boost::optional<Intersection> Triangle::intersect(Ray ray) {
Eigen::Vector3f s1 = ray.dir.cross(d2);
const float div = s1.dot(d1);
if(div <= 0) { // parallel or back
return boost::optional<Intersection>();
}
const float div_inv = 1 / div;
Eigen::Vector3f s = ray.org - p0;
const float a = s.dot(s1) * div_inv;
if(a < 0 || a > 1) {
return boost::optional<Intersection>();
}
Eigen::Vector3f s2 = s.cross(d1);
const float b = ray.dir.dot(s2) * div_inv;
if(b < 0 || a + b > 1) {
return boost::optional<Intersection>();
}
const float t = d2.dot(s2) * div_inv;
if(t < 0) {
return boost::optional<Intersection>();
}
return boost::optional<Intersection>(Intersection(
t,
ray.at(t),
normal,
(1 - a - b) * uv0 + a * uv1 + b * uv2,
(1 - a - b) * ir0 + a * ir1 + b * ir2,
attribute));
}
bool Triangle::intersect(const Ray &ray, Intersection &intersection) const
{
const double NdotRayDir = N.dot(ray.direction);
if (NdotRayDir < 0.000001 && NdotRayDir > -0.000001) // no hit
return false;
intersection.t = (D - N.dot(ray.origin)) / (NdotRayDir);
const Vector i = ray.at(intersection.t); // intersection point with plane
// for an edge p1<->p2, we check to see if the cross product of that edge
// vector (p2-p1) and the vector from p1 to the intersection point points
// in the same direction as the normal vector
if ((p2-p1).cross(i - p1).dot(N) >= 0 &&
(p3-p2).cross(i - p2).dot(N) >= 0 &&
(p1-p3).cross(i - p3).dot(N) >= 0)
{
// i is within the triangle
intersection.primitive = const_cast<Triangle*>(this);
if (NdotRayDir > 0)
intersection.normal = -N;
else
intersection.normal = N;
return true;
}
return false;
}
void fillConicalDiffGeom(Diff_Geom &dg, const Ray &r, float t, bool in) const{
Vector3D pt_inter = r.at(t);
Vector3D dNdx, dNdy;
Vector3D normal=computenormal(pt_inter);
Vector3D dPpdx, dPpdy;
r.propagateDifferentials(t, normal, dPpdx, dPpdy);
computenormalDifferential(pt_inter, dPpdx, dPpdy, dNdx, dNdy);
Vector3D dTdx, dTdy;
float u, v;
computeConicalTexInfo(pt_inter, normal, dPpdx, dPpdy, u, v, dTdx, dTdy);
dg = Diff_Geom(pt_inter, normal, dNdx, dNdy, t, dPpdx, dPpdy, r.dDdx(), r.dDdy(), u, v, dTdx, dTdy, in);
}
void EntitiesEditor::computeCursor(int2 start, int2 end, bool floor_mode) {
float2 height_off = worldToScreen(int3(0, 0, 0));
start += m_view.pos();
end += m_view.pos();
Ray ray = screenRay(start);
Flags::Type flags = Flags::all;
if(floor_mode)
flags = flags & ~(Flags::wall_tile | Flags::object_tile);
auto isect = m_tile_map.trace(ray, -1, flags | Flags::visible);
float3 pos = isect.first == -1? (float3)asXZ(screenToWorld(start)) : ray.at(isect.second);
m_cursor_pos = (float3)round(pos);
m_selection = IRect(min(start, end), max(start, end));
}
Color Scene::trace(const Ray &ray)
{
// Find hit object and distance
Hit min_hit(std::numeric_limits<double>::infinity(),Vector());
Object *obj = NULL;
for (unsigned int i = 0; i < objects.size(); ++i) {
Hit hit(objects[i]->intersect(ray));
if (hit.t<min_hit.t) {
min_hit = hit;
obj = objects[i];
}
}
// No hit? Return background color.
if (!obj) return Color(0.0, 0.0, 0.0);
Material *material = obj->material; //the hit objects material
Point hit = ray.at(min_hit.t); //the hit point
Vector N = min_hit.N; //the normal at hit point
Vector V = -ray.D; //the view vector
/****************************************************
* This is where you should insert the color
* calculation (Phong model).
*
* Given: material, hit, N, V, lights[]
* Sought: color
*
* Hints: (see triple.h)
* Triple.dot(Vector) dot product
* Vector+Vector vector sum
* Vector-Vector vector difference
* Point-Point yields vector
* Vector.normalize() normalizes vector, returns length
* double*Color scales each color component (r,g,b)
* Color*Color dito
* pow(a,b) a to the power of b
****************************************************/
Color color = material->color; // place holder
return color;
}
bool Mesh::faceIntersection(
const Ray& ray, HitRecord* hitRecord, const Mesh::Face& face) {
// Get a point on the plane
Vector3D norm;
double t;
{
const auto& p0 = m_verts[face[0]];
const auto& p1 = m_verts[face[1]];
const auto& p2 = m_verts[face[face.size()-1]];
norm = (p1 - p0).cross(p2 - p0);
auto rayNorm = ray.dir.dot(norm);
// Parallel
if (isZero(rayNorm)) return false;
t = (p0 - ray.start).dot(norm) / rayNorm;
// No intersection
if (t < 0 || isZero(t)) {
return false;
}
}
// Intersection point
auto planePt = ray.at(t);
// Now check if planePt is "left" of everything
for (size_t i = 0; i < face.size(); ++i) {
// Go over points in order
const auto& p1 = m_verts[face[i]];
const auto& p2 = m_verts[face[(i + 1) % face.size()]];
// from p1 to p2
const auto side = p2 - p1;
// cross from p1 to plane pt and dot against normal
auto k = norm.dot(side.cross(planePt - p1));
if (!isZero(k) && k < 0) {
// Zero means on the side; negative means opposite dir from norm
return false;
}
}
// Update if this is a better t value
return hitRecord->update(norm, planePt, t);
}
bool Mesh::intersects(const Ray& ray,
HitRecord* hitRecord,
const Matrix4x4& inverseTransform) {
// New ray
const auto a = inverseTransform * ray.start;
const auto b = inverseTransform * ray.other;
const Ray newRay(a, b);
HitRecord boundingRecord;
HitRecord* boundingPtr;
if (BOUNDING_BOX_RENDER) {
boundingPtr = hitRecord;
}
else {
boundingPtr = &boundingRecord;
}
// First, check for intersection against our bounding box
if (!boundingCube.intersects(ray, boundingPtr, boundingCubeInverse * inverseTransform)) {
return false;
}
else if (BOUNDING_BOX_RENDER) {
return true;
}
// Note: This is not implemented correctly, since faceIntersection
// checks if the face was intersected *and* was a better t value
bool hit = false;
// For each polygon, check for polygon intersection lol...
for (const auto& face : m_faces) {
if (faceIntersection(newRay, hitRecord, face)) {
// haha, use real ray
hitRecord->point = ray.at(hitRecord->t);
hitRecord->norm = inverseTransform.transpose() * hitRecord->norm;
hitRecord->norm.normalize();
hit = true;
}
}
return hit;
}
bool Cylinder::intersects(const Ray& ray,
HitRecord* hitRecord,
const Matrix4x4& inverseTransform) const {
// New ray
const auto p1 = inverseTransform * ray.start;
const auto p2 = inverseTransform * ray.other;
const auto dir = p2 - p1;
double t = solveIntersection(p1, dir);
if (t < 0) return false;
auto localPoint = p1 + t * dir;
Vector3D localNorm(0, 0, 0);
if (isZero(localPoint[2] + 1)) {
localNorm = Vector3D(0, 0, -1);
}
else if (isZero(localPoint[2] - 1)) {
localNorm = Vector3D(0, 0, 1);
}
else {
// Not on one of the tops: Just like a circle
localNorm = Vector3D(localPoint[0], localPoint[1], 0);
}
// t is unchanged by this
// Remember to use the *original* intersection point
auto point = ray.at(t);
// To get the appropriate normal vector, we must also transpose
// the inverse transform
auto norm = inverseTransform.transpose() * localNorm;
norm.normalize();
// We will return whether or not this intersection was
// better than whatever was already stored there
return hitRecord->update(norm, point, t);
}
bool AABB::intersectsRay( const Ray& ray ) const
{
// if the start point OR the end point is in the AABB, then it's a hit.
