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bodies.cpp

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#include "geometric_shapes/bodies.h"

#include <ros/console.h>
#include <LinearMath/btConvexHull.h>
// #include <BulletCollision/CollisionShapes/btTriangleShape.h>
#include <algorithm>
#include <iostream>
#include <cmath>

bodies::Body* bodies::createBodyFromShape(const shapes::Shape *shape)
{
  Body *body = NULL;
    
  if (shape)
    switch (shape->type)
    {
    case shapes::BOX:
      body = new bodies::Box(shape);
      break;
    case shapes::SPHERE:
      body = new bodies::Sphere(shape);
      break;
    case shapes::CYLINDER:
      body = new bodies::Cylinder(shape);
      break;
    case shapes::MESH:
      body = new bodies::ConvexMesh(shape);
      break;
    default:
      ROS_ERROR("Creating body from shape: Unknown shape type %d", (int)shape->type);
      break;
    }
    
  return body;
}

void bodies::mergeBoundingSpheres(const std::vector<BoundingSphere> &spheres, BoundingSphere &mergedSphere)
{
  if (spheres.empty())
  {
    mergedSphere.center.setValue(btScalar(0), btScalar(0), btScalar(0));
    mergedSphere.radius = 0.0;
  }
  else
  {
    mergedSphere = spheres[0];
    for (unsigned int i = 1 ; i < spheres.size() ; ++i)
    {
      if (spheres[i].radius <= 0.0)
        continue;
      double d = spheres[i].center.distance(mergedSphere.center);
      if (d + mergedSphere.radius <= spheres[i].radius)
      {
        mergedSphere.center = spheres[i].center;
        mergedSphere.radius = spheres[i].radius;
      }
      else
        if (d + spheres[i].radius > mergedSphere.radius)
        {
          btVector3 delta = mergedSphere.center - spheres[i].center;
          mergedSphere.radius = (delta.length() + spheres[i].radius + mergedSphere.radius)/2.0;
          mergedSphere.center = delta.normalized() * (mergedSphere.radius - spheres[i].radius) + spheres[i].center;
        }
    }
  }
}

namespace bodies
{
static const double ZERO = 1e-9;
    
static inline double distanceSQR(const btVector3& p, const btVector3& origin, const btVector3& dir)
{
  btVector3 a = p - origin;
  double d = dir.dot(a);
  return a.length2() - d * d;
}
    
namespace detail
{
        
// temp structure for intersection points (used for ordering them)
struct intersc
{
  intersc(const btVector3 &_pt, const double _tm) : pt(_pt), time(_tm) {}
            
  btVector3 pt;
  double    time;
};
        
// define order on intersection points
struct interscOrder
{
  bool operator()(const intersc &a, const intersc &b) const
  {
    return a.time < b.time;
  }
};
}
}

bool bodies::Sphere::containsPoint(const btVector3 &p, bool verbose) const 
{
  return (m_center - p).length2() < m_radius2;
}

void bodies::Sphere::useDimensions(const shapes::Shape *shape) // radius
{
  m_radius = static_cast<const shapes::Sphere*>(shape)->radius;
}

void bodies::Sphere::updateInternalData(void)
{
  m_radiusU = m_radius * m_scale + m_padding;
  m_radius2 = m_radiusU * m_radiusU;
  m_center = m_pose.getOrigin();
}

double bodies::Sphere::computeVolume(void) const
{
  return 4.0 * M_PI * m_radiusU * m_radiusU * m_radiusU / 3.0;
}

void bodies::Sphere::computeBoundingSphere(BoundingSphere &sphere) const
{
  sphere.center = m_center;
  sphere.radius = m_radiusU;
}

void bodies::Sphere::computeBoundingCylinder(BoundingCylinder &cylinder) const 
{
  cylinder.pose = m_pose;
  cylinder.radius = m_radiusU;
  cylinder.length = m_radiusU;

}

bool bodies::Sphere::intersectsRay(const btVector3& origin, const btVector3& dir, std::vector<btVector3> *intersections, unsigned int count) const
{
  if (distanceSQR(m_center, origin, dir) > m_radius2) return false;
    
  bool result = false;
    
  btVector3 cp = origin - m_center;
  double dpcpv = cp.dot(dir);
    
  btVector3 w = cp - dpcpv * dir;
  btVector3 Q = m_center + w;
  double x = m_radius2 - w.length2();
    
  if (fabs(x) < ZERO)
  { 
    w = Q - origin;
    double dpQv = w.dot(dir);
    if (dpQv > ZERO)
    {
      if (intersections)
        intersections->push_back(Q);
      result = true;
    }
  } else 
    if (x > 0.0)
    {    
      x = sqrt(x);
      w = dir * x;
      btVector3 A = Q - w;
      btVector3 B = Q + w;
      w = A - origin;
      double dpAv = w.dot(dir);
      w = B - origin;
      double dpBv = w.dot(dir);
            
