IcoSphere Class Reference

#include <icosphere.h>

Public Member Functions
	IcoSphere (unsigned int levels=1)
const std::vector< Eigen::Vector3f > &	vertices () const
const std::vector< int > &	indices (int level) const
void	draw (int level)

Protected Member Functions
void	_subdivide ()

Protected Attributes
std::vector< Eigen::Vector3f >	mVertices
std::vector< std::vector< int > * >	mIndices
std::vector< int >	mListIds

Constructor & Destructor Documentation

IcoSphere()

IcoSphere::IcoSphere

(

unsigned int

levels = 1

)

                                        {
  // init with an icosahedron
  for (int i = 0; i < 12; i++) mVertices.push_back(Map<Vector3f>(vdata[i]));
  mIndices.push_back(new std::vector<int>);
  std::vector<int>& indices = *mIndices.back();
  for (int i = 0; i < 20; i++) {
    for (int k = 0; k < 3; k++) indices.push_back(tindices[i][k]);
  }
  mListIds.push_back(0);
 
  while (mIndices.size() < levels) _subdivide();
}

References i, k, tindices, and vdata.

Member Function Documentation

_subdivide()

void IcoSphere::_subdivide ( void  )

protected

                               {
  typedef unsigned long long Key;
  std::map<Key, int> edgeMap;
  const std::vector<int>& indices = *mIndices.back();
  mIndices.push_back(new std::vector<int>);
  std::vector<int>& refinedIndices = *mIndices.back();
  int end = indices.size();
  for (int i = 0; i < end; i += 3) {
    int ids0[3],  // indices of outer vertices
        ids1[3];  // indices of edge vertices
    for (int k = 0; k < 3; ++k) {
      int k1 = (k + 1) % 3;
      int e0 = indices[i + k];
      int e1 = indices[i + k1];
      ids0[k] = e0;
      if (e1 > e0) std::swap(e0, e1);
      Key edgeKey = Key(e0) | (Key(e1) << 32);
      std::map<Key, int>::iterator it = edgeMap.find(edgeKey);
      if (it == edgeMap.end()) {
        ids1[k] = mVertices.size();
        edgeMap[edgeKey] = ids1[k];
        mVertices.push_back((mVertices[e0] + mVertices[e1]).normalized());
      } else
        ids1[k] = it->second;
    }
    refinedIndices.push_back(ids0[0]);
    refinedIndices.push_back(ids1[0]);
    refinedIndices.push_back(ids1[2]);
    refinedIndices.push_back(ids0[1]);
    refinedIndices.push_back(ids1[1]);
    refinedIndices.push_back(ids1[0]);
    refinedIndices.push_back(ids0[2]);
    refinedIndices.push_back(ids1[2]);
    refinedIndices.push_back(ids1[1]);
    refinedIndices.push_back(ids1[0]);
    refinedIndices.push_back(ids1[1]);
    refinedIndices.push_back(ids1[2]);
  }
  mListIds.push_back(0);
}

References Eigen::placeholders::end, i, k, and swap().

draw()

void IcoSphere::draw

(

int

level

)

                              {
  while (level >= int(mIndices.size())) const_cast<IcoSphere*>(this)->_subdivide();
  if (mListIds[level] == 0) {
    mListIds[level] = glGenLists(1);
    glNewList(mListIds[level], GL_COMPILE);
    glVertexPointer(3, GL_FLOAT, 0, mVertices[0].data());
    glNormalPointer(GL_FLOAT, 0, mVertices[0].data());
    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_NORMAL_ARRAY);
    glDrawElements(GL_TRIANGLES, mIndices[level]->size(), GL_UNSIGNED_INT, &(mIndices[level]->at(0)));
    glDisableClientState(GL_VERTEX_ARRAY);
    glDisableClientState(GL_NORMAL_ARRAY);
    glEndList();
  }
  glCallList(mListIds[level]);
}

References data, and size.

Referenced by GpuHelper::drawUnitSphere().

indices()

const std::vector< int > & IcoSphere::indices

(

int

level

)

const

                                                        {
  while (level >= int(mIndices.size())) const_cast<IcoSphere*>(this)->_subdivide();
  return *mIndices[level];
}

vertices()

const std::vector<Eigen::Vector3f>& IcoSphere::vertices ( ) const

inline

{ return mVertices; }

References mVertices.

Member Data Documentation

mIndices

std::vector<std::vector<int>*> IcoSphere::mIndices

protected

mListIds

std::vector<int> IcoSphere::mListIds

protected

mVertices

std::vector<Eigen::Vector3f> IcoSphere::mVertices

protected

Referenced by vertices().

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The documentation for this class was generated from the following files:

• icosphere.h
• icosphere.cpp