// For the BOOLEAN check where you don't want the hit point, we use an OR (vs an AND)
bool rayStartInside = containsPoint( ray.start ) ;
if( rayStartInside || containsPoint( ray.end ) )
return true ; // I don't have to get you the exact point.
Vector3f t ;
if( rayStartInside )
for( int i = 0 ; i < 3 ; i++ )
if( ray.dir.elts[i] > 0 )
t.elts[i] = ( max.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
else
t.elts[i] = ( min.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
else
for( int i = 0 ; i < 3 ; i++ )
if( ray.dir.elts[i] > 0 )
t.elts[i] = ( min.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
else
t.elts[i] = ( max.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
int tIndex ;
if( rayStartInside ) tIndex = t.minIndex() ;
else tIndex = t.maxIndex() ;
if( isBetweenOrdered( t.elts[tIndex], 0, ray.len ) )
{
Vector3f pt = ray.at( t.elts[tIndex] ) ;
int o1 = OTHERAXIS1(tIndex) ;
int o2 = OTHERAXIS2(tIndex) ;
return isBetweenOrdered( pt.elts[o1], min.elts[o1], max.elts[o1] ) &&
isBetweenOrdered( pt.elts[o2], min.elts[o2], max.elts[o2] ) ;
}
return false ;
}
bool Triangle::doesIntersect (const Ray &ray) const
{
const double NdotRayDir = N.dot(ray.direction);
if (NdotRayDir < 0.000001 && NdotRayDir > -0.000001) // no hit
return false;
const double t = (D - N.dot(ray.origin)) / (NdotRayDir);
const Vector i = ray.at(t); // intersection point with plane
if (t < 0)
return false;
if ((p2-p1).cross(i - p1).dot(N) >= 0 &&
(p3-p2).cross(i - p2).dot(N) >= 0 &&
(p1-p3).cross(i - p3).dot(N) >= 0)
{
// i is within the triangle
return true;
}
return false;
}
bool Torus::intersects(const Ray& ray,
HitRecord* hitRecord,
const Matrix4x4& inverseTransform) const {
// New ray
const auto p1 = inverseTransform * ray.start;
const auto p2 = inverseTransform * ray.other;
Ray localRay(p1, p2);
double t = solveIntersection(localRay);
if (!isValid(t)) return false;
Point3D localPoint = localRay.at(t);
Point3D globalPoint = ray.at(t);
// Get the norm. See: http://www.emeyex.com/site/projects/raytorus.pdf
double k = Vector3D(localPoint).length2() - tubeRadius*tubeRadius - 1;
Vector3D localNorm(
4 * localPoint[0] * k,
4 * localPoint[1] * k,
4 * localPoint[2] * k + 8 * localPoint[2]
);
auto norm = inverseTransform.transpose() * localNorm;
norm.normalize();
return hitRecord->update(norm, globalPoint, t);
}
std::set<const Model*> UniformGrid::getModels(const Ray& ray) const {
std::set<const Model*> models;
Point3D nextT(0, 0, 0);
// The point *within* the grid where the ray first intersected it
Point3D rayStartPoint(0, 0, 0);
if (!inGrid(ray.start)) {
const auto& sp = startPoint;
// Not in the grid: We will use a cube the sz of whole grid to find
// the point of entry into the grid
auto gridCubeInverse = (translationMatrix(sp[0], sp[0], sp[0]) *
gridSizeScaleMatrix).invert();
HitRecord hr;
if (!utilityCube.intersects(ray, &hr, gridCubeInverse)) {
// Does not intersect the grid even
return models;
}
nextT[0] = hr.t;
nextT[1] = hr.t;
nextT[2] = hr.t;
rayStartPoint = ray.at(hr.t);
}
else {
rayStartPoint = ray.start;
}
// Place in the grid we are currently stepping through
CellCoord gridCoord = coordAt(rayStartPoint);
Vector3D dir(
std::abs(ray.dir[0]), std::abs(ray.dir[1]), std::abs(ray.dir[2]));
// These values are in units of t: how far we must go to travel a whole cell
Vector3D dt(
isZero(dir[0]) ? 0 : cellSize / dir[0],
isZero(dir[1]) ? 0 : cellSize / dir[1],
isZero(dir[2]) ? 0 : cellSize / dir[2]
);
{
// The bottom left corner of the cell we are starting in
Point3D gsp = pointAt(gridCoord); // "Grid start point"
// Determine how far, in units of t, we have to go in any direction
// to reach the next cell
// If we are going "forwards" in a coordinate then we need to travel to
// gsp + cellSize. If we are going "backwards" in a coordinate then we need
// to travel to only gsp.
for (int i = 0; i < 3; ++i) {
if (isZero(dir[i])) {
nextT[i] = -1;
continue;
}
if (ray.dir[i] < 0) {
nextT[i] += (rayStartPoint[i] - gsp[i]) / dir[i];
}
else {
nextT[i] += (gsp[i] + cellSize - rayStartPoint[i]) / dir[i];
}
}
}
// Which direction in the grid to move when we hit a "next" value
CellCoord incs(
(ray.dir[0] > 0) ? 1 : -1,
(ray.dir[1] > 0) ? 1 : -1,
(ray.dir[2] > 0) ? 1 : -1
);
// Check if a coord is still valid
auto coordOk = [&] (int coord) -> bool {
return 0 <= coord && coord < sideLength;
};
auto smaller = [] (double a, double b) -> bool {
return (b < 0) || a <= b;
};
while (coordOk(gridCoord.x) && coordOk(gridCoord.y) && coordOk(gridCoord.z)) {
for (const Model* model : cells[indexFor(gridCoord)].models) {
models.insert(model);
}
for (int i = 0; i < 3; ++i) {
if (nextT[i] < 0) continue;
const auto a = nextT[(i + 1) % 3];
const auto b = nextT[(i + 2) % 3];
if (smaller(nextT[i], a) && smaller(nextT[i], b)) {
nextT[i] += dt[i];
gridCoord[i] += incs[i];
break;
}
}
}
return models;
}
bool AABB::intersects( const Ray& ray, Vector& pt )
{
// Rays starting and ending in an octree node must be considered
// to hit the node.