      if (dpAv > ZERO)
      { 
        result = true;
        if (intersections)
        {
          intersections->push_back(A);
          if (count == 1)
            return result;
        }
      }
            
      if (dpBv > ZERO)
      {
        result = true;
        if (intersections)
          intersections->push_back(B);
      }
    }
  return result;
}

bool bodies::Cylinder::containsPoint(const btVector3 &p, bool verbose) const 
{
  btVector3 v = p - m_center;           
  double pH = v.dot(m_normalH);
    
  if (fabs(pH) > m_length2)
    return false;
    
  double pB1 = v.dot(m_normalB1);
  double remaining = m_radius2 - pB1 * pB1;
    
  if (remaining < 0.0)
    return false;
  else
  {
    double pB2 = v.dot(m_normalB2);
    return pB2 * pB2 < remaining;
  }             
}

void bodies::Cylinder::useDimensions(const shapes::Shape *shape) // (length, radius)
{
  m_length = static_cast<const shapes::Cylinder*>(shape)->length;
  m_radius = static_cast<const shapes::Cylinder*>(shape)->radius;
}

void bodies::Cylinder::updateInternalData(void)
{
  m_radiusU = m_radius * m_scale + m_padding;
  m_radius2 = m_radiusU * m_radiusU;
  m_length2 = m_scale * m_length / 2.0 + m_padding;
  m_center = m_pose.getOrigin();
  m_radiusBSqr = m_length2 * m_length2 + m_radius2;
  m_radiusB = sqrt(m_radiusBSqr);
    
  const btMatrix3x3& basis = m_pose.getBasis();
  m_normalB1 = basis.getColumn(0);
  m_normalB2 = basis.getColumn(1);
  m_normalH  = basis.getColumn(2);
    
  double tmp = -m_normalH.dot(m_center);
  m_d1 = tmp + m_length2;
  m_d2 = tmp - m_length2;
}

double bodies::Cylinder::computeVolume(void) const
{
  return 2.0 * M_PI * m_radius2 * m_length2;
}

void bodies::Cylinder::computeBoundingSphere(BoundingSphere &sphere) const
{
  sphere.center = m_center;
  sphere.radius = m_radiusB;
}

void bodies::Cylinder::computeBoundingCylinder(BoundingCylinder &cylinder) const
{
  cylinder.pose = m_pose;
  cylinder.radius = m_radiusU;
  cylinder.length = m_scale*m_length+m_padding;
}

bool bodies::Cylinder::intersectsRay(const btVector3& origin, const btVector3& dir, std::vector<btVector3> *intersections, unsigned int count) const
{
  if (distanceSQR(m_center, origin, dir) > m_radiusBSqr) return false;

  std::vector<detail::intersc> ipts;
    
  // intersect bases
  double tmp = m_normalH.dot(dir);
  if (fabs(tmp) > ZERO)
  {
    double tmp2 = -m_normalH.dot(origin);
    double t1 = (tmp2 - m_d1) / tmp;
        
    if (t1 > 0.0)
    {
      btVector3 p1(origin + dir * t1);
      btVector3 v1(p1 - m_center);
      v1 = v1 - m_normalH.dot(v1) * m_normalH;
      if (v1.length2() < m_radius2 + ZERO)
      {
        if (intersections == NULL)
          return true;
                
        detail::intersc ip(p1, t1);
        ipts.push_back(ip);
      }
    }
        
    double t2 = (tmp2 - m_d2) / tmp;
    if (t2 > 0.0)
    {
      btVector3 p2(origin + dir * t2);
      btVector3 v2(p2 - m_center);
      v2 = v2 - m_normalH.dot(v2) * m_normalH;
      if (v2.length2() < m_radius2 + ZERO)
      {
        if (intersections == NULL)
          return true;
                
        detail::intersc ip(p2, t2);
        ipts.push_back(ip);
      }
    }
  }
    
  if (ipts.size() < 2)
  {
    // intersect with infinite cylinder
    btVector3 VD(m_normalH.cross(dir));
    btVector3 ROD(m_normalH.cross(origin - m_center));
    double a = VD.length2();
    double b = 2.0 * ROD.dot(VD);
    double c = ROD.length2() - m_radius2;
    double d = b * b - 4.0 * a * c;
    if (d > 0.0 && fabs(a) > ZERO)
    {
      d = sqrt(d);
      double e = -a * 2.0;
      double t1 = (b + d) / e;
      double t2 = (b - d) / e;
            
      if (t1 > 0.0)
      {
        btVector3 p1(origin + dir * t1);
        btVector3 v1(m_center - p1);
                
        if (fabs(m_normalH.dot(v1)) < m_length2 + ZERO)
        {
          if (intersections == NULL)
            return true;
                    
