codebase / stimlib

  #ifndef STIM_CYLINDER_H
  #define STIM_CYLINDER_H
  #include <iostream>
  #include <stim/math/circle.h>

  #include <stim/biomodels/centerline.h>

  #include <stim/visualization/obj.h>

  
  namespace stim
  {
  template<typename T>

  class cylinder : public centerline<T> {
  protected:

  	
  	using stim::centerline<T>::d;

  	std::vector< stim::vec3<T> > U;					//stores the array of U vectors defining the Frenet frame

  	std::vector< T > R;				//stores a list of magnitudes for each point in the centerline (assuming mags[0] is the radius)

  	using stim::centerline<T>::findIdx;

  	//calculates the U values for each point to initialize the frenet frame
  	//	this function assumes that the centerline has already been set
  	void init() {
  		U.resize(size());								//allocate space for the frenet frame vectors

  		R.resize(size());

  	
  		stim::circle<T> c;								//create a circle
  		stim::vec3<T> d0, d1;
  		for (size_t i = 0; i < size() - 1; i++) {		//for each line segment in the centerline
  			c.rotate(d(i));								//rotate the circle to match that normal
  			U[i] = c.U;									//save the U vector from the circle

  		}

  		U[size() - 1] = c.U;							//for the last point, duplicate the final frenet frame vector
  	}
  

  public:

  	using stim::centerline<T>::size;
  	using stim::centerline<T>::at;

  	using stim::centerline<T>::L;
  	using stim::centerline<T>::length;

  	cylinder() : centerline<T>(){}

  	cylinder(centerline<T>c) : centerline<T>(c) {

  		init();

  	}

  	//cylinder(centerline<T>c, T r) : centerline(c) {
  	//	init();
  	//	//add_mag(r);
  	//}
  

  	//initialize a cylinder with a list of points and magnitude values

  	//cylinder(centerline<T>c, std::vector<T> r) : centerline(c){
  	//	init();
  	//	//add_mag(r);
  	//}

  	//copy the original radius
  	void copy_r(std::vector<T> radius) {
  		for (unsigned i = 0; i < radius.size(); i++)
  			R[i] = radius[i];
  	}
  

  	///Returns magnitude i at the given length into the fiber (based on the pvalue).
  	///Interpolates the position along the line.
  	///@param l: the location of the in the cylinder.
  	///@param idx: integer location of the point closest to l but prior to it.

  	T r(T l, int idx) {

  		T a = (l - L[idx]) / (L[idx + 1] - L[idx]);

  		T v2 = (R[idx] + (R[idx + 1] - R[idx])*a);

  		
  		return v2;
  	}
  
  	///Returns the ith magnitude at the given p-value (p value ranges from 0 to 1).
  	///interpolates the radius along the line.
  	///@param pvalue: the location of the in the cylinder, from 0 (beginning to 1).

  	T rl(T pvalue) {

  		if (pvalue <= 0.0) return R[0];
  		if (pvalue >= 1.0) return R[size() - 1];

  
  		T l = pvalue*L[L.size() - 1];
  		int idx = findIdx(l);

  		return r(l, idx);

  	}
  

  	///	Returns the magnitude at the given index
  	///	@param i is the index of the desired point

  	/// @param r is the index of the magnitude value

  	T r(unsigned i) {
  		return R[i];
  	}

  
  	///adds a magnitude to each point in the cylinder

  	/*void add_mag(V val = 0) {

  		if (M.size() == 0) M.resize(size());	//if the magnitude vector isn't initialized, resize it to match the centerline
  		for (size_t i = 0; i < size(); i++)		//for each point

  			R[i].push_back(val);				//add this value to the magnitude vector at each point
  	}*/

  
  	//adds a magnitude based on a list of magnitudes for each point

  	/*void add_mag(std::vector<T> val) {

  		if (M.size() == 0) M.resize(size());	//if the magnitude vector isn't initialized, resize it to match the centerline
  		for (size_t i = 0; i < size(); i++)		//for each point