// if the start point OR the end point is in the AABB, then it's a hit.
if( containsIn( ray.startPos ) || containsIn( ray.getEndPoint() ) )
{
//generateDebugLines( Vector(0,1,0) ) ;//green is RAY STARTED INSIDE
return true ;
}
Vector tmins, tmaxes ;
// These are red in the profiler.
tmins = (min - ray.startPos) / ray.direction ;
tmaxes = (max - ray.startPos) / ray.direction ;
Vector* sols[2] = { &tmins, &tmaxes } ;
int solS=0, solI=0 ;
real smallestT = HUGE ; // smallest valid t ("so far"). put at inf so first time everything smaller than it.
Vector closestRaypoint ; // smallest rayPoint (associated with "smallest t so far")
for( int s = 0 ; s < 2 ; s++ )
{
Vector& candSols = *sols[s] ;
// i walks xyz
for( int i = 0 ; i < 3 ; i++ )
{
real& t = candSols.e[i] ; // candidate t
// validity: 0 <= t <= length
if( BetweenIn( t, 0, ray.length ) )
{
Vector raypoint = ray.at( t ) ;
// AND ON FACE
// o1 and o2 are the indices of the OTHER faces,
// if i==0, o1=1, o2=2
int o1 = ( i + 1 ) % 3 ; // if( i==0 ) o1=1, o2=2;
int o2 = ( i + 2 ) % 3 ; // else if( i == 1) o1=2, o2=0;
if( InRect( raypoint.e[ o1 ],raypoint.e[ o2 ],
min.e[o1], min.e[o2],
max.e[o1], max.e[o2] ) )
{
// this one wins, if it's smallest so far
if( t < smallestT )
{
smallestT = t ;
closestRaypoint = raypoint ;
// record what face it was
solS = s ;
solI = i ;
}
}
}
}
}
// now here, it's possible smallestT was unassigned,
// which means it'll still be HUGE
if( smallestT == HUGE )
{
// no solution
///generateDebugLines( Vector(.2,.2,.2) ) ;//total miss
return false ;
}
else
{
// there was an intersection.
///generateDebugLines( Vector(1,0,0) ) ;//red means it was a hit
pt = closestRaypoint ;
return true ;
}
}
bool AABB::intersects( const Ray& ray )
{
// VERY IMPORTANT CHECK: If the ray starts inside
// the box, then it's a hit. This was important for octrees.
if( containsIn( ray.startPos ) || containsIn( ray.getEndPoint() ) )
return true ;
#define TECH 0
#if TECH==0
// the algorithm says, find 3 t's,
Vector t ;
// LARGEST t is the only only we need to test if it's on the face.
for( int i = 0 ; i < 3 ; i++ )
{
if( ray.direction.e[i] > 0 ) // CULL BACK FACE
t.e[i] = ( min.e[i] - ray.startPos.e[i] ) / ray.direction.e[i] ;
else
t.e[i] = ( max.e[i] - ray.startPos.e[i] ) / ray.direction.e[i] ;
}
int mi = t.maxIndex() ;
if( BetweenIn( t.e[mi], 0, ray.length ) )
{
Vector pt = ray.at( t.e[mi] ) ;
// check it's in the box in other 2 dimensions
int o1 = ( mi + 1 ) % 3 ; // i=0: o1=1, o2=2, i=1: o1=2,o2=0 etc.
int o2 = ( mi + 2 ) % 3 ;
return BetweenIn( pt.e[o1], min.e[o1], max.e[o1] ) &&
BetweenIn( pt.e[o2], min.e[o2], max.e[o2] ) ;
}
return false ;
#elif TECH==1
// This culls the back faces first, and gives you the answer with the largest valid t
for( int i = 0 ; i < 3 ; i++ )
{
int o1 = ( i + 1 ) % 3 ; // i=0: o1=1, o2=2, i=1: o1=2,o2=0 etc.
int o2 = ( i + 2 ) % 3 ;
// min.x (NX) is possible, PX won't be hit. (unless you're inside the box.)
if( ray.direction.e[i] > 0 ) // CULL BACK FACE
{
real t = ( min.e[i] - ray.startPos.e[i] ) / ray.direction.e[i] ;
// 1. CHECK VALID T
if( BetweenIn( t, 0, ray.length ) )
{
// 2. CHECK IN BOX
Vector pt = ray.at( t ) ;
if( BetweenIn( pt.e[o1], min.e[o1], max.e[o1] ) && BetweenIn( pt.e[o2], min.e[o2], max.e[o2] ) )
return true ; // it's valid in the box
}
}
else if( ray.direction.e[i] < 0 ) // max.x (PX) is possible
{
real t = ( max.e[i] - ray.startPos.e[i] ) / ray.direction.e[i] ;
if( BetweenIn( t, 0, ray.length ) ) // valid t
{
Vector pt = ray.at( t ) ;
if( BetweenIn( pt.e[o1], min.e[o1], max.e[o1] ) && BetweenIn( pt.e[o2], min.e[o2], max.e[o2] ) )
return true ; // it's valid in the box
}
}
}
return false ; // no hit.
#elif TECH==2
// This solves ALL 6 solutions and finds the shortest t.
// Rays starting and ending in an octree node must be considered
// to hit the node.
// if the start point OR the end point is in the AABB, then it's a hit.
// These are red in the profiler.
