dijkstra.h

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#ifndef _DIJKSTRA_H
#define _DIJKSTRA_H
 
#define PRIORITYBUFSIZE 10000
#include <math.h>
#include <stdint.h>
#include <string.h>
#include <stdio.h>
 
#include <global_planner/planner_core.h>
#include <global_planner/expander.h>
 
// inserting onto the priority blocks
#define push_cur(n)  { if (n>=0 && n<ns_ && !pending_[n] && getCost(costs, n)<lethal_cost_ && currentEnd_<PRIORITYBUFSIZE){ currentBuffer_[currentEnd_++]=n; pending_[n]=true; }}
#define push_next(n) { if (n>=0 && n<ns_ && !pending_[n] && getCost(costs, n)<lethal_cost_ &&    nextEnd_<PRIORITYBUFSIZE){    nextBuffer_[   nextEnd_++]=n; pending_[n]=true; }}
#define push_over(n) { if (n>=0 && n<ns_ && !pending_[n] && getCost(costs, n)<lethal_cost_ &&    overEnd_<PRIORITYBUFSIZE){    overBuffer_[   overEnd_++]=n; pending_[n]=true; }}
 
namespace global_planner {
class DijkstraExpansion : public Expander {
    public:
        DijkstraExpansion(PotentialCalculator* p_calc, int nx, int ny);
        virtual ~DijkstraExpansion();
        bool calculatePotentials(unsigned char* costs, double start_x, double start_y, double end_x, double end_y, int cycles,
                                float* potential);
 
        void setSize(int nx, int ny); 
        void setNeutralCost(unsigned char neutral_cost) {
            neutral_cost_ = neutral_cost;
            priorityIncrement_ = 2 * neutral_cost_;
        }
 
        void setPreciseStart(bool precise){ precise_ = precise; }
    private:
 
        void updateCell(unsigned char* costs, float* potential, int n); 
        float getCost(unsigned char* costs, int n) {
            float c = costs[n];
            if (c < lethal_cost_ - 1 || (unknown_ && c==255)) {
                c = c * factor_ + neutral_cost_;
                if (c >= lethal_cost_)
                    c = lethal_cost_ - 1;
                return c;
            }
            return lethal_cost_;
        }
 
        int *buffer1_, *buffer2_, *buffer3_; 
        int *currentBuffer_, *nextBuffer_, *overBuffer_; 
        int currentEnd_, nextEnd_, overEnd_; 
        bool *pending_; 
        bool precise_;
 
        float threshold_; 
        float priorityIncrement_; 
};
} //end namespace global_planner
#endif