C++ Hit::set方法代码示例

bool Sphere::intersect(const Ray &r, Hit &h, float tmin)
{
	Vec3f v = center - r.getOrigin();
	float tp = v.Dot3(r.getDirection());
	float det = tp*tp - v.Dot3(v) + radius*radius;
	//intersect
	if(det > 0)
	{
		//t'
		det = sqrtf(det); 

		float t1 = tp - det;
		float t2 = tp + det;

		if(t1 > tmin && t1 < h.getT())
		{
			Vec3f normal = (r.pointAtParameter(t1) - center);
			normal /= radius;
			normal.Normalize();
			h.set(t1,material,normal,r);
			return 1;
		}
		else if(t2 > tmin && t2 < h.getT())
		{
			//sphere's normal
			Vec3f normal = (r.pointAtParameter(t2) - center);
			normal /= radius;
			normal.Normalize();
			h.set(t2,material,normal,r);
			return 1;
		}
	}
	return 0;
}

/*
射线与平面求教
即直线的参数方程P = ori + t*dir
代入 平面方程 n * p + D =0

n(R0+t*Rd)+D=0
t=-(D+n*R0)/n*Rd

hit 带走的信息包括：
float t;
Material *material;
Vec3f normal;
Vec3f intersectionPoint;
*/
bool Plane::intersect(const Ray &r, Hit &h, float tmin)
{
	/*
	需要判断射线是否与平面平行
	如果t<0说明平面在视点之后
	以上两个都不产生交点
	*/
	float eps = 1e-6;
	float tmp = normal.Dot3(r.getDirection());
	if (fabs(tmp) < eps)
		return false;
	float t = 0.0f;
	Vec3f r0 = r.getOrigin();
	Vec3f rd = r.getDirection();

	//这里一直不明白
	t = (d - normal.Dot3(r0)) / normal.Dot3(rd);
	if (t < 0)
		return false;
	h.set(t, material, normal, r);
	if (t >= tmin)
		return true;
	else
		return false;
}

bool Triangle::intersect(const Ray &r, Hit &h, float tmin)
{
	Vec3f r0 = r.getOrigin();
	Vec3f rd = r.getDirection();

	Vec3f E1 = a - b;
	Vec3f E2 = a - c;
	Vec3f S = a - r0;

	//参数写错，rd写成r0了……

	float de = det3x3(rd.x(), rd.y(), rd.z(), E1.x(), E1.y(), E1.z(), E2.x(), E2.y(), E2.z());
	if (de == 0.0f)
		return false;
	float t = det3x3(S.x(), S.y(), S.z(), E1.x(), E1.y(), E1.z(), E2.x(), E2.y(), E2.z())/de;
	float belta = det3x3(rd.x(), rd.y(), rd.z(), S.x(), S.y(), S.z(), E2.x(), E2.y(), E2.z()) / de;
	float lamda = det3x3(rd.x(), rd.y(), rd.z(), E1.x(), E1.y(), E1.z(), S.x(), S.y(), S.z()) / de;

	Vec3f normal;
	Vec3f::Cross3(normal, b - a, c - a);
	normal.Normalize();
	h.set(t, material, normal, r);
	if (t >= tmin && belta > 0.0f && lamda > 0.0f && belta + lamda < 1.0f)
		return true;
	else
		return false;
}

bool Grid::intersect(const Ray &r, Hit &h, float tmin)
{
    //Prepare the Material objects
    Vec3f diffuseColor(1, 1, 1);
    Vec3f specularColor(0, 0, 0);
    float exponent = 1;
    Vec3f reflectiveColor(0, 0, 0);
    Vec3f transparentColor(0, 0, 0);
    float indexOfRefraction = 1;
    PhongMaterial *m = new PhongMaterial(diffuseColor, specularColor, exponent,
            reflectiveColor, transparentColor, indexOfRefraction);

    //Start to do DDA
    MarchingInfo mi;
    initializeRayMarch(mi, r, tmin);

    bool hitSomething = false;
    int i, j, k;
    do {
        mi.getIndices(i, j, k);
        
        printf("The current point is:%d,%d,%d\n", i, j, k);

        if (mObjects[offset(i, j, k)].getNumObjects() > 0) {
            h.set(mi.get_tmin(), m, mi.getNormal(), r);
            return true;
        }

        mi.nextCell();
    } while(i < mXSize && j < mYSize && k < mZSize);
    return false;
}

bool Plane::intersect(const Ray & r, Hit & h, float tmin)
{
	assert (tmin >= 0.0f);