  			R[i].push_back(val[i]);				//add this value to the magnitude vector at each point
  	}*/

  
  	//sets the value of magnitude m at point i

  	void set_r(size_t i, T r) {
  		R[i] = r;

  	}
  

  	/*size_t nmags() {

  		if (M.size() == 0) return 0;

  		else return R[0].size();
  	}*/

  	///Returns a circle representing the cylinder cross section at point i

  	stim::circle<T> circ(size_t i) {
  		return stim::circle<T>(at(i), R[i], d(i), U[i]);

  	}
  
  	///Returns an OBJ object representing the cylinder with a radial tesselation value of N using magnitude m

  	stim::obj<T> OBJ(size_t N) {

  		stim::obj<T> out;								//create an OBJ object
  		stim::circle<T> c0, c1;
  		std::vector< stim::vec3<T> > p0, p1;			//allocate space for the point sets representing the circles bounding each cylinder segment
  		T u0, u1, v0, v1;											//allocate variables to store running texture coordinates
  		for (size_t i = 1; i < size(); i++) {			//for each line segment in the cylinder
  			c0 = circ(i - 1);							//get the two circles bounding the line segment
  			c1 = circ(i);
  
  			p0 = c0.points(N);							//get t points for each of the end caps
  			p1 = c1.points(N);
  
  			u0 = L[i - 1] / length();						//calculate the texture coordinate (u, v) where u runs along the cylinder length
  			u1 = L[i] / length();
  				
  			for (size_t n = 1; n < N; n++) {				//for each point in the circle
  				v0 = (double)(n-1) / (double)(N - 1);			//v texture coordinate runs around the cylinder
  				v1 = (double)(n) / (double)(N - 1);
  				out.Begin(OBJ_FACE);						//start a face (quad)
  					out.TexCoord(u0, v0);
  					out.Vertex(p0[n - 1][0], p0[n - 1][1], p0[n - 1][2]);	//output the points composing a strip of quads wrapping the cylinder segment
  					out.TexCoord(u1, v0);
  					out.Vertex(p1[n - 1][0], p1[n - 1][1], p1[n - 1][2]);
  				
  					out.TexCoord(u0, v1);
  					out.Vertex(p1[n][0], p1[n][1], p1[n][2]);
  					out.TexCoord(u1, v1);
  					out.Vertex(p0[n][0], p0[n][1], p0[n][2]);
  				out.End();

  			}

  			v0 = (double)(N - 2) / (double)(N - 1);			//v texture coordinate runs around the cylinder
  			v1 = 1.0;
  			out.Begin(OBJ_FACE);
  				out.TexCoord(u0, v0);
  				out.Vertex(p0[N - 1][0], p0[N - 1][1], p0[N - 1][2]);	//output the points composing a strip of quads wrapping the cylinder segment
  				out.TexCoord(u1, v0);
  				out.Vertex(p1[N - 1][0], p1[N - 1][1], p1[N - 1][2]);
  
  				out.TexCoord(u0, v1);
  				out.Vertex(p1[0][0], p1[0][1], p1[0][2]);
  				out.TexCoord(u1, v1);
  				out.Vertex(p0[0][0], p0[0][1], p0[0][2]);
  			out.End();
  		}
  		return out;
  	}

  	std::string str() {
  		std::stringstream ss;
  		size_t N = std::vector< stim::vec3<T> >::size();
  		ss << "---------[" << N << "]---------" << std::endl;
  		for (size_t i = 0; i < N; i++)

  			ss << std::vector< stim::vec3<T> >::at(i) << "   r = " << R[i] << "   u = " << U[i] << std::endl;

  		ss << "--------------------" << std::endl;
  
  		return ss.str();
  	}
  
  	/// Integrates a magnitude value along the cylinder.
  	/// @param m is the magnitude value to be integrated (this is usually the radius)

