#ifndef RASTER_EDGE_EVALUATOR_HPP
#define RASTER_EDGE_EVALUATOR_HPP
#include "raster_edge_evaluator.h"
//*******************************************************************************
// Raster Edge Evaluator implementation
//*******************************************************************************
template <typename RanIt>
RasterEdgeEvaluator<RanIt>::RasterEdgeEvaluator(
const iterator_type &begin, const iterator_type &end,
double tolerance, double maxLength)
: tcg::polyline_ops::StandardDeviationEvaluator<RanIt>(begin, end), m_tolerance(tolerance), m_maxLength(maxLength)
{
}
//--------------------------------------------------------------------------
template <typename RanIt>
typename RasterEdgeEvaluator<RanIt>::penalty_type
RasterEdgeEvaluator<RanIt>::penalty(const iterator_type &a, const iterator_type &b)
{
return tcg::point_ops::norm(*b - *a) * tcg::polyline_ops::StandardDeviationEvaluator<RanIt>::penalty(a, b);
}
//--------------------------------------------------------------------------
template <typename RanIt>
typename RasterEdgeEvaluator<RanIt>::iterator_type
RasterEdgeEvaluator<RanIt>::furthestFrom(const iterator_type &start)
{
//Build the furthest possible forward difference for every vertex between begin and end.
point_type displace, oldDisplace;
point_type leftConstraint, rightConstraint;
point_type newLeftConstraint, newRightConstraint;
point_type leftDirConstr, rightDirConstr, dir, oldDir;
iterator_type it = start, jt;
const double sqMaxLength = sq(m_maxLength);
//Initialize search
leftConstraint = rightConstraint = point_type();
leftDirConstr = rightDirConstr = point_type();
oldDir = oldDisplace = point_type();
if (it != this->m_begin)
--it; //Chop left
jt = it;
for (++jt; jt != this->m_end; ++jt) {
//Retrieve displacement from *it
displace = point_type(jt->x - it->x, jt->y - it->y);
dir = point_type(displace.x - oldDisplace.x, displace.y - oldDisplace.y);
//Max length
if (oldDir.x != 0 || oldDir.y != 0) {
if (sq(displace.x) + sq(displace.y) > sqMaxLength)
break;
} else
leftDirConstr = rightDirConstr = dir;
//Test displacement against the oldDisplacement. If it's reversing the
//direction, make it invalid.
if (cross(oldDir, dir) > 0)
leftDirConstr = dir;
if (cross(oldDir, dir) < 0)
rightDirConstr = dir;
//Test constraints
/*if(cross(rightDirConstr, leftDirConstr) <= 0 &&
leftDirConstr * rightDirConstr < 0)
break;*/
if (cross(rightDirConstr, leftDirConstr) < 0)
break;
if (cross(displace, leftConstraint) < 0)
break;
if (cross(displace, rightConstraint) > 0)
break;
if (tmax(displace.x, -displace.x, displace.y, -displace.y) > m_tolerance) {
//Update m_tolerance constraints
newLeftConstraint.x = displace.x +
(displace.y < 0 || (displace.y == 0 && displace.x < 0) ? m_tolerance : -m_tolerance);
newLeftConstraint.y = displace.y +
(displace.x > 0 || (displace.x == 0 && displace.y < 0) ? m_tolerance : -m_tolerance);
if (cross(newLeftConstraint, leftConstraint) >= 0)
leftConstraint = newLeftConstraint;
newRightConstraint.x = displace.x +
(displace.y > 0 || (displace.y == 0 && displace.x < 0) ? m_tolerance : -m_tolerance);
newRightConstraint.y = displace.y +
(displace.x < 0 || (displace.x == 0 && displace.y < 0) ? m_tolerance : -m_tolerance);
if (cross(newRightConstraint, rightConstraint) <= 0)
rightConstraint = newRightConstraint;
}
oldDisplace = displace;
oldDir = dir;
}
if (jt != this->m_end)
--jt; //Chop Right
return start + tmax((int)tmin(jt - start - 1, this->m_end - this->m_begin - 2), 1);
}
#endif // RASTER_EDGE_EVALUATOR_HPP