	Vec3f org = r.getOrigin();
	Vec3f dir = r.getDirection();

	if (dir.Dot3(normal) < 1.0e-7 && dir.Dot3(normal) > -1.0e-7) {
		return false;
	}					// Appromately parrell to plane

	float tempT = (offset - org.Dot3(normal)) / dir.Dot3(normal);
	if (tempT <= 1e-6) {
		return false;
	}
	else if (tempT >= tmin && tempT < h.getT()) 
	{
		// Update Hit Point
		normal.Normalize();
		h.set(tempT, NULL, normal, color, r);

		return true;
	}
	
	return false;
}

bool Face::plane_intersect(const Ray &r, Hit &h, bool intersect_backfacing) const {

  // insert the explicit equation for the ray into the implicit equation of the plane

  // equation for a plane
  // ax + by + cz = d;
  // normal . p + direction = 0
  // plug in ray
  // origin + direction * t = p(t)
  // origin . normal + t * direction . normal = d;
  // t = d - origin.normal / direction.normal;

  glm::vec3 normal = computeNormal();
  float d = glm::dot(normal,(*this)[0]->get());

  float numer = d - glm::dot(r.getOrigin(),normal);
  float denom = glm::dot(r.getDirection(),normal);

  if (denom == 0) return 0;  // parallel to plane

  if (!intersect_backfacing && glm::dot(normal,r.getDirection()) >= 0) 
    return 0; // hit the backside

  float t = numer / denom;
  if (t > EPSILON && t < h.getT()) {
    h.set(t,this->getMaterial(),normal);
    assert (h.getT() >= EPSILON);
    return 1;
  }
  return 0;
}

bool Transform::Intersect(const Ray &r, Hit &h, float tmin) const
{
  bool result = false;
  
  Matrix m = m_matrix;
  if ( m.Inverse() )
    {
      Vec3f org = r.getOrigin();
      Vec3f dir = r.getDirection();
      m.Transform(org);
      m.TransformDirection(dir);
      Ray r2 (dir, org);
      result = m_pObject->Intersect(r2, h, tmin);
      
      if (result)
	{
	  Matrix m1 = m;
	  m1.Transpose();
	  Vec3f n = h.getNormal();
	  m1.TransformDirection(n);
	  n.Normalize();
	  h.set(h.getT(), h.getMaterial(), n, r);
	}
    }
  return result;
}

bool Face::plane_intersect(const Ray &r, Hit &h, bool intersect_backfacing, bool* backfacing_hit) {

	// insert the explicit equation for the ray into the implicit equation of the plane

	// equation for a plane
	// ax + by + cz = d;
	// normal . p + direction = 0
	// plug in ray
	// origin + direction * t = p(t)
	// origin . normal + t * direction . normal = d;
	// t = d - origin.normal / direction.normal;

	Vec3f normal = computeNormal();
	double d = normal.Dot3((*this)[0]->get());

	double numer = d - r.getOrigin().Dot3(normal);
	double denom = r.getDirection().Dot3(normal);

	if (denom == 0) return 0;	// parallel to plane

	if (!intersect_backfacing && normal.Dot3(r.getDirection()) >= 0) 
		return 0; // hit the backside

	double t = numer / denom;
	if (t > EPSILON && t < h.getT()) {
		h.set(t,this->getMaterial(),normal,this);
		assert (h.getT() >= EPSILON);
		//hit the backside but that's okay in this case
		if (normal.Dot3(r.getDirection()) >= 0){
			*backfacing_hit = true;
		}
		return 1;
	}
	return 0;
}

bool Sphere::intersect(const Ray &r, Hit &h, float tmin)
{
	//直线方程 P = t*D + R    ①
	//圆方程  ||P||= raduis   ②
	//将①带入②, 由点乘的性质(满足分配率，交换律)，求得t^2+2RDt+R^2-r^2=0
	//得t = -RD±sqrt(RD^2-R^2+r^2)
	//选择距离较近的那个点t = -RD-sqrt(RD^2-R^2+r^2)
	Vec3f D = r.getDirection();
	Vec3f R = r.getOrigin()-center;


	float R2 = R.Dot3(R);
	float RD = R.Dot3(D);
	
	float b2_4ac = RD*RD-R2+radius*radius;//R2 RD RDRD这些其实可以存在ray里，但是算法研究以程序清晰为要
	if(b2_4ac<0)return 0;
	float t;
	t = -RD - sqrt(b2_4ac);
	if(t<0){
		t = -RD + sqrt(b2_4ac);
		if(t < 0)return 0;
	}
	if(t<h.getT())
	{
		h.set(t, &color, r);
	}