Vector tmins = (min - ray.startPos) / ray.direction ;
Vector tmaxes = (max - ray.startPos) / ray.direction ;
Vector* sols[2] = { &tmins, &tmaxes } ;
for( int s = 0 ; s < 2 ; s++ )
{
Vector& candSols = *sols[s] ;
// i walks xyz
for( int i = 0 ; i < 3 ; i++ )
{
real& t = candSols.e[i] ; // candidate t
// validity: 0 <= t <= length
if( BetweenIn( t, 0, ray.length ) )
{
Vector raypoint = ray.at( t ) ;
// AND ON FACE
// o1 and o2 are the indices of the OTHER faces,
// if i==0, o1=1, o2=2
int o1 = ( i + 1 ) % 3 ; // if( i==0 ) o1=1, o2=2;
int o2 = ( i + 2 ) % 3 ; // else if( i == 1) o1=2, o2=0;
if( InRect( raypoint.e[ o1 ],raypoint.e[ o2 ],
min.e[o1], min.e[o2],
max.e[o1], max.e[o2] ) )
{
// the box got hit, any side
return true ;
}
}
}
}
// No hit
return false ;
#endif
}
// Moeller-Trumbore
bool Triangle::hit(const Ray& ray, const Ray_Tracer* rt,
float t_min, float t_max, Ray_Hit& rh, bool shadow) const {
// Absolute Triangle Vertex Positions
V3& v0 = m->verts[inds[0]];
V3& v1 = m->verts[inds[1]];
V3& v2 = m->verts[inds[2]];
// Two edges of triangle
V3 e0, e1;
e0 = v1 - v0;
e1 = v2 - v0;
V3 p = ray.s.cross(e1);
float deter = e0.dot(p);
if (deter > -EPSILON && deter < EPSILON)
return false;
V3 t = ray.o - v0;
// Store the inverse to reduce divisions
float inv_deter = 1.0 / deter;
float u = t.dot(p) * inv_deter;
if (u < 0.0 || u > 1.0)
return false;
V3 q = t.cross(e0);
float v = ray.s.dot(q) * inv_deter;
if (v < 0.0 || u + v > 1.0)
return false;
float t_inter = e1.dot(q) * inv_deter;
if (t_inter < t_min || t_inter > t_max) {
//std::cout << "Cull: " << t_inter << '\t' <<t_min<< '\t' <<t_max<< std::endl;
return false;
}
rh.t = t_inter;
rh.col = 0.2*m->mat.col;
rh.shape = m;
if (shadow || ray.depth >= rt->depth_limit)
return true;
/*
if (is_light) {
rh.col = Color(1.0, 1.0, 1.0);
return true;
}
*/
V3 int_loc = ray.at(t_inter);
// Shadow
for (Shape* light : rt->lights) {
// BIG ASSUMPTION THAT ALL LIGHTS ARE SPHERES
Sphere* sph = static_cast<Sphere*>(light);
// Make ray from intersection to light
V3 int_to_light = sph->c - int_loc;
float dist_to_light = int_to_light.norm();
int_to_light.normalize();
Ray shadow_ray(int_loc + EPSILON*int_to_light, int_to_light, ray.depth + 1);
Ray_Hit shadow_hit;
if (rt->kd->hit_helper(true, rt->kd->root, shadow_ray, rt,
EPSILON, dist_to_light, shadow_hit, true, 0)) {
if (!shadow_hit.shape->is_light) {
continue;
}
}
float inner = int_to_light.dot(normal);
if (inner > 0.0) {
rh.col += sph->mat.col *inner* m->mat.diff * m->mat.col;
}
}
// Reflection
V3 refl_dir = ray.s - 2.0f * (normal.dot(ray.s)) * normal;
Ray refl_ray(int_loc + EPSILON*refl_dir, refl_dir, ray.depth + 1);
Ray_Hit refl_hit;
if (rt->kd->hit_helper(true, rt->kd->root, refl_ray, rt,
EPSILON, FLT_MAX, refl_hit, false, 0)) {
//if (rt->trace(refl_ray, EPSILON, FLT_MAX, refl_hit, false)) {
rh.col += m->mat.refl*refl_hit.col * refl_hit.shape->mat.col;
}
return true;
}
bool AABB::intersect(const Ray& ray, float& t, glm::vec3& normal, uint64_t moxelIndex)
{
float normalDirection[3] = {1.0f,1.0f,1.0f};
normal = glm::vec3(0.0f,0.0f,0.0f);
//cout << "AABB: ";
//print();
//cout << "Ray: ";
//ray.print();
// If the ray starts inside the box, or ends inside
if (contains(ray.position))
{
return false;
}
// the algorithm says, find 3 t's,
glm::vec3 tVals;
// LARGEST t is the only one we need to test if it's on the face.
for (int i = 0 ; i < 3 ; i++)
{
if (ray.direction[i] == 0)
{
tVals[i] = -FLT_MAX;
}
else if(ray.direction[i] > 0) // CULL BACK FACE
{
tVals[i] = ( mins[i] - ray.position[i] ) / ray.direction[i];
// If the ray direction is positive, it will hit the more negative AABB side which makes
// the normal point in the negative direction
normalDirection[i] = -1.0f;
}
else
{
tVals[i] = ( maxs[i] - ray.position[i] ) / ray.direction[i];
// If the ray direction is positive, it will hit the more positive AABB side which makes
// the normal point in the positive direction
normalDirection[i] = 1.0f;
}
}
// cout << "tVals: ";
// for (int i = 0; i < 3; ++i)
// {
// cout << "(" << i << ": " << tVals[i] << ") ";
// }
// cout << endl;
// Get the max index
float maxValue = tVals[0];
int maxIndex = 0;
if (tVals[1] > maxValue)
{
maxValue = tVals[1];
maxIndex = 1;
}
if (tVals[2] > maxValue)
{
maxValue = tVals[2];
maxIndex = 2;
}
t = maxValue;
normal[maxIndex] = normalDirection[maxIndex];
if (tVals[maxIndex] > 0.0f)
{
glm::vec3 pt = ray.at(tVals[maxIndex]);
// check it's in the box in other 2 dimensions
int o1 = ( maxIndex + 1 ) % 3; // i=0: o1=1, o2=2, i=1: o1=2,o2=0 etc.
int o2 = ( maxIndex + 2 ) % 3;
return inRange(pt[o1], mins[o1], maxs[o1]) && inRange(pt[o2], mins[o2], maxs[o2]) ;
}
return false ; // the ray did not hit the box.
}
void Scene::jiggle(Ray& ray){
Point pjig = ray.at(pow(2,-32));
ray = Ray(pjig,ray.D);
}
pair<int, float> Grid::trace(const Ray &ray, float tmin, float tmax, int ignored_id, int flags) const {
float3 p1 = ray.at(tmin), p2 = ray.at(tmax);
int2 pos = worldToGrid((int2)p1.xz()), end = worldToGrid((int2)p2.xz());
//TODO: verify for rays going out of grid space
if(!isInsideGrid(pos) || !isInsideGrid(end))
return make_pair(-1, constant::inf);
// Algorithm idea from: RTCD by Christer Ericson
int dx = end.x > pos.x? 1 : end.x < pos.x? -1 : 0;
int dz = end.y > pos.y? 1 : end.y < pos.y? -1 : 0;
float cell_size = (float)node_size;
float inv_cell_size = 1.0f / cell_size;
float lenx = fabs(p2.x - p1.x);
float lenz = fabs(p2.z - p1.z);
float minx = float(node_size) * floorf(p1.x * inv_cell_size), maxx = minx + cell_size;
float minz = float(node_size) * floorf(p1.z * inv_cell_size), maxz = minz + cell_size;
float tx = (p1.x > p2.x? p1.x - minx : maxx - p1.x) / lenx;
float tz = (p1.z > p2.z? p1.z - minz : maxz - p1.z) / lenz;
float deltax = cell_size / lenx;
float deltaz = cell_size / lenz;
int out = -1;
float out_dist = tmax + constant::epsilon;
while(true) {
int node_id = nodeAt(pos);
const Node &node = m_nodes[node_id];
if(flagTest(node.obj_flags, flags) && intersection(ray, node.bbox) < out_dist) {
const Object *objects[node.size];
int count = extractObjects(node_id, objects, ignored_id, flags);
for(int n = 0; n < count; n++) {
float dist = intersection(ray, objects[n]->bbox);
if(dist < out_dist) {
out_dist = dist;
out = objects[n] - &m_objects[0];
}
}
if(node.is_dirty)
updateNode(node_id);
}
if(tx <= tz || dz == 0) {
if(pos.x == end.x)
break;
tx += deltax;
pos.x += dx;
}
else {
if(pos.y == end.y)
break;
tz += deltaz;
pos.y += dz;
}
float ray_pos = tmin + max((tx - deltax) * lenx, (tz - deltaz) * lenz);
if(ray_pos >= out_dist)
break;
}
return make_pair(out, out_dist);
}
Color Scene::trace(const Ray &ray, int steps,double eta1)
{
// Find hit object and distance
Hit min_hit(std::numeric_limits<double>::infinity(),Vector());
Object *obj = NULL;
for (unsigned int i = 0; i < objects.size(); ++i) {
Hit hit(objects[i]->intersect(ray));
if (hit.t<min_hit.t) {
min_hit = hit;
obj = objects[i];
}
}
// No hit? Return background color.
if (!obj) return Color(0.0, 0.0, 0.0);
Material *material = obj->material; //the hit objects material
Point hit = ray.at(min_hit.t); //the hit point
Vector N = min_hit.N; //the normal at hit point
Vector V = -ray.D; //the view vector
/****************************************************
* This is where you should insert the color
* calculation (Phong model).