          detail::intersc ip(p1, t1);
          ipts.push_back(ip);
        }
      }
            
      if (t2 > 0.0)
      {
        btVector3 p2(origin + dir * t2);    
        btVector3 v2(m_center - p2);
                
        if (fabs(m_normalH.dot(v2)) < m_length2 + ZERO)
        {
          if (intersections == NULL)
            return true;
          detail::intersc ip(p2, t2);
          ipts.push_back(ip);
        }
      }
    }
  }
    
  if (ipts.empty())
    return false;

  std::sort(ipts.begin(), ipts.end(), detail::interscOrder());
  const unsigned int n = count > 0 ? std::min<unsigned int>(count, ipts.size()) : ipts.size();
  for (unsigned int i = 0 ; i < n ; ++i)
    intersections->push_back(ipts[i].pt);
    
  return true;
}

bool bodies::Box::containsPoint(const btVector3 &p, bool verbose) const 
{
  /*  if(verbose)
      fprintf(stderr,"Actual: %f,%f,%f \nDesired: %f,%f,%f \nTolerance:%f,%f,%f\n",p.x(),p.y(),p.z(),m_center.x(),m_center.y(),m_center.z(),m_length2,m_width2,m_height2);*/
  btVector3 v = p - m_center;
  double pL = v.dot(m_normalL);
    
  if (fabs(pL) > m_length2)
    return false;
    
  double pW = v.dot(m_normalW);
    
  if (fabs(pW) > m_width2)
    return false;
    
  double pH = v.dot(m_normalH);
    
  if (fabs(pH) > m_height2)
    return false;
    
  return true;
}

void bodies::Box::useDimensions(const shapes::Shape *shape) // (x, y, z) = (length, width, height)
{
  const double *size = static_cast<const shapes::Box*>(shape)->size;
  m_length = size[0];
  m_width  = size[1];
  m_height = size[2];
}

void bodies::Box::updateInternalData(void) 
{
  double s2 = m_scale / 2.0;
  m_length2 = m_length * s2 + m_padding;
  m_width2  = m_width * s2 + m_padding;
  m_height2 = m_height * s2 + m_padding;
    
  m_center  = m_pose.getOrigin();
    
  m_radius2 = m_length2 * m_length2 + m_width2 * m_width2 + m_height2 * m_height2;
  m_radiusB = sqrt(m_radius2);

  const btMatrix3x3& basis = m_pose.getBasis();
  m_normalL = basis.getColumn(0);
  m_normalW = basis.getColumn(1);
  m_normalH = basis.getColumn(2);

  const btVector3 tmp(m_normalL * m_length2 + m_normalW * m_width2 + m_normalH * m_height2);
  m_corner1 = m_center - tmp;
  m_corner2 = m_center + tmp;
}

double bodies::Box::computeVolume(void) const
{
  return 8.0 * m_length2 * m_width2 * m_height2;
}

void bodies::Box::computeBoundingSphere(BoundingSphere &sphere) const
{
  sphere.center = m_center;
  sphere.radius = m_radiusB;
}

void bodies::Box::computeBoundingCylinder(BoundingCylinder &cylinder) const
{
  double a, b;
  
  if(m_length2 > m_width2 && m_length2 > m_height2) {
    cylinder.length = m_length2*2.0;
    a = m_width2;
    b = m_height2;
    btTransform rot(btQuaternion(btVector3(0,1,0),btRadians(90)));
    cylinder.pose = m_pose*rot;
  } else if(m_width2 > m_height2) {
    cylinder.length = m_width2*2.0;
    a = m_height2;
    b = m_length2;
    cylinder.radius = sqrt(m_height2*m_height2+m_length2*m_length2);
    btTransform rot(btQuaternion(btVector3(1,0,0),btRadians(90)));
    cylinder.pose = m_pose*rot;
  } else {
    cylinder.length = m_height2*2.0;
    a = m_width2;
    b = m_length2;
    cylinder.pose = m_pose;
  }
  cylinder.radius = sqrt((a)*(a)+(b)*(b));
  //cylinder.radius = sqrt(2*(max_rad*max_rad));
}

bool bodies::Box::intersectsRay(const btVector3& origin, const btVector3& dir, std::vector<btVector3> *intersections, unsigned int count) const
{  
  if (distanceSQR(m_center, origin, dir) > m_radius2) return false;

  double t_near = -INFINITY;
  double t_far  = INFINITY;
    
  for (int i = 0; i < 3; i++)
  {
    const btVector3 &vN = i == 0 ? m_normalL : (i == 1 ? m_normalW : m_normalH);
    double dp = vN.dot(dir);
        
    if (fabs(dp) > ZERO)
    {
      double t1 = vN.dot(m_corner1 - origin) / dp;
      double t2 = vN.dot(m_corner2 - origin) / dp;
            
      if (t1 > t2)
        std::swap(t1, t2);
            