  	T integrate() {

  		T sum = 0;							//initialize the integral to zero
  		if (L.size() == 1)
  			return sum;
  		else {					
  			T m0, m1;						//allocate space for both magnitudes in a single segment
  			m0 = R[0];					//initialize the first point and magnitude to the first point in the cylinder
  			T len = L[1];					//allocate space for the segment length
  
  
  			for (unsigned p = 1; p < size(); p++) {				//for every consecutive point in the cylinder
  				m1 = R[p];
  				if (p > 1) len = (L[p] - L[p - 1]);		//calculate the segment length using the L array
  				sum += (m0 + m1) / (T)2.0 * len;				//add the average magnitude, weighted by the segment length
  				m0 = m1;									//move to the next segment by shifting points
  			}
  			return sum;			//return the integral

  		}

  	}
  
  	/// Resamples the cylinder to provide a maximum distance of "spacing" between centerline points. All current
  	///		centerline points are guaranteed to exist in the new cylinder
  	/// @param spacing is the maximum spacing allowed between sample points
  	cylinder<T> resample(T spacing) {
  		cylinder<T> c = stim::centerline<T>::resample(spacing);			//resample the centerline and use it to create a new cylinder
  

  		//size_t nm = nmags();											//get the number of magnitude values in the current cylinder
  		//if (nm > 0) {													//if there are magnitude values
  		//	std::vector<T> magvec(nm, 0);							//create a magnitude vector for a single point
  		//	c.M.resize(c.size(), magvec);									//allocate space for a magnitude vector at each point of the new cylinder
  		//}

  
  		T l, t;
  		for (size_t i = 0; i < c.size(); i++) {							//for each point in the new cylinder
  			l = c.L[i];													//get the length along the new cylinder
  			t = l / length();										//calculate the parameter value along the new cylinder

  			//for (size_t mag = 0; mag < nm; mag++) {							//for each magnitude value
  			c.R[i] = r(t);								//retrieve the interpolated magnitude from the current cylinder and store it in the new one
  			//}

  		}

  		return c;
  	}

  	std::vector< stim::cylinder<T> > split(unsigned int idx) {
  
  		unsigned N = size();
  		std::vector< stim::centerline<T> > LL;
  		LL.resize(2);
  		LL = (*this).centerline<T>::split(idx);
  		std::vector< stim::cylinder<T> > C(LL.size());
  		unsigned i = 0;
  		C[0] = LL[0];
  		//C[0].R.resize(idx);

  		for (; i < idx + 1; i++) {

  			//for(unsigned d = 0; d < 3; d++)
  			//C[0][i][d] = LL[0].c[i][d];
  			C[0].R[i] = R[i];
  			//C[0].R[i].resize(1);
  		}
  		if (C.size() == 2) {
  			C[1] = LL[1];

  			i--;

  			//C[1].M.resize(N - idx);
  			for (; i < N; i++) {
  				//for(unsigned d = 0; d < 3; d++)
  				//C[1][i - idx][d] = LL[1].c[i - idx][d];
  				C[1].R[i - idx] = R[i];
  				//C[1].M[i - idx].resize(1);
  			}
  		}

  		return C;

  	}
  

  
  		/*
  		///inits the cylinder from a list of points (std::vector of stim::vec3 --inP) and magnitudes (inM)

  		void

  		init(centerline inP, std::vector< std::vector<T> > inM) {
  			M = inM;									//the magnitude vector can be copied directly
  			(*this) = inP;								//the centerline can be copied to this class directly

  			stim::vec3<float> v1;
  			stim::vec3<float> v2;

  			e.resize(inP.size());

  
  			norms.resize(inP.size());
  			Us.resize(inP.size());
  

  			if(inP.size() < 2)
  				return;

  
  			//calculate each L.