*
* Given: material, hit, N, V, lights[]
* Sought: color
*
* Hints: (see triple.h)
* Triple.dot(Vector) dot product
* Vector+Vector vector sum
* Vector-Vector vector difference
* Point-Point yields vector
* Vector.normalize() normalizes vector, returns length
* double*Color scales each color component (r,g,b)
* Color*Color dito
* pow(a,b) a to the power of b
****************************************************/
// extract and/or declare variables
// for lighting calculations
Color ambient = Color(1.0,1.0,1.0); // ambient colour
Color base = material->color; // material colour
double ka = material->ka; // ambient intensity;
double kd = material->kd; // diffuse intensity
double ks = material->ks; // specular intensity
double e = material->n; // exponent of specular highlight size
double reflect = material->reflect; // reflect coefficient
double refract = material->refract; // refraction coefficient
double eta2 = material->eta; // refraction index
if(eta1 == eta2){
eta2 = AIR_ETA;
}
// get reflected ray
Vector vec_ref = ray.D - (2.0 *(ray.D.dot(N))*N); // reflect ray direction
Ray ray_ref(hit,vec_ref); //reflect ray
// jiggle the ray
jiggle(ray_ref);
// hack
Vector frac_n;
if(ray.D.dot(N) < 0.0){
frac_n = N;
}else{
frac_n = -N;
}
// get refracted ray
bool frac_flag;
Vector frac_dir = fractf(eta1,eta2,ray.D,frac_n); // direction of refraction
Ray ray_frac(hit,frac_dir); // ray going out of the material
if(frac_dir.length_2() > 0.0 && refract > 0.0){
frac_flag = true;
}else{
frac_flag = false;
}
// jiggle the ray
jiggle(ray_frac);
Color c_ref; // colour of reflected ray
Color c_frac; // colour of refracted ray
// recursively trace reflected/refracted rays up to steps times
if(steps > 0){
if(reflect > 0.0) c_ref = trace(ray_ref,steps-1,eta1);
if(frac_flag) c_frac = trace(ray_frac, steps-1,eta2);
}
Color color = ka * base * ambient; // set ambient colour
for(unsigned int i = 0;i<lights.size();i++){
bool shaded = false; // flag if the current light cast a shadow
Vector L = hit - lights[i]->position; // vector of light direction
Vector SL = lights[i]->position - hit; // vector of shadow feeler
L.normalize();
SL.normalize();
// get shadow feelers
Ray feeler = Ray(hit,SL);
//jiggle Ray
jiggle(feeler);
// test to see if object is in shadow
if(shadows){
for(unsigned int j = 0;j<objects.size();j++){
Hit test(objects[j]->intersect(feeler));
if(test.t >= 0.0) {
shaded = true;
break;
}
}
}
if(!shaded){
Color lc = lights[i]->color; // colour of light
double lnDot = L.dot(N); // dot product of light
Vector R = L - (2.0*N*lnDot); // reflection vector
R.normalize();
double rvDot = R.dot(V) ;
color += (kd*base*lc*max(0.0,lnDot)) + (ks*lc*pow(max(0.0,rvDot),e));
}
}
color += reflect*c_ref + refract*c_frac;
return color;
}
/**
* @brief intersect a geometric object.
* @param ray_ the ray
* @param p_diff_geom_ the result of the intersection
* @return true if the ray intersects the geometry. Modifies the ray_.max_t() value, intersect only if the intersection
* is before ray_.max_t()
* @todo Factorize code shared by Box3D::clip()
*
* Adapted from http://www.geometrictools.com/LibMathematics/Intersection/Wm5IntrLine3Box3.cpp
*/
bool intersect (Ray& ray_, Diff_Geom * p_diff_geom_) const {
float t0 = -ray_.ray_epsilon();
float t1 = ray_.max_t();
// Convert linear component to box coordinates.
Vector3D diff = ray_.ori() - m_center;
Vector3D BOrigin(
diff.dot(m_axis[0]),
diff.dot(m_axis[1]),
diff.dot(m_axis[2])
);
Vector3D BDirection(
ray_.dir().dot(m_axis[0]),
ray_.dir().dot(m_axis[1]),
ray_.dir().dot(m_axis[2])
);
float saveT0 = t0, saveT1 = t1;
bool notAllClipped;
unsigned char updated;
int nt0, nt1;
notAllClipped = clip(+BDirection.x(), -BOrigin.x()-m_extent[0], t0, t1, updated);
if (updated == 1)
nt0 = 0;
else if (updated == 2)
nt1 = 0;
notAllClipped = notAllClipped && clip(-BDirection.x(), +BOrigin.x()-m_extent[0], t0, t1, updated);
if (updated == 1)
nt0 = 1;
else if (updated == 2)
nt1 = 1;
notAllClipped = notAllClipped && clip(+BDirection.y(), -BOrigin.y()-m_extent[1], t0, t1, updated);
if (updated == 1)
nt0 = 2;
else if (updated == 2)
nt1 = 2;
notAllClipped = notAllClipped && clip(-BDirection.y(), +BOrigin.y()-m_extent[1], t0, t1, updated);
if (updated == 1)
nt0 = 3;
else if (updated == 2)
nt1 = 3;
notAllClipped = notAllClipped && clip(+BDirection.z(), -BOrigin.z()-m_extent[2], t0, t1, updated);
if (updated == 1)
nt0 = 4;
else if (updated == 2)
nt1 = 4;
notAllClipped = notAllClipped && clip(-BDirection.z(), +BOrigin.z()-m_extent[2], t0, t1, updated);
if (updated == 1)
nt0 = 5;
else if (updated == 2)
nt1 = 5;
if (notAllClipped && (t0 != saveT0 || t1 != saveT1)) {
if ( (t0 > ray_.ray_epsilon() ) && (t0 < ray_.max_t()) ){
Vector3D normal = m_axis[nt0/2];
if (nt0%2)
normal = -normal;
p_diff_geom_->set_pos(ray_.at(t0));
p_diff_geom_->set_normal(normal);
p_diff_geom_->set_t(t0);
ray_.set_max_t(t0);
return true;
} else if ( (t1 > ray_.ray_epsilon()) && (t1 < ray_.max_t()) ){
Vector3D normal = m_axis[nt1/2];
if (nt1%2)
normal = -normal;
p_diff_geom_->set_pos(ray_.at(t1));
p_diff_geom_->set_normal(normal);
p_diff_geom_->set_t(t1);
ray_.set_max_t(t1);
return true;
} else
return false;
} else {
return false;
}
}
int get_clip_points(Ray& ray_, Diff_Geom ipoints[2], float t[2]) const{
int numintersection = 0;
Vector3D E = ray_.ori() - m_vertex;
float AdD = m_axis.dot(ray_.dir());
float cosSqr = m_costheta*m_costheta;
float AdE = m_axis.dot(E);
float DdE = ray_.dir().dot(E);
float EdE = E.dot(E);
float c2 = AdD*AdD-cosSqr;
float c1 = AdD*AdE - cosSqr*DdE;
float c0 = AdE*AdE - cosSqr*EdE;
float dot;
Vector3D zero;
if (std::fabs(c2)>0) {
float discr = c1*c1 - c0*c2;
float invC2 = 1.f/c2;
if (discr < 0) {
// No intersection
return 0;
} else if (discr > 0) {
// two distinct intersections
float root = std::sqrt(discr);
// entry point
t[numintersection] = (-c1 + root) * invC2;
E = ray_.at(t[numintersection]) - m_vertex;
dot = E.dot(m_axis);
if ( (dot > 0) && (dot <= m_height))
{
fillConicalDiffGeom(ipoints[numintersection], ray_, t[numintersection], true);
++numintersection;
}
// exit point
t[numintersection] = (-c1 - root) * invC2;
E = ray_.at(t[numintersection]) - m_vertex;
dot = E.dot(m_axis);
if ( (dot > 0) && (dot <= m_height))
{
fillConicalDiffGeom(ipoints[numintersection], ray_, t[numintersection], false);
++numintersection;
}
return numintersection;
} else {
// one reapeated intersection : ray is tangent to the cone
// may be return 0 instead of an intersection ?