      if (t1 > t_near)
        t_near = t1;
            
      if (t2 < t_far)
        t_far = t2;
            
      if (t_near > t_far)
        return false;
            
      if (t_far < 0.0)
        return false;
    }
    else
    {
      if (i == 0)
      {
        if ((std::min(m_corner1.y(), m_corner2.y()) > origin.y() ||
             std::max(m_corner1.y(), m_corner2.y()) < origin.y()) && 
            (std::min(m_corner1.z(), m_corner2.z()) > origin.z() ||
             std::max(m_corner1.z(), m_corner2.z()) < origin.z()))
          return false;
      }
      else
      {
        if (i == 1)
        {
          if ((std::min(m_corner1.x(), m_corner2.x()) > origin.x() ||
               std::max(m_corner1.x(), m_corner2.x()) < origin.x()) && 
              (std::min(m_corner1.z(), m_corner2.z()) > origin.z() ||
               std::max(m_corner1.z(), m_corner2.z()) < origin.z()))
            return false;
        }
        else
          if ((std::min(m_corner1.x(), m_corner2.x()) > origin.x() ||
               std::max(m_corner1.x(), m_corner2.x()) < origin.x()) && 
              (std::min(m_corner1.y(), m_corner2.y()) > origin.y() ||
               std::max(m_corner1.y(), m_corner2.y()) < origin.y()))
            return false;
      }
    }
  }
    
  if (intersections)
  {
    if (t_far - t_near > ZERO)
    {
      intersections->push_back(t_near * dir + origin);
      if (count > 1)
        intersections->push_back(t_far  * dir + origin);
    }
    else
      intersections->push_back(t_far * dir + origin);
  }
    
  return true;
}
/*
  bool bodies::Mesh::containsPoint(const btVector3 &p) const
  {
  // compute all intersections
  std::vector<btVector3> pts;
  intersectsRay(p, btVector3(0, 0, 1), &pts);
    
  // if we have an odd number of intersections, we are inside
  return pts.size() % 2 == 1;
  }

  namespace bodies
  {
  namespace detail
  {
  // callback for bullet 
  class myTriangleCallback : public btTriangleCallback
  {
  public:
            
  myTriangleCallback(bool keep_triangles) : keep_triangles_(keep_triangles)
  {
  found_intersections = false;
  }
            
  virtual void processTriangle(btVector3 *triangle, int partId, int triangleIndex)
  {
  found_intersections = true;
  if (keep_triangles_)
  triangles.push_back(btTriangleShape(triangle[0], triangle[1], triangle[2]));
  }
            
  bool                         found_intersections;
  std::vector<btTriangleShape> triangles;
            
  private:
            
  bool                         keep_triangles_;
  };

  }
  }

  bool bodies::Mesh::intersectsRay(const btVector3& origin, const btVector3& dir, std::vector<btVector3> *intersections, unsigned int count) const
  {
  if (m_btMeshShape)
  {
        
  if (distanceSQR(m_center, origin, dir) > m_radiusBSqr) return false;
        
  // transform the ray into the coordinate frame of the mesh
  btVector3 orig(m_iPose * origin);
  btVector3 dr(m_iPose.getBasis() * dir);
        
  // find intersection with AABB
  btScalar maxT = 0.0;
        
  if (fabs(dr.x()) > ZERO)
  {
  btScalar t = (m_aabbMax.x() - orig.x()) / dr.x();
  if (t < 0.0)
  t = (m_aabbMin.x() - orig.x()) / dr.x();
  if (t > maxT)
  maxT = t;
  }
  if (fabs(dr.y()) > ZERO)
  {
  btScalar t = (m_aabbMax.y() - orig.y()) / dr.y();
  if (t < 0.0)
  t = (m_aabbMin.y() - orig.y()) / dr.y();
  if (t > maxT)
  maxT = t;
  }
  if (fabs(dr.z()) > ZERO)
  {
  btScalar t = (m_aabbMax.z() - orig.z()) / dr.z();
  if (t < 0.0)
  t = (m_aabbMin.z() - orig.z()) / dr.z();
  if (t > maxT)
  maxT = t;
  }
        
