OpenSpace/modules/autonavigation/pathcurves.h

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 * OpenSpace                                                                             *
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#ifndef __OPENSPACE_MODULE_AUTONAVIGATION___PATHCURVE___H__
#define __OPENSPACE_MODULE_AUTONAVIGATION___PATHCURVE___H__

#include <modules/autonavigation/camerastate.h>
#include <ghoul/glm.h>
#include <vector>

namespace openspace::autonavigation {

// OBS! Path curves has curve parameter in range [0,1]
class PathCurve {
public:
    virtual ~PathCurve() = 0;

    const double length() const;
    double arcLength(double limit = 1.0);

    // comppute the value at the relative length s [0,1]
    virtual glm::dvec3 positionAt(double u) = 0;

    std::vector<glm::dvec3> getPoints(); // for debugging

protected:
    // the points used for creating the curve (e.g. control points of a Bezier curve)
    std::vector<glm::dvec3> _points; 

    // the total length of the curve (approximated)
    double _length;
};

class Bezier3Curve : public PathCurve {
public:
    Bezier3Curve(CameraState& start, CameraState& end);
    glm::dvec3 positionAt(double u);

private:
    void initParameterIntervals();

    std::vector<double> _parameterIntervals;
    unsigned int _nrSegments;
};

class LinearCurve : public PathCurve {
public:
    LinearCurve(CameraState& start, CameraState& end);
    glm::dvec3 positionAt(double u);

};

// OBS! This is a temporary class specialised for handling pauses. 
// TODO: handle better in the future. 
class PauseCurve : public PathCurve {
public:
    PauseCurve(CameraState& state);
    glm::dvec3 positionAt(double u);
};

} // namespace openspace::autonavigation

#endif // __OPENSPACE_MODULE_AUTONAVIGATION___PATHCURVE___H__