geom.h

/*== SAGITTARIUS =====================================================================
 * Copyright (c) 2012, Jesse K Medley
 * All rights reserved.

 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    * Neither the name of The University of Washington nor the
      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

//== FILEDOC =========================================================================

//== BEGINNING OF CODE ===============================================================

#ifndef __GRAPHFAB_MATH_GEOM_H_
#define __GRAPHFAB_MATH_GEOM_H_

//== INCLUDES ========================================================================

#include "graphfab/core/SagittariusCore.h"
#include "graphfab/layout/point.h"
#include "graphfab/layout/box.h"
#include "graphfab/math/sign_mag.h"

#include <math.h>

//-- C++ code --
#ifdef __cplusplus

namespace Graphfab {
    
    inline Real deg2r(const Real deg) {
        const Real pi = 3.14159;
        return deg*pi/180.;
    }

    inline Point computeCubic(const Point& alpha, const Point& beta, const Point& gamma, const Point& delta, Real t) {
      return alpha*t*t*t + beta*t*t + gamma*t + delta;
    }
    
    inline Point new2ndPos(const Point& first, const Point& second, const Real deg, const Real dist, const bool rel_dist) {
        Real h, o, a, x;
        Real hnew, onew, anew;
        
        o = second.y - first.y;
        a = second.x - first.x;
        h = sqrt(pow(a,2.) + pow(o,2.));
        
        if(rel_dist)
            hnew = h + h*dist;
        else
            hnew = h + dist;
        
        const Real ep = 1e-6;
        
        if(mag(a) > ep)
            x = atan(o/a);
        else
            x = sign(o)*3.14159/2.;
        
        onew = hnew * sin(x + deg2r(deg));
        anew = hnew * cos(x + deg2r(deg));
        
        if(second.x >= first.x)
            return Point(first.x + anew, first.y + onew);
        else
            return Point(first.x - anew, first.y - onew);
    }
    
    // bounding box-based
    Point calcCurveBackup(const Point& src, const Point& cent, const Box& ext, Real dist = 20);

    class Line2Desc {
    public:
      Line2Desc(const Point& start, const Point& end);

      Real getA() const { return A_; }

      Real getB() const { return B_; }

      Real getC() const { return C_; }

    protected:
      Real A_, B_, C_;

          _GraphfabExport friend std::ostream& operator<<(std::ostream& o, const Line2Desc& c);
    };

    _GraphfabExport std::ostream& operator<<(std::ostream& o, const Line2Desc& c);

    class CubicBezier2Desc {
    public:
      CubicBezier2Desc(const Point& start, const Point& c1, const Point& c2, const Point& end);

      Point p(Real t) const;

      Point getCP(int n) const;

    protected:
      Point P0_, P1_, P2_, P3_;

          _GraphfabExport friend std::ostream& operator<<(std::ostream& o, const CubicBezier2Desc& c);
    };

    _GraphfabExport std::ostream& operator<<(std::ostream& o, const CubicBezier2Desc& c);

    // http://www.particleincell.com/blog/2013/cubic-line-intersection/
    class CubicBezierIntersection {
    public:
      CubicBezierIntersection(const Line2Desc& l, const CubicBezier2Desc& c);

      const std::vector<Real>& getIntersectionPoints() const { return r_; }

    protected:
      std::vector<Real> r_;
    };

//     class LinearIntersectionResults {
//     public:
//       const Point& p() { return p_; }
//       bool exists() { return v_; }
//
//     protected:
//       Point p_;
//       bool v_;
//
//       friend class LinearIntersection;
//     };

    class LinearIntersection {
    public:
      LinearIntersection(const Point& pbegin, const Point& pend, const Point& qbegin, const Point& qend);

      const Point& p() { return p_; }
      bool exists() { return v_; }

    protected:
      Point p_;
      bool v_;
    };
    
}

#else                                                       // __cplusplus



#endif                                                      // __cplusplus

#endif