--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/engine/core/model/metamodel/grids/squaregrid.cpp	Sun Jun 29 18:44:17 2008 +0000
@@ -0,0 +1,135 @@
+/***************************************************************************
+ *   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 General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program 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 General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA              *
+ ***************************************************************************/
+
+// Standard C++ library includes
+#include <cassert>
+#include <iostream>
+
+// 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/math/fife_math.h"
+#include "util/log/logger.h"
+
+#include "squaregrid.h"
+
+namespace FIFE {
+	static Logger _log(LM_SQUAREGRID);
+
+	SquareGrid::SquareGrid(bool allow_diagonals): 
+		CellGrid(allow_diagonals) {
+	}
+
+	SquareGrid::~SquareGrid() {
+	}
+
+	bool SquareGrid::isAccessible(const ModelCoordinate& curpos, const ModelCoordinate& target) {
+		if (curpos == target)
+			return true;
+		if ((curpos.x == target.x) && (curpos.y - 1 == target.y))
+			return true;
+		if ((curpos.x == target.x) && (curpos.y + 1 == target.y))
+			return true;
+		if ((curpos.x + 1 == target.x) && (curpos.y == target.y))
+			return true;
+		if ((curpos.x - 1 == target.x) && (curpos.y == target.y))
+			return true;
+
+		if (m_allow_diagonals) {
+			return isAccessibleDiagonal(curpos, target);
+		}
+
+		return false;
+	}
+
+	bool SquareGrid::isAccessibleDiagonal(const ModelCoordinate& curpos, const ModelCoordinate& target) {
+		if ((curpos.x - 1 == target.x) && (curpos.y - 1 == target.y))
+			return true;
+		if ((curpos.x - 1 == target.x) && (curpos.y + 1 == target.y))
+			return true;
+		if ((curpos.x + 1 == target.x) && (curpos.y - 1 == target.y))
+			return true;
+		if ((curpos.x + 1 == target.x) && (curpos.y + 1 == target.y))
+			return true;
+		return false;
+	}
+
+	float SquareGrid::getAdjacentCost(const ModelCoordinate& curpos, const ModelCoordinate& target) {
+		assert(isAccessible(curpos, target));
+		if (curpos == target) {
+			return 0;
+		}
+		if (isAccessibleDiagonal(curpos, target)) {
+			return sqrt(m_xscale*m_xscale + m_yscale*m_yscale);
+		}
+		if (curpos.x == target.x) {
+			return m_xscale;
+		}
+		return m_yscale;
+	}
+
+	const std::string& SquareGrid::getType() const {
+		static std::string type("square");
+		return type;
+	}
+
+	const std::string& SquareGrid::getName() const {
+		static std::string squareGrid("