cellgrid.cpp

/***************************************************************************
 *   Copyright (C) 2005-2008 by the FIFE team                              *
 *   http://www.fifengine.de                                               *
 *   This file is part of FIFE.                                            *
 *                                                                         *
 *   FIFE is free software; you can redistribute it and/or                 *
 *   modify it under the terms of the GNU Lesser General Public            *
 *   License as published by the Free Software Foundation; either          *
 *   version 2.1 of the License, or (at your option) any later version.    *
 *                                                                         *
 *   This library is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 *   Lesser General Public License for more details.                       *
 *                                                                         *
 *   You should have received a copy of the GNU Lesser General Public      *
 *   License along with this library; if not, write to the                 *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
 ***************************************************************************/

// Standard C++ library includes
#include <cassert>

// 3rd party library includes

// FIFE includes
// These includes are split up in two parts, separated by one empty line
// First block: files included from the FIFE root src directory
// Second block: files included from the same folder
#include "util/log/logger.h"

#include "cellgrid.h"

namespace FIFE {
    static Logger _log(LM_CELLGRID);

    CellGrid::CellGrid(bool allow_diagonals):
        FifeClass(),
        m_matrix(),
        m_inverse_matrix(),
        m_xshift(0),
        m_yshift(0),
        m_zshift(0),
        m_xscale(1),
        m_yscale(1),
        m_rotation(0),
        m_allow_diagonals(allow_diagonals) {
        updateMatrices();
    }

    CellGrid::~CellGrid() {
    }

    void CellGrid::getAccessibleCoordinates(const ModelCoordinate& curpos, std::vector<ModelCoordinate>& coordinates) {
        coordinates.clear();
        for (int32_t x = curpos.x - 1; x <= curpos.x + 1; x++) {
            for (int32_t y = curpos.y - 1; y <= curpos.y + 1; y++) {
                ModelCoordinate pt;
                pt.x = x;
                pt.y = y;
                if (isAccessible(curpos, pt)) {
                    coordinates.push_back(pt);
                }
            }
        }
    }

    void CellGrid::updateMatrices() {
        m_matrix.loadRotate(m_rotation, 0.0, 0.0, 1.0);
        m_matrix.applyScale(m_xscale,m_yscale, 1);
        m_matrix.applyTranslate(m_xshift, m_yshift, m_zshift);
        m_inverse_matrix = m_matrix.inverse();
    }

    ExactModelCoordinate CellGrid::toMapCoordinates(const ModelCoordinate& layer_coords) {
        return toMapCoordinates(intPt2doublePt(layer_coords));
    }

    int32_t CellGrid::orientation(const ExactModelCoordinate& pt, const ExactModelCoordinate& pt1, const ExactModelCoordinate& pt2) {
        double o = (pt2.x - pt1.x) * (pt.y - pt1.y) - (pt.x - pt1.x) * (pt2.y - pt1.y);
        if (o > 0.0) {
            return 1;
        } else if (o < 0.0) {
            return -1;
        }
        return 0;
    }
    
    bool CellGrid::ptInTriangle(const ExactModelCoordinate& pt, const ExactModelCoordinate& pt1, const ExactModelCoordinate& pt2, const ExactModelCoordinate& pt3) {
        double o1 = orientation(pt1, pt2, pt);
        double o2 = orientation(pt2, pt3, pt);
        double o3 = orientation(pt3, pt1, pt);
        bool result = (o1 == o2) && (o2 == o3);
        FL_DBG(_log, LMsg("ptInTriangle, pt=") << pt << " pt1=" << pt1 << " pt2=" << pt2 << " pt3=" << pt3 << " in=" << result);
        return result;
    }
}