  // the farthest point where we could have an intersection id orig + dr * maxT
        
  detail::myTriangleCallback cb(intersections != NULL);
  m_btMeshShape->performRaycast(&cb, orig, orig + dr * maxT);
  if (cb.found_intersections)
  {
  if (intersections)
  {
  std::vector<detail::intersc> intpt;
  for (unsigned int i = 0 ; i < cb.triangles.size() ; ++i)
  {
  btVector3 normal;
  cb.triangles[i].calcNormal(normal);
  btScalar dv = normal.dot(dr);
  if (fabs(dv) > 1e-3)
  {
  double t = (normal.dot(cb.triangles[i].getVertexPtr(0)) - normal.dot(orig)) / dv;                     
  // here we use the input origin & direction, since the transform is linear
  detail::intersc ip(origin + dir * t, t);
  intpt.push_back(ip);
  }
  }
  std::sort(intpt.begin(), intpt.end(), detail::interscOrder());
  const unsigned int n = count > 0 ? std::min<unsigned int>(count, intpt.size()) : intpt.size();
  for (unsigned int i = 0 ; i < n ; ++i)
  intersections->push_back(intpt[i].pt);
  }
  return true;      
  }
  else
  return false;
  }
  else
  return false;
  }   

  void bodies::Mesh::useDimensions(const shapes::Shape *shape)
  {  
  const shapes::Mesh *mesh = static_cast<const shapes::Mesh*>(shape);
  if (m_btMeshShape)
  delete m_btMeshShape;
  if (m_btMesh)
  delete m_btMesh;
    
  m_btMesh = new btTriangleMesh();
  const unsigned int nt = mesh->triangleCount / 3;
  for (unsigned int i = 0 ; i < nt ; ++i)
  {
  const unsigned int i3 = i *3;
  const unsigned int v1 = 3 * mesh->triangles[i3];
  const unsigned int v2 = 3 * mesh->triangles[i3 + 1];
  const unsigned int v3 = 3 * mesh->triangles[i3 + 2];
  m_btMesh->addTriangle(btVector3(mesh->vertices[v1], mesh->vertices[v1 + 1], mesh->vertices[v1 + 2]),
  btVector3(mesh->vertices[v2], mesh->vertices[v2 + 1], mesh->vertices[v2 + 2]),
  btVector3(mesh->vertices[v3], mesh->vertices[v3 + 1], mesh->vertices[v3 + 2]), true);
  }
    
  m_btMeshShape = new btBvhTriangleMeshShape(m_btMesh, true);
  }

  void bodies::Mesh::updateInternalData(void) 
  {
  if (m_btMeshShape)
  {
  m_btMeshShape->setLocalScaling(btVector3(m_scale, m_scale, m_scale));
  m_btMeshShape->setMargin(m_padding);
  }
  m_iPose = m_pose.inverse();
    
  btTransform id;
  id.setIdentity();
  m_btMeshShape->getAabb(id, m_aabbMin, m_aabbMax);

  btVector3 d = (m_aabbMax - m_aabbMin) / 2.0;

  m_center = m_pose.getOrigin() + d;
  m_radiusBSqr = d.length2();
  m_radiusB = sqrt(m_radiusBSqr);
    
  }

  double bodies::Mesh::computeVolume(void) const
  {
  if (m_btMeshShape)
  {
  // approximation; volume of AABB at identity transform
  btVector3 d = m_aabbMax - m_aabbMin;
  return d.x() * d.y() * d.z();
  }
  else
  return 0.0;
  }

  void bodies::Mesh::computeBoundingSphere(BoundingSphere &sphere) const
  {
  sphere.center = m_center;
  sphere.radius = m_radiusB;
  }

*/

bool bodies::ConvexMesh::containsPoint(const btVector3 &p, bool verbose) const
{
  if (m_boundingBox.containsPoint(p))
  {
    btVector3 ip(m_iPose * p);
    ip = m_meshCenter + (ip - m_meshCenter) * m_scale;
    return isPointInsidePlanes(ip);
  }
  else
    return false;
}

void bodies::ConvexMesh::useDimensions(const shapes::Shape *shape)
{  
  const shapes::Mesh *mesh = static_cast<const shapes::Mesh*>(shape);

  double maxX = -INFINITY, maxY = -INFINITY, maxZ = -INFINITY;
  double minX =  INFINITY, minY =  INFINITY, minZ  = INFINITY;
    
  for(unsigned int i = 0; i < mesh->vertexCount ; ++i)
  {
    double vx = mesh->vertices[3 * i    ];
    double vy = mesh->vertices[3 * i + 1];
    double vz = mesh->vertices[3 * i + 2];
        
    if (maxX < vx) maxX = vx;
    if (maxY < vy) maxY = vy;
    if (maxZ < vz) maxZ = vz;
        
    if (minX > vx) minX = vx;
    if (minY > vy) minY = vy;
    if (minZ > vz) minZ = vz;
  }
    
  if (maxX < minX) maxX = minX = 0.0;
  if (maxY < minY) maxY = minY = 0.0;
  if (maxZ < minZ) maxZ = minZ = 0.0;
    
  shapes::Box *box_shape = new shapes::Box(maxX - minX, maxY - minY, maxZ - minZ);
  m_boundingBox.setDimensions(box_shape);
  delete box_shape;
 
  m_boxOffset.setValue((minX + maxX) / 2.0, (minY + maxY) / 2.0, (minZ + maxZ) / 2.0);
    