return 0;
t[numintersection] = -c1 * invC2;
E = ray_.at(t[numintersection]) - m_vertex;
dot = E.dot(m_axis);
if ( (dot > 0) && (dot <= m_height)) {
fillConicalDiffGeom(ipoints[numintersection], ray_, t[numintersection], true);
++numintersection;
}
return numintersection;
}
} else if (std::fabs(c1) > 0) {
// the ray is on the boundary of the cone
// we consider no intersection
// TODO : check this for CSG
return 0;
} else {
//return false;
// Cone contains ray V+tD
// The ray intersect the cone exactly at its vertex :(
// TODO : manage this particular case in another function
ipoints[numintersection].set_pos(m_vertex);
ipoints[numintersection].set_normal(-m_axis);
ipoints[numintersection].set_u(1.f);
ipoints[numintersection].set_v(0.f);
E = ray_.ori() - m_vertex;
t[numintersection] = ( (E.dot(ray_.dir())<0) ? std::sqrt(EdE) : -std::sqrt(EdE) ) ;
ipoints[numintersection].set_t(t[numintersection]);
ipoints[numintersection].set_in(true);
ipoints[numintersection].set_u(0.f);
ipoints[numintersection].set_v(1.f);
// todo : compute here normal derivatives (according to x and y directions on the image plane)
ipoints[numintersection].set_dNdx(zero);
ipoints[numintersection].set_dNdy(zero);
++numintersection;
// check with cap plane
Plane cap(m_vertex + m_axis * m_height, m_axis);
IntervalSet capset;
if (cap.clip(ray_, capset)) {
if (capset.bounds()[0].t < t[numintersection-1]) {
t[numintersection] = t[numintersection-1];
ipoints[numintersection] = ipoints[numintersection-1];
--numintersection;
} else {
capset.bounds()[0].data->set_in(false);
}
ipoints[numintersection] = *(capset.bounds()[0].data);
// TODO : update u, v dTdx and dTdy
ipoints[numintersection].set_u(ipoints[numintersection].u()/(PSCALE*m_radius));
ipoints[numintersection].set_v(ipoints[numintersection].v()/(PSCALE*m_radius));
ipoints[numintersection].set_dTdx(ipoints[numintersection].dTdx()* (1.f/(PSCALE*m_radius)));
ipoints[numintersection].set_dTdy(ipoints[numintersection].dTdy()* (1.f/(PSCALE*m_radius)));
delete capset.bounds()[0].data;
delete capset.bounds()[1].data;
return 2;
} else {
// must never reach this point !
assert(false);
return 0;
}
}
}
Hit Box::intersect(const Ray &ray)
{
/****************************************************
* RT1.1: INTERSECTION CALCULATION
* t is the distance between the ray origin and the closest face of the box
****************************************************/
/* Mathematic Method
* We consider a cube like the intersection of 3 slabs
* We first start to calculate the distance between the ray and the 2D slab on x,y of the cube
* Then repeat it for z
*/
double t, tentry, texit, tyentry, tyexit, tzentry, tzexit;
/* A box is defined with two point: the minimum and maximum exent points (min and max) */
/* extents[0] = min extent of the box & extents[1] = max extent of the box*/
Point extents[2] = {min,max};
/* First we start in 2D
* Exemple for tentry initialized with txentry:
* ray.O.x + txentry*ray.D.x = min.x (= extents[0].x) if ray.D.x >= 0
* <=> tentryx = (min.x - ray.O.x)/ ray.D.x
* or
* ray.O.x + txentry*ray.D.x = max.x (= extents[1].x) if ray.D.x < 0
* <=> tentryx = (max.x - ray.O.x)/ ray.D.x
*/
tentry = (extents[(ray.D.x < 0.0 && ray.D.x != -0.0)].x - ray.O.x) / ray.D.x;
texit = (extents[1-(ray.D.x < 0.0 && ray.D.x != -0.0)].x - ray.O.x) / ray.D.x;
tyentry = (extents[(ray.D.y < 0.0 && ray.D.y != -0.0)].y - ray.O.y) / ray.D.y;
tyexit = (extents[1-(ray.D.y < 0.0 && ray.D.y != -0.0)].y - ray.O.y) / ray.D.y;
/* Case where there is no Hit*/
if ((tentry > tyexit) || (tyentry > texit)){
return Hit::NO_HIT();
}
/* Case where the entry point is on y */
if (tyentry > tentry) {
tentry = tyentry;
}
/* Case where the exit point is on y */
if (tyexit < texit) {
texit = tyexit;
}
/* The we compare tentry and texit with the 3rd dimension */
tzentry = (extents[(ray.D.z < 0.0 && ray.D.z != -0.0)].z - ray.O.z) / ray.D.z;
tzexit = (extents[1-(ray.D.z < 0.0 && ray.D.z != -0.0)].z - ray.O.z) / ray.D.z;
/* Case where there is no Hit*/
if ((tentry > tzexit) || (tzentry > texit))
return Hit::NO_HIT();
/* Case where the entry point is on z */
if (tzentry > tentry) {
tentry = tzentry;
}
/* Case where the exit point is on z */
if (tzexit < texit) {
texit = tzexit;
}
/* Choose t according to the tentry and texit cases*/
if (tentry <= 0){
t = texit;
}
else{
t = tentry;
}
/****************************************************
* RT1.2: NORMAL CALCULATION
****************************************************/
Vector N;
Point a,b;
Vector v;
Point center = Point((min.x + max.x)/2.0,(min.y + max.y)/2.0,(min.z + max.z)/2.0);
Point hit = ray.at(t);
double side_x = fabs(max.x - min.x)/2.0;
double side_y = fabs(max.y - min.y)/2.0;
double side_z = fabs(max.z - min.z)/2.0;
if (hit.y <= center.y - side_y + 0.1 && hit.y >= center.y - side_y - 0.1) {
// Face 6
a = Point(center.x,center.y - side_y,center.z);
//cout << "6";
}
else if ( hit.y <= center.y + side_y + 0.1 && hit.y >= center.y + side_y - 0.1) {
// Face 3
a = Point(center.x,center.y + side_y,center.z);
//cout << "3";
}
else if (hit.x <= center.x - side_x + 0.1 && hit.x >= center.x - side_x - 0.1) {
// Face 5
a = Point(center.x- side_x,center.y,center.z);
//cout << "5";
}
else if ( hit.x <= center.x + side_x + 0.1 && hit.x >= center.x + side_x - 0.1) {
// Face 2
a = Point(center.x+ side_x,center.y ,center.z);
//cout << "2";
}
else if (hit.z <= center.z - side_z + 0.1 && hit.z >= center.z - side_z - 0.1) {
// Face 4
a = Point(center.x,center.y,center.z- side_z);
//cout << "4";
}
else if (hit.z <= center.z + side_z + 0.1 && hit.z >= center.z + side_z - 0.1) {
// Face 1
a = Point(center.x,center.y,center.z+ side_z);
//cout << "1";
}
else {
int x = center.x + side_x;
cout << "?- " << hit.x << " c: " << (int)(x) <<"-";
cout << ((int) (hit.x) >= (int)(x)) <<"-";
}
v = hit - a;
b = center + v;
N = (hit - b).normalized();
/* Choose of the good direction
if (N.dot(ray.D) > 0){
N = -N;
}*/
//cout << "x :" << hit.x <<" y :" << hit.y <<" z :" << hit.z << "\n" ;
return Hit(t,N);
}
// ----------------------------------------------------- tracePhong ------------------------------------------------------------------ //
Color Scene::tracePhongGooch(const Ray &ray, int recursionDepth){
// Find hit object and distance
Hit min_hit(std::numeric_limits<double>::infinity(),Vector());
Object *obj = NULL;
for (unsigned int i = 0; i < objects.size(); ++i) {
Hit hit(objects[i]->intersect(ray));
if (hit.t<min_hit.t) {
min_hit = hit;
obj = objects[i];
}
}
// No hit? Return background color.