  			L.resize(inP.size());						//the number of precomputed lengths will equal the number of points
  			T temp = (T)0;								//length up to that point
  			L[0] = temp;

  			for(size_t i = 1; i < L.size(); i++)

  			{

  				temp += (inP[i-1] - inP[i]).len();

  				L[i] = temp;

  			}

  			stim::vec3<T> dr = (inP[1] - inP[0]).norm();

  			s = stim::circle<T>(inP[0], inR[0][0], dr, stim::vec3<T>(1,0,0));

  			norms[0] = s.N;

  			e[0] = s;

  			Us[0] = e[0].U;

  			for(size_t i = 1; i < inP.size()-1; i++)

  			{
  				s.center(inP[i]);
  				v1 = (inP[i] - inP[i-1]).norm();
  				v2 = (inP[i+1] - inP[i]).norm();
  				dr = (v1+v2).norm();
  				s.normal(dr);

  
  				norms[i] = s.N;
  

  				s.scale(inR[i][0]/inR[i-1][0]);

  				e[i] = s;

  				Us[i] = e[i].U;

  			}
  			
  			int j = inP.size()-1;
  			s.center(inP[j]);
  			dr = (inP[j] - inP[j-1]).norm();
  			s.normal(dr);

  
  			norms[j] = s.N;
  

  			s.scale(inR[j][0]/inR[j-1][0]);

  			e[j] = s;

  			Us[j] = e[j].U;

  		}
  		

  		///returns the direction vector at point idx.

  		stim::vec3<T>

  		d(int idx)
  		{
  			if(idx == 0)
  			{

  				stim::vec3<T> temp(
  						c[idx+1][0]-c[idx][0],	
  						c[idx+1][1]-c[idx][1],	
  						c[idx+1][2]-c[idx][2]
  						);	
  //				return (e[idx+1].P - e[idx].P).norm();
  				return (temp.norm());

  			}

  			else if(idx == N-1)

  			{

  				stim::vec3<T> temp(
  						c[idx][0]-c[idx+1][0],	
  						c[idx][1]-c[idx+1][1],	
  						c[idx][2]-c[idx+1][2]
  						);	
  			//	return (e[idx].P - e[idx-1].P).norm();
  				return (temp.norm());

  			}
  			else
  			{

  //				return (e[idx+1].P - e[idx].P).norm();

  //				stim::vec3<float> v1 = (e[idx].P-e[idx-1].P).norm();
  				stim::vec3<T> v1(
  						c[idx][0]-c[idx-1][0],	
  						c[idx][1]-c[idx-1][1],	
  						c[idx][2]-c[idx-1][2]
  						);	
  						
  //				stim::vec3<float> v2 = (e[idx+1].P-e[idx].P).norm();
  				stim::vec3<T> v2(
  						c[idx+1][0]-c[idx][0],	
  						c[idx+1][1]-c[idx][1],	
  						c[idx+1][2]-c[idx][2]
  						);
  					
  				return (v1.norm()+v2.norm()).norm();			

  			} 
  	//		return e[idx].N;	
  

  		}
  

  		stim::vec3<T>

  		d(T l, int idx)

  		{

  			if(idx == 0 || idx == N-1)

  			{

  				return norms[idx];
  //				return e[idx].N;

  			}

  			else
  			{

  				T rat = (l-L[idx])/(L[idx+1]-L[idx]);

  				return(	norms[idx] + (norms[idx+1] - norms[idx])*rat);
  //				return(	e[idx].N + (e[idx+1].N - e[idx].N)*rat);

  			} 

  		}
  

  		///finds the index of the point closest to the length l on the lower bound.
  		///binary search.

  		int

  		findIdx(T l)
  		{
  			unsigned int i = L.size()/2;
  			unsigned int max = L.size()-1;
  			unsigned int min = 0;

  			while(i > 0 && i < L.size()-1)

  			{

  //				std::cerr << "Trying " << i << std::endl;
  //				std::cerr << "l is " << l << ", L[" << i << "]" << L[i] << std::endl;

  				if(l < L[i])

  				{

  					max = i;

  					i = min+(max-min)/2;

  				}

  				else if(L[i] <= l && L[i+1] >= l)

  				{
  					break;
  				}
  				else
  				{

  					min = i;

  					i = min+(max-min)/2;

  				}
  			}
  			return i;
  		}

  	public:
  		///default constructor

  		cylinder()

  		// : centerline<T>()

  		{
  
  		}

  		///constructor to create a cylinder from a set of points, radii, and the number of sides for the cylinder.