  m_planes.clear();
  m_triangles.clear();
  m_vertices.clear();
  m_meshRadiusB = 0.0;
  m_meshCenter.setValue(btScalar(0), btScalar(0), btScalar(0));

  double xdim = maxX - minX;
  double ydim = maxY - minY;
  double zdim = maxZ - minZ;
    
  double pose1;
  double pose2;
    
  unsigned int off1;
  unsigned int off2;
    
  double cyl_length;
  double maxdist = -INFINITY;
    
  if(xdim > ydim && xdim > zdim) {
      
    off1 = 1;
    off2 = 2;
    pose1 = m_boxOffset.y();
    pose2 = m_boxOffset.z();
    cyl_length = xdim;
  } else if(ydim > zdim) {
    off1 = 0;
    off2 = 2;
    pose1 = m_boxOffset.x();
    pose2 = m_boxOffset.z();
    cyl_length = ydim;
  } else {
    off1 = 0;
    off2 = 1;
    pose1 = m_boxOffset.x();
    pose2 = m_boxOffset.y();
    cyl_length = zdim;
  }


  btVector3 *vertices = new btVector3[mesh->vertexCount];
  for(unsigned int i = 0; i < mesh->vertexCount ; ++i)
  {
    vertices[i].setX(mesh->vertices[3 * i    ]);
    vertices[i].setY(mesh->vertices[3 * i + 1]);
    vertices[i].setZ(mesh->vertices[3 * i + 2]);
      
    double dista = mesh->vertices[3 * i + off1]-pose1;
    double distb = mesh->vertices[3 * i + off2]-pose2;
    double dist = sqrt(((dista*dista)+(distb*distb)));
    if(dist > maxdist) {
      maxdist = dist;
    }
  }
  m_boundingCylinder.radius = maxdist;
  m_boundingCylinder.length = cyl_length;
    
  HullDesc hd(QF_TRIANGLES, mesh->vertexCount, vertices);
  HullResult hr;
  HullLibrary hl;
  if (hl.CreateConvexHull(hd, hr) == QE_OK)
  {
    //  std::cout << "Convex hull has " << hr.m_OutputVertices.size() << " vertices (down from " << mesh->vertexCount << "), " << hr.mNumFaces << " faces" << std::endl;

    m_vertices.reserve(hr.m_OutputVertices.size());
    btVector3 sum(0, 0, 0);     
        
    for (int j = 0 ; j < hr.m_OutputVertices.size() ; ++j)
    {
      m_vertices.push_back(hr.m_OutputVertices[j]);
      sum = sum + hr.m_OutputVertices[j];
    }
        
    m_meshCenter = sum / (double)(hr.m_OutputVertices.size());
    for (unsigned int j = 0 ; j < m_vertices.size() ; ++j)
    {
      double dist = m_vertices[j].distance2(m_meshCenter);
      if (dist > m_meshRadiusB)
        m_meshRadiusB = dist;
    }

    m_meshRadiusB = sqrt(m_meshRadiusB);
    m_triangles.reserve(hr.m_Indices.size());
    for (unsigned int j = 0 ; j < hr.mNumFaces ; ++j)
    {
      const btVector3 &p1 = hr.m_OutputVertices[hr.m_Indices[j * 3    ]];
      const btVector3 &p2 = hr.m_OutputVertices[hr.m_Indices[j * 3 + 1]];
      const btVector3 &p3 = hr.m_OutputVertices[hr.m_Indices[j * 3 + 2]];
            
      btVector3 edge1 = (p2 - p1);
      btVector3 edge2 = (p3 - p1);
            
      edge1.normalize();
      edge2.normalize();

      btVector3 planeNormal = edge1.cross(edge2);
            
      if (planeNormal.length2() > btScalar(1e-6))
      {
        planeNormal.normalize();
        btVector4 planeEquation(planeNormal.getX(), planeNormal.getY(), planeNormal.getZ(), -planeNormal.dot(p1));

        unsigned int behindPlane = countVerticesBehindPlane(planeEquation);
        if (behindPlane > 0)
        {
          btVector4 planeEquation2(-planeEquation.getX(), -planeEquation.getY(), -planeEquation.getZ(), -planeEquation.getW());
          unsigned int behindPlane2 = countVerticesBehindPlane(planeEquation2);
          if (behindPlane2 < behindPlane)
          {
            planeEquation.setValue(planeEquation2.getX(), planeEquation2.getY(), planeEquation2.getZ(), planeEquation2.getW());
            behindPlane = behindPlane2;
          }
        }
                
        if (behindPlane > 0)
          ROS_DEBUG("Approximate plane: %d of %d points are behind the plane", behindPlane, (int)m_vertices.size());
                
        m_planes.push_back(planeEquation);

        m_triangles.push_back(hr.m_Indices[j * 3 + 0]);
        m_triangles.push_back(hr.m_Indices[j * 3 + 1]);
        m_triangles.push_back(hr.m_Indices[j * 3 + 2]);
      }
    }
  }
  else
    ROS_ERROR("Unable to compute convex hull.");
    
  hl.ReleaseResult(hr);    
  delete[] vertices;
    