if (!obj) return Color(0.0, 0.0, 0.0);
Material *material = obj->material; //the hit objects material
Point hit = ray.at(min_hit.t); //the hit point
Vector N = min_hit.N; //the normal at hit point
Vector V = -ray.D; //the view vector
/****************************************************
* This is where you should insert the color
* calculation (Phong model).
*
* Given: material, hit, N, V, lights[]
* Sought: color
*
* Hints: (see triple.h)
* Triple.dot(Vector) dot product
* Vector+Vector vector sum
* Vector-Vector vector difference
* Point-Point yields vector
* Vector.normalize() normalizes vector, returns length
* double*Color scales each color component (r,g,b)
* Color*Color dito
* pow(a,b) a to the power of b
****************************************************/
Color color;
//For each light
for(unsigned int i = 0; i < lights.size(); i++){
bool isShadow = false;
if (rendermode == phong) //Ambiant
color += lights[i]->color * material->color * material->ka;
//Shadow
if(Shadow){
//Ray from light to object
Ray light(lights[i]->position, hit - lights[i]->position);
//Hit from light to nearest object
Hit minHit = findMinHit(light);
//Hit from current object to light
Hit currentHit(obj->intersect(light));
//
if (minHit.t < currentHit.t) isShadow = true;
}
//No Shadow -> Calculate colors
if(!isShadow){
//The light vector
Vector L = lights[i]->position - hit;L.normalize();
//The R vector (required for specular shading)
Vector R = (-1*L) + 2 * (L.dot(N)) * N;
if (rendermode == phong) //Diffuse
if (material->texture){
color += (max(0.0,N.dot(L)) * lights[i]->color) * obj->calcTexture(hit) * material->kd;
} else {
color += (max(0.0,N.dot(L)) * lights[i]->color) * material->color * material->kd;
}
if (rendermode == gooch && ray.D.dot(N)<-0.2){
Color kCool = Color(0.0,0.0,kBlue) + alpha * (lights[i]->color * material->color * material->kd);
Color kWarm = Color(kYellow,kYellow,0.0) + beta * (lights[i]->color * material->color * material->kd);
color += (kCool *(1 - N.dot(L))/2) + (kWarm * (1 + N.dot(L))/2);
}
//Specular + dot(R,V)^n LightColor ks
color += pow(max(0.0,R.dot(V)), material->n) * lights[i]->color * material->ks;
}
}
//Reflection
if(recursionDepth <= maxRecursionDepth && ray.D.dot(N)<-0.2){
Color buffer(0.0, 0.0, 0.0);
//The reflected direction
Vector reflectV((V + 2*(-N.dot(V))*N));
for (unsigned int i=0; i<4; i++){
//The reflected ray
Ray reflect(hit + 0.001 * N, -reflectV);
//Calculate reflection through recursion
buffer += material->ks*tracePhongGooch(reflect, recursionDepth+1);
reflectV.x += 0.01 * cos(0.5);
reflectV.y += 0.01 * sin(0.5);
}
//Color = average buffer value
color += buffer/4;
}
return color;
}
/**
* @brief get_clip_points
* @param ray_
* @param ipoints
* @param t
* @return the number of clipping position on the ray (0 to 2)
*/
int get_clip_points(Ray& ray_, Diff_Geom ipoints[2], float t[2]) const{
int numintersection = 0;
Vector3D E = ray_.ori() - m_vertex;
float AdD = m_axis.dot(ray_.dir());
float cosSqr = m_costheta*m_costheta;
float AdE = m_axis.dot(E);
float DdE = ray_.dir().dot(E);
float EdE = E.dot(E);
float c2 = AdD*AdD-cosSqr;
float c1 = AdD*AdE - cosSqr*DdE;
float c0 = AdE*AdE - cosSqr*EdE;
float dot;
if (std::fabs(c2)>0) {
float discr = c1*c1 - c0*c2;
float invC2 = 1.f/c2;
if (discr < 0) {
// No intersection
return 0;
} else if (discr > 0) {
// two distinct intersections
float root = std::sqrt(discr);
// entry point
t[numintersection] = (-c1 + root) * invC2;
ipoints[numintersection].set_pos(ray_.at(t[numintersection]));
E = ipoints[numintersection].pos() - m_vertex;
dot = E.dot(m_axis);
if ( (dot > 0) && (dot <= m_height))
{
Vector3D normal=compute_normal(ipoints[numintersection].pos());
ipoints[numintersection].set_normal(normal);
ipoints[numintersection].set_t(t[numintersection]);
++numintersection;
}
// exit point
t[numintersection] = (-c1 - root) * invC2;
ipoints[numintersection].set_pos(ray_.at(t[numintersection]));
E = ipoints[numintersection].pos() - m_vertex;
dot = E.dot(m_axis);
if ( (dot > 0) && (dot <= m_height))
{
Vector3D normal=compute_normal(ipoints[numintersection].pos());
ipoints[numintersection].set_normal(normal);
ipoints[numintersection].set_t(t[numintersection]);
++numintersection;
}
return numintersection;
} else {
// one reapeated intersection : ray is tangent to the cone
// may be return 0 instead of an intersection ?