	return 1;
}

/*
The intersect routine will first transform the ray, 
then delegate to the intersect routine of the contained 
object. Make sure to correctly transform the resulting 
normal according to the rule seen in lecture. You may 
choose to normalize the direction of the transformed ray 
or leave it un-normalized. If you decide not to normalize 
the direction, you might need to update some of your intersection code.
*/
bool Transform::intersect(const Ray &r, Hit &h, float tmin)
{
	Vec3f r0 = r.getOrigin();
	Vec3f rd = r.getDirection();
	Matrix inv;
	matrix.Inverse(inv);
	inv.Transform(r0);
	inv.TransformDirection(rd);
	if (object != NULL)
	{
		//这里的h是有问题的，作如下修改：
		bool judge = object->intersect(Ray(r0,rd), h, tmin);
		Vec3f normal = h.getNormal();
		//这里很奇怪，normal的方向没有修正，然而结果却是对的
		//改了之后反而是错的！！
		//这里确定normal没有错，那么就是之后应用normal的
		//问题
		//好吧，就是这里的问题
		//经过把图形摆正，发现求的法向量没有问题，但是没有单位化…………！
		matrix.TransformDirection(normal);
		normal.Normalize();
		//or：
		//Matrix change,res;
		//matrix.Inverse(change);
		//change.Transpose(res);
		//res.TransformDirection(normal);
		h.set(h.getT(), h.getMaterial(), normal, r);
		return judge;
	}
	return false;
}

bool Sphere::intersect(const Ray &r, Hit &h, float tmin){

	/*Vector equation for sphere
	P*P - r^2 = 0
	((R0-c) + td)*((R0-c) + td) - r^2 = 0
	(td)^2 + 2R0-c)td + (R0-c)^2 - r^2 =0
	Use quadratic equation solve for t
	a = (d^2)
	b = 2(R0-c)d
    c = ((R0-c)^2 - r^2)
	*/

	Vec3f rayOrigin, rayDirection,segment,Q;
	float tpos,tneg,a,b,c,discriminant;

	rayOrigin = r.getOrigin();
	rayDirection = r.getDirection();
	segment = rayOrigin - _center;

	a = rayDirection.Dot3(rayDirection);
	b = 2*segment.Dot3(rayDirection);
	c = segment.Dot3(segment) - _radius*_radius;

	discriminant = sqrt(b*b - 4*a*c); 

	tpos = (-b + discriminant)/(2*a);
	tneg = (-b - discriminant)/(2*a);

	if (tneg > tmin && tneg < h.getT()){
			Q = r.pointAtParameter(tneg);
			Q = Q - _center;
			Q.Normalize();
			h.set(tneg, _material,Q,r);
			return true;
		}
	else if (tpos > tmin && tpos < h.getT()){
			Q = r.pointAtParameter(tpos);
			Q = Q - _center;
			Q.Normalize();
			h.set(tpos,_material,Q,r);
			return true;
		}
	return false;

}

void Track::extrapolateToLayer0() {
   Int_t nTracks = GetEntriesFast();
   Int_t eventID = -1;

   if (!At(0)) {
      // OK, no information in first layer

      // now GetLayer(1) should be 1, and GetLayer(2) should be 2
      // If both layer 0 and 2 are skipped, some more extrapolation should be done
      // maybe set new x as [1.x - slope.x * (2.z - 1.z)]

      Hit *slope = new Hit();

      if (!At(1)) {
         cout << "No pointer for At(1) as well... Aborting this track extrapolation.\n";
         return;
      }
      else {
         eventID = At(1)->getEventID();
         if (getLayer(1) == 0) return; // hotfix... Why is layer 0 sometimes placed in idx 1? Must fix this.
      }

      if (At(2)) {
         slope->set(getX(2) - getX(1), getY(2) - getY(1), getLayer(2) - getLayer(1));
         if (eventID<0) eventID = At(2)->getEventID();
      }
      else if (!At(2) && At(3)) {
         slope->set(getX(3) - getX(1), getY(3) - getY(1), getLayer(3) - getLayer(1));
         if (eventID<0) eventID = At(3)->getEventID();
      }
      else {
         cout << "Too many holes (!At(0), At(1), !At(2), !At(3), .....), aborting this track extrapolation.\n";
         return;
      }

      // must create pointer!
      Cluster *newStart = (Cluster*) track_.ConstructedAt(0);

      newStart->set(getX(1) - slope->getLayer() * slope->getX(), // new x
                 getY(1) - slope->getLayer() * slope->getY(), // new y
                 0); // layer = 0

      newStart->setEventID(eventID);
   }
}

bool Sphere::intersect(const Ray &r, Hit &h) const {




  // ==========================================
  // ASSIGNMENT:  IMPLEMENT SPHERE INTERSECTION
  // ==========================================

  // a = d (dot) d
  double a = r.getDirection().Dot3(r.getDirection());

  // b = 2d (dot) (orginPoint - centerPoint)
  double b = (2*(r.getDirection())).Dot3(r.getOrigin() - center);

  // c = (p_0 - p_c) dot (p_0-p_c) - r^2
  double c = (r.getOrigin() - center).Dot3(r.getOrigin() - center) - (radius*radius);

