(intersectionPoint) < M_TOLERANCE) {
return true;
}
}
}
return false;
}
/**
* Given a track, fill the track with valid section
* @param UT :: Initial track
* @return Number of segments added
*/
int MeshObject::interceptSurface(Geometry::Track &UT) const {
int originalCount = UT.count(); // Number of intersections original track
BoundingBox bb = getBoundingBox();
if (!bb.doesLineIntersect(UT)) {
return 0;
}
std::vector<Kernel::V3D> intersectionPoints;
std::vector<TrackDirection> entryExit;
getIntersections(UT.startPoint(), UT.direction(), intersectionPoints,
entryExit);
if (intersectionPoints.empty())
return 0; // Quit if no intersections found
// For a 3D mesh, a ray may intersect several segments
for (size_t i = 0; i < intersectionPoints.size(); ++i) {
UT.addPoint(entryExit[i], intersectionPoints[i], *this);
}
UT.buildLink();
return UT.count() - originalCount;
}
Vector3d traceRay(Ray* ray, vector<SceneObject*>* objects, vector<SceneObject*>* lights, int remainingDepth) {
Vector3d backgroundColour(0, 0, 0);
Vector3d ambientLight(25, 25, 25);
/*Vector3d RED(255, 0, 0);
Vector3d GREEN(0, 255, 0);
Vector3d BLUE(255, 0, 255);
Vector3d YELLOW(255, 255, 0);
Vector3d CYAN(0, 255, 255);
Vector3d MAJENTA(255, 0, 255);*/
if (remainingDepth <= 0)
return backgroundColour;
vector<Intersection*>* intersections = getIntersections(objects, ray, NULL, false, (remainingDepth < 2));
Intersection* closestIntersection = getClosestIntersection(ray->origin, intersections);
Vector3d closestOrigin;
Vector3d closestDirection;
SceneObject* closestObject;
if (closestIntersection != NULL) {
closestOrigin = *(closestIntersection->origin);
closestDirection = *(closestIntersection->direction);
closestObject = closestIntersection->object;
}
freeIntersections(intersections);
intersections->clear();
delete intersections;
if (closestIntersection != NULL) {
Vector3d fullLightColour = ambientLight;
Vector3d surfaceColour = *(closestIntersection->object->colour);
//for each light, add it to the full light on this point (if not blocked)
for (unsigned int lightNum = 0; lightNum < lights->size(); lightNum++) {
SceneObject* light = (*lights)[lightNum];
Vector3d toLight = *(light->position) - closestOrigin;
Vector3d toLightNormalized = toLight.normalized();
double dot = toLightNormalized.dot(closestDirection);
if (dot > 0) {
intersections = getIntersections(objects, new Ray(&closestOrigin, &toLightNormalized), closestObject, true, false);
bool inLight = false;
if (intersections->size() == 0) {
inLight = true;
}
else {
Intersection* intersection = (*intersections)[0];
Vector3d intersectionOrigin = Vector3d(*(intersection->origin));
Vector3d intersectionDirection = Vector3d(*(intersection->direction));
SceneObject* obj = intersection->object;
if ((intersectionOrigin - closestOrigin).norm() > toLight.norm()) {
inLight = true;
}
}
if (inLight) {
fullLightColour += *(light->colour) * dot;
}
freeIntersections(intersections);
intersections->clear();
delete intersections;
}
}
double reflectivity = closestObject->reflectivity;
if (reflectivity > 0) {
Vector3d rayDirection = *(ray->direction);
Vector3d normal = closestDirection;
Vector3d reflectedDirection = rayDirection - ((2 * (normal.dot(rayDirection))) * normal);
Ray* reflectedRay = new Ray(&closestOrigin, &reflectedDirection);
Vector3d reflectionColour = traceRay(reflectedRay, objects, lights, remainingDepth - 1);
delete reflectedRay;
surfaceColour *= 1 - reflectivity;
surfaceColour += reflectionColour * reflectivity;
}
Vector3d endColour = surfaceColour;
endColour[0] *= fullLightColour[0] / 255;
endColour[1] *= fullLightColour[1] / 255;
endColour[2] *= fullLightColour[2] / 255;
return endColour;
}
else {
return backgroundColour;
}
}