return 0;
t[numintersection] = -c1 * invC2;
ipoints[numintersection].set_pos(ray_.at(t[numintersection]));
E = ipoints[numintersection].pos() - m_vertex;
dot = E.dot(m_axis);
if ( (dot > 0) && (dot <= m_height)) {
Vector3D normal=compute_normal(ipoints[numintersection].pos());
ipoints[numintersection].set_normal(normal);
ipoints[numintersection].set_t(t[numintersection]);
++numintersection;
}
return numintersection;
}
} else if (std::fabs(c1) > 0) {
// the ray is on the boundary of the cone
// we consider no intersection
// TODO : check this for CSG
return 0;
} else {
//return false;
// Cone contains ray V+tD
// The ray intersect the cone exactly at its vertex :(
ipoints[numintersection].set_pos(m_vertex);
ipoints[numintersection].set_normal(-m_axis);
E = ray_.ori() - m_vertex;
t[numintersection] = ( (E.dot(ray_.dir())<0) ? std::sqrt(EdE) : -std::sqrt(EdE) ) ;
ipoints[numintersection].set_t(t[numintersection]);
++numintersection;
// TODO compute cap plane intersection
// check with cap plane
Plane cap(m_vertex + m_axis * m_height, m_axis);
IntervalSet capset;
if (cap.clip(ray_, capset)) {
if (capset.bounds()[0].t < t[numintersection-1]) {
t[numintersection] = t[numintersection-1];
ipoints[numintersection] = ipoints[numintersection-1];
--numintersection;
}
ipoints[numintersection] = *(capset.bounds()[0].data);
delete capset.bounds()[0].data;
delete capset.bounds()[1].data;
return 2;
} else {
// must never reach this point !
assert(false);
return 0;
}
}
}
/**
* @brief clip a ray by a Box3D.
* @param ray_ the ray to clip
* @param bounds ray sorted bounds of the resulting clipping segment.
* @return true if ray was clipped. bounds parameter is filld by this method
*
* For simple convex objects, there is two values in bounds that represent in and out events.
* An in event is whe the ray enters the geometry, an out is when the ray leaves the geometry.
*
* @todo Factorize code shared by Box3D::intersect()
*
* Adapted from http://www.geometrictools.com/LibMathematics/Intersection/Wm5IntrLine3Box3.cpp
*
*/
bool clip(Ray& ray_, IntervalSet &bounds) const {
float t0 = std::numeric_limits<float>::min();
float t1 = std::numeric_limits<float>::max();
// Convert linear component to box coordinates.
Vector3D diff = ray_.ori() - m_center;
Vector3D BOrigin(
diff.dot(m_axis[0]),
diff.dot(m_axis[1]),
diff.dot(m_axis[2])
);
Vector3D BDirection(
ray_.dir().dot(m_axis[0]),
ray_.dir().dot(m_axis[1]),
ray_.dir().dot(m_axis[2])
);
float saveT0 = t0, saveT1 = t1;
bool notAllClipped;
unsigned char updated;
int nt0, nt1;
notAllClipped = clip(+BDirection.x(), -BOrigin.x()-m_extent[0], t0, t1, updated);
if (updated == 1)
nt0 = 0;
else if (updated == 2)
nt1 = 0;
notAllClipped = notAllClipped && clip(-BDirection.x(), +BOrigin.x()-m_extent[0], t0, t1, updated);
if (updated == 1)
nt0 = 1;
else if (updated == 2)
nt1 = 1;
notAllClipped = notAllClipped && clip(+BDirection.y(), -BOrigin.y()-m_extent[1], t0, t1, updated);
if (updated == 1)
nt0 = 2;
else if (updated == 2)
nt1 = 2;
notAllClipped = notAllClipped && clip(-BDirection.y(), +BOrigin.y()-m_extent[1], t0, t1, updated);
if (updated == 1)
nt0 = 3;
else if (updated == 2)
nt1 = 3;
notAllClipped = notAllClipped && clip(+BDirection.z(), -BOrigin.z()-m_extent[2], t0, t1, updated);
if (updated == 1)
nt0 = 4;
else if (updated == 2)
nt1 = 4;
notAllClipped = notAllClipped && clip(-BDirection.z(), +BOrigin.z()-m_extent[2], t0, t1, updated);
if (updated == 1)
nt0 = 5;
else if (updated == 2)
nt1 = 5;
if (notAllClipped && (t0 != saveT0 || t1 != saveT1)) {
if (t1 > t0) {
Vector3D normal = m_axis[nt0/2];
if (nt0%2)
normal = -normal;
Diff_Geom *in = new Diff_Geom(ray_.at(t0), normal, t0);
normal = m_axis[nt1/2];
if (nt1%2)
normal = -normal;
Diff_Geom *out = new Diff_Geom(ray_.at(t1), normal, t1);
bounds.add(in, out);
return true;
} else {
return false;
}
} else {
return false;
}
}
// no one needs teh intersection point for the aabb,
// it's just a boolean check
//bool intersects( const Ray& ray, Intersection* intn ) ;
bool AABB::intersectsRay( const Ray& ray, Vector3f& pt ) const
{
bool rayStartInside = containsPoint( ray.start ) ;
// Rays starting and ending in an octree node must be considered
// to hit the node.
// This is the behavior you USUALLY want.
if( rayStartInside && containsPoint( ray.end ) )
{
pt=ray.start;
return true ;
}
// the algorithm says, find 3 t's,
Vector3f t ;
if( rayStartInside )
{
for( int i = 0 ; i < 3 ; i++ )
{
if( ray.dir.elts[i] > 0 ) // RAY GOING + and we are inside the box.. CULL BACK FACE (mins)
{
t.elts[i] = ( max.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
}
else // RAY GOING - and we are inside the box.. so cull the MAXES
{
t.elts[i] = ( min.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
}
}
}
else
{
// LARGEST t is the only only we need to test if it's on the face.
for( int i = 0 ; i < 3 ; i++ )
{
if( ray.dir.elts[i] > 0 ) // RAY GOING +.. CULL BACK FACE (maxes)
{
// ^ |
// / |
// * |
// -----+-------
// |
// A ray with ray.dir.x>0 means IT WOULD HIT MINFACES FIRST.
// __BUT__, if the ray STARTS AFTER THE MINFACE (ray.start.x > min.x)
// THEN THE RAY STARTED INSIDE THE BOX. to still detect the intersection
// you would use the MAX FACE in that case
t.elts[i] = ( min.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
}
else // RAY GOING -.. so cull the MINS
{
// IF RAY LEFT OF MAXFACE, USE MINFACE
t.elts[i] = ( max.elts[i] - ray.start.elts[i] ) / ray.dir.elts[i] ;
}
// The above code works fine for when you are between min/max in 2 dimensions or less,
// because the detected hits for those dimensions will be BEHIND THE RAY START
// so it's kind of like "using a loophole".. if you are between max/min in 2 dimensions,
// THEN YOU CAN ONLY HIT THE BOX IN THE DIMENSION YOU ARE __NOT__ between max/min in,
// unless you're already inside the box, which is hte cases handled above.
}
}
// The right answer will be
int tIndex ;
if( rayStartInside ) tIndex = t.minIndex() ;
else tIndex = t.maxIndex() ;
if( isBetweenOrdered( t.elts[tIndex], 0, ray.len ) )
{
pt = ray.at( t.elts[tIndex] ) ;
// check it's in the box in other 2 dimensions
int o1 = OTHERAXIS1(tIndex) ; // i=0: o1=1, o2=2, i=1: o1=2,o2=0 etc.
int o2 = OTHERAXIS2(tIndex) ;
return isBetweenOrdered( pt.elts[o1], min.elts[o1], max.elts[o1] ) &&
isBetweenOrdered( pt.elts[o2], min.elts[o2], max.elts[o2] ) ;
}
return false ;
}