}

void bodies::ConvexMesh::updateInternalData(void) 
{
  btTransform pose = m_pose;
  pose.setOrigin(m_pose * m_boxOffset);
  m_boundingBox.setPose(pose);
  m_boundingBox.setPadding(m_padding);
  m_boundingBox.setScale(m_scale);

  m_iPose = m_pose.inverse();
  m_center = m_pose * m_meshCenter;
  m_radiusB = m_meshRadiusB * m_scale + m_padding;
  m_radiusBSqr = m_radiusB * m_radiusB;

  m_scaledVertices.resize(m_vertices.size());
  for (unsigned int i = 0 ; i < m_vertices.size() ; ++i)
  {
    btVector3 v(m_vertices[i] - m_meshCenter);
    btScalar l = v.length();
    m_scaledVertices[i] = m_meshCenter + v * (m_scale + (l > ZERO ? m_padding / l : 0.0));
  }
}

void bodies::ConvexMesh::computeBoundingSphere(BoundingSphere &sphere) const
{
  sphere.center = m_center;
  sphere.radius = m_radiusB;
}

void bodies::ConvexMesh::computeBoundingCylinder(BoundingCylinder &cylinder) const
{
  cylinder.length = m_boundingCylinder.length;
  cylinder.radius = m_boundingCylinder.radius;
  //need to do rotation correctly to get pose, which bounding box does
  BoundingCylinder cyl;
  m_boundingBox.computeBoundingCylinder(cyl);
  cylinder.pose = cyl.pose;
}

bool bodies::ConvexMesh::isPointInsidePlanes(const btVector3& point) const
{
  unsigned int numplanes = m_planes.size();
  for (unsigned int i = 0 ; i < numplanes ; ++i)
  {
    const btVector4& plane = m_planes[i];
    btScalar dist = plane.dot(point) + plane.getW() - m_padding - btScalar(1e-6);
    if (dist > btScalar(0))
      return false;
  }
  return true;
}

unsigned int bodies::ConvexMesh::countVerticesBehindPlane(const btVector4& planeNormal) const
{
  unsigned int numvertices = m_vertices.size();
  unsigned int result = 0;
  for (unsigned int i = 0 ; i < numvertices ; ++i)
  {
    btScalar dist = planeNormal.dot(m_vertices[i]) + planeNormal.getW() - btScalar(1e-6);
    if (dist > btScalar(0))
      result++;
  }
  return result;
}

double bodies::ConvexMesh::computeVolume(void) const
{
  double volume = 0.0;
  for (unsigned int i = 0 ; i < m_triangles.size() / 3 ; ++i)
  {
    const btVector3 &v1 = m_vertices[m_triangles[3*i + 0]];
    const btVector3 &v2 = m_vertices[m_triangles[3*i + 1]];
    const btVector3 &v3 = m_vertices[m_triangles[3*i + 2]];
    volume += v1.x()*v2.y()*v3.z() + v2.x()*v3.y()*v1.z() + v3.x()*v1.y()*v2.z() - v1.x()*v3.y()*v2.z() - v2.x()*v1.y()*v3.z() - v3.x()*v2.y()*v1.z();
  }
  return fabs(volume)/6.0;
}

bool bodies::ConvexMesh::intersectsRay(const btVector3& origin, const btVector3& dir, std::vector<btVector3> *intersections, unsigned int count) const
{
  if (distanceSQR(m_center, origin, dir) > m_radiusBSqr) return false;
  if (!m_boundingBox.intersectsRay(origin, dir)) return false;
    
  // transform the ray into the coordinate frame of the mesh
  btVector3 orig(m_iPose * origin);
  btVector3 dr(m_iPose.getBasis() * dir);
    
  std::vector<detail::intersc> ipts;
    
  bool result = false;
    
  // for each triangle 
  const unsigned int nt = m_triangles.size() / 3;
  for (unsigned int i = 0 ; i < nt ; ++i)
  {
    btScalar tmp = m_planes[i].dot(dr);
    if (fabs(tmp) > ZERO)
    {
      double t = -(m_planes[i].dot(orig) + m_planes[i].getW()) / tmp;
      if (t > 0.0)
      {
        const int i3 = 3 * i;
        const int v1 = m_triangles[i3 + 0];
        const int v2 = m_triangles[i3 + 1];
        const int v3 = m_triangles[i3 + 2];
                
        const btVector3 &a = m_scaledVertices[v1];
        const btVector3 &b = m_scaledVertices[v2];
        const btVector3 &c = m_scaledVertices[v3];
                
        btVector3 cb(c - b);
        btVector3 ab(a - b);
                