  		///@param inP:  Vector of stim vec3 composing the points of the centerline.

  		///@param inM:  Vector of stim vecs composing the radii of the centerline.

  		cylinder(std::vector<stim::vec3<T> > inP, std::vector<stim::vec<T> > inM)
  			: centerline<T>(inP)
  		{

  			init(inP, inM);
  		}
  

  		///constructor to create a cylinder from a set of points, radii, and the number of sides for the cylinder.
  		///@param inP:  Vector of stim vec3 composing the points of the centerline.
  		///@param inM:  Vector of stim vecs composing the radii of the centerline.
  		cylinder(std::vector<stim::vec3<T> > inP, std::vector< T > inM)
  			: centerline<T>(inP)
  		{
  			std::vector<stim::vec<T> > temp;

  			stim::vec<T> zero(0.0,0.0);

  			temp.resize(inM.size(), zero);

  			for(int i = 0; i < inM.size(); i++)

  				temp[i][0] = inR[i];

  			init(inP, temp);
  		}
  

  		///Constructor defines a cylinder with centerline inP and magnitudes of zero

  		///@param inP: Vector of stim vec3 composing the points of the centerline

  		cylinder(std::vector< stim::vec3<T> > inP)
  			: centerline<T>(inP)
  		{

  			std::vector< stim::vec<T> > inM;						//create an array of arbitrary magnitudes

  
  			stim::vec<T> zero;
  			zero.push_back(0);
  
  			inM.resize(inP.size(), zero);								//initialize the magnitude values to zero

  			init(inP, inM);
  		}
  

  		//assignment operator creates a cylinder from a centerline (default radius is zero)
  		cylinder& operator=(stim::centerline<T> c) {
  			init(c);
  		}
  

  		///Returns the number of points on the cylinder centerline
  
  		unsigned int size(){

  			return N;

  		}
  

  		///Returns a position vector at the given p-value (p value ranges from 0 to 1).

  		///interpolates the position along the line.
  		///@param pvalue: the location of the in the cylinder, from 0 (beginning to 1).

  		stim::vec3<T>

  		p(T pvalue)
  		{

  			if(pvalue < 0.0 || pvalue > 1.0)

  			{

  				return stim::vec3<float>(-1,-1,-1);

  			}

  			T l = pvalue*L[L.size()-1];
  			int idx = findIdx(l);

  			return (p(l,idx));

  		}

  		///Returns a position vector at the given length into the fiber (based on the pvalue).
  		///Interpolates the radius along the line.
  		///@param l: the location of the in the cylinder.
  		///@param idx: integer location of the point closest to l but prior to it.

  		stim::vec3<T>

  		p(T l, int idx)
  		{
  				T rat = (l-L[idx])/(L[idx+1]-L[idx]);

  				stim::vec3<T> v1(
  						c[idx][0],	
  						c[idx][1],	
  						c[idx][2]
  						);	
  						
  				stim::vec3<T> v2(
  						c[idx+1][0],	
  						c[idx+1][1],	
  						c[idx+1][2]
  						);
  //			return(	e[idx].P + (e[idx+1].P-e[idx].P)*rat);
  			return(	v1 + (v2-v1)*rat);

  //			return(
  //			return (pos[idx] + (pos[idx+1]-pos[idx])*((l-L[idx])/(L[idx+1]- L[idx])));

  		}
  
  		///Returns a radius at the given p-value (p value ranges from 0 to 1).

  		///interpolates the radius along the line.
  		///@param pvalue: the location of the in the cylinder, from 0 (beginning to 1).

  		T

  		r(T pvalue)
  		{

  			if(pvalue < 0.0 || pvalue > 1.0){
  				std::cerr<<"Error, value "<<pvalue<<" is outside of [0 1]."<<std::endl;
  				exit(1);
  			}

  			T l = pvalue*L[L.size()-1];
  			int idx = findIdx(l);