  // t = (-b +/- sqrt(b2 - 4 a c)) / (2 a)
  // if inside is negative, then it doesn't intersect the sphere
  // if zero just a slight glance of sphere
  // if two then you interect and leave

  double inside = (b*b) - 4*a*c;

  if(inside >= 0 ){ 
    //inside

    // get the first intersection point
    double t = ((-1*b) - sqrt(inside)) / (2*a);

    if(t < 0) return false;

    // get pt collision
    Vec3f pt = r.getOrigin() + t * r.getDirection();

    if(pt.Distance3f(r.getOrigin()) < EPSILON) return false;


    Vec3f norm((pt.x() - center.x())/radius, (pt.y() - center.y())/radius, (pt.z() - center.z())/radius);
    norm.Normalize();

    h.set(t,getMaterial(),norm);
    return true;

  }else{

    // Negative and therefore missed
    return false;
    
  }

  // return true if the sphere was intersected, and update
  // the hit data structure to contain the value of t for the ray at
  // the intersection point, the material, and the normal
  return false;
} 

bool Triangle::intersect( const Ray& r , Hit& h , float tmin){

	Vector3f R_o = r.getOrigin();
	Vector3f R_d = r.getDirection();

	Matrix3f A( this->a.x()-this->b.x() , this->a.x()-this->c.x() , R_d.x() ,
		    this->a.y()-this->b.y() , this->a.y()-this->c.y() , R_d.y() ,
		    this->a.z()-this->b.z() , this->a.z()-this->c.z() , R_d.z()  );

	Matrix3f BetaM( this->a.x()-R_o.x() , this->a.x()-this->c.x() , R_d.x() ,
		        this->a.y()-R_o.y() , this->a.y()-this->c.y() , R_d.y() ,
		        this->a.z()-R_o.z() , this->a.z()-this->c.z() , R_d.z()  );
	
	float beta = BetaM.determinant() / A.determinant();

	Matrix3f GammaM( this->a.x()-this->b.x() , this->a.x()-R_o.x() , R_d.x() ,
		         this->a.y()-this->b.y() , this->a.y()-R_o.y() , R_d.y() ,
		         this->a.z()-this->b.z() , this->a.z()-R_o.z() , R_d.z()  );
	
	float gamma = GammaM.determinant() / A.determinant();

	float alpha = 1.0f - beta - gamma;

	Matrix3f tM( this->a.x()-this->b.x() , this->a.x()-this->c.x() , this->a.x()-R_o.x() ,
		     this->a.y()-this->b.y() , this->a.y()-this->c.y() , this->a.y()-R_o.y() ,
		     this->a.z()-this->b.z() , this->a.z()-this->c.z() , this->a.z()-R_o.z()  );
	
	float t = tM.determinant() / A.determinant();

	if (beta + gamma > 1){
	    return false;
	} 
	if (beta < 0){
	    return false;
	} 
	if (gamma < 0){
	    return false;
	} 

	if (t > tmin && t < h.getT()){

	    Vector3f newNormal = (alpha*this->normals[0] + beta*this->normals[1] + gamma*this->normals[2]).normalized();
	    h.set(t, this->material, newNormal);

	    Vector2f newTexCoord = (alpha*this->texCoords[0] + beta*this->texCoords[1] + gamma*this->texCoords[2]);
	    h.setTexCoord(newTexCoord);

	    return true;	
	} 
	else{
	    return false;
	} 
}

bool CylinderRing::intersect(const Ray &r, Hit &h) const {

  // intersect with the 4 parts of the ring
  double outer_t;
  Vec3f outer_normal;
  bool outer = IntersectFiniteCylinder(r,center,outer_radius,height,outer_t,outer_normal);
  double inner_t;
  Vec3f inner_normal;
  bool inner = IntersectFiniteCylinder(r,center,inner_radius,height,inner_t,inner_normal);
  double top_t;
  Vec3f top_normal;
  bool top = IntersectAnnulus(r,center+Vec3f(0,height/2.0,0),inner_radius,outer_radius,top_t,top_normal);
  double bottom_t;
  Vec3f bottom_normal;
  bool bottom = IntersectAnnulus(r,center-Vec3f(0,height/2.0,0),inner_radius,outer_radius,bottom_t,bottom_normal);
  bool answer = false;

  // return the closest intersection
  if (outer && (outer_t < h.getT())) {
    h.set(outer_t,this->getMaterial(),outer_normal,NULL);
    answer = true;
  }
  if (inner && (inner_t < h.getT())) {
    h.set(inner_t,this->getMaterial(),-inner_normal,NULL);
    answer = true;
  }
  if (top && (top_t < h.getT())) {
    h.set(top_t,this->getMaterial(),top_normal,NULL);
    answer = true;
  }
  if (bottom && (bottom_t < h.getT())) {
    h.set(bottom_t,this->getMaterial(),-bottom_normal,NULL);
    answer = true;
  }
  return answer;
}