        // intersection of the plane defined by the triangle and the ray
        btVector3 P(orig + dr * t);
                
        // check if it is inside the triangle
        btVector3 pb(P - b);
        btVector3 c1(cb.cross(pb));
        btVector3 c2(cb.cross(ab));
        if (c1.dot(c2) < 0.0)
          continue;
                
        btVector3 ca(c - a);
        btVector3 pa(P - a);
        btVector3 ba(-ab);
                
        c1 = ca.cross(pa);
        c2 = ca.cross(ba);
        if (c1.dot(c2) < 0.0)
          continue;
                
        c1 = ba.cross(pa);
        c2 = ba.cross(ca);
                
        if (c1.dot(c2) < 0.0)
          continue;
                
        result = true;
        if (intersections)
        {
          detail::intersc ip(origin + dir * t, t);
          ipts.push_back(ip);
        }
        else
          break;
      }
    }
  }

  if (intersections)
  {
    std::sort(ipts.begin(), ipts.end(), detail::interscOrder());
    const unsigned int n = count > 0 ? std::min<unsigned int>(count, ipts.size()) : ipts.size();
    for (unsigned int i = 0 ; i < n ; ++i)
      intersections->push_back(ipts[i].pt);
  }
    
  return result;
}

bodies::BodyVector::BodyVector(){
}

bodies::BodyVector::BodyVector(const std::vector<shapes::Shape*>& shapes, 
                               const std::vector<btTransform>& poses,
                               double padding)
{
  padding_ = padding;
  for(unsigned int i = 0; i < shapes.size(); i++) {
    addBody(shapes[i],poses[i], padding_);
  }
}


bodies::BodyVector::~BodyVector() {
  for(unsigned int i = 0; i < bodies_.size(); i++) {
    delete bodies_[i];
  }
  for(unsigned int i = 0; i < padded_bodies_.size(); i++) {
    delete padded_bodies_[i];
  }
}

void bodies::BodyVector::addBody(const shapes::Shape* shape, const btTransform& pose, double padding) {
  bodies::Body* body = bodies::createBodyFromShape(shape);
  body->setPose(pose);
  bodies_.push_back(body);
  BoundingSphere sphere;
  body->computeBoundingSphere(sphere);
  rsqrs_.push_back(sphere.radius*sphere.radius);
  if(padding > 0.0) {
    bodies::Body* padded_body = bodies::createBodyFromShape(shape);
    padded_body->setPose(pose);
    padded_body->setPadding(padding);
    padded_bodies_.push_back(padded_body);
    BoundingSphere padded_sphere;
    padded_body->computeBoundingSphere(padded_sphere);
    padded_rsqrs_.push_back(padded_sphere.radius*padded_sphere.radius);
  }
}

void bodies::BodyVector::setPose(unsigned int i, const btTransform& pose)
{
  if(i >= bodies_.size()) return;
  bodies_[i]->setPose(pose);
  if(padding_ > 0.0) {
    padded_bodies_[i]->setPose(pose);
  }
}

const bodies::Body* bodies::BodyVector::getBody(unsigned int i) const
{
  if(i >= bodies_.size()) return NULL;
  return bodies_[i];
}

const bodies::Body* bodies::BodyVector::getPaddedBody(unsigned int i) const
{
  if(i >= bodies_.size()) return NULL;
  if(padding_ > 0.0) {
    return padded_bodies_[i];
  } 
  return bodies_[i];
}


bodies::BoundingSphere bodies::BodyVector::getBoundingSphere(unsigned int i) const
{
  if(i >= bodies_.size()) {
    ROS_WARN("Trying to get sphere for body we don't have.  Probably segfault");
  }
  BoundingSphere sphere;
  bodies_[i]->computeBoundingSphere(sphere);
  return sphere;
}

bodies::BoundingSphere bodies::BodyVector::getPaddedBoundingSphere(unsigned int i) const
{
  if(i >= bodies_.size()) {
    ROS_WARN("Trying to get sphere for body we don't have.  Probably segfault");
  }
  BoundingSphere sphere;
  if(padding_ > 0.0) {
    padded_bodies_[i]->computeBoundingSphere(sphere);
  } else {
    bodies_[i]->computeBoundingSphere(sphere);
  }
  return sphere;
}

double bodies::BodyVector::getBoundingSphereRadiusSquared(unsigned int i) const
{
  if(i >= rsqrs_.size()) {
    return -1.0;
  }
  return rsqrs_[i];
}

double bodies::BodyVector::getPaddedBoundingSphereRadiusSquared(unsigned int i) const
{
  if(i >= rsqrs_.size()) {
    return -1.0;
  }
  if(padding_ > 0.0) {
    return padded_rsqrs_[i];
  } 
  return rsqrs_[i];
}

---

geometric_shapes
Author(s): Ioan Sucan
autogenerated on Fri Mar 1 14:16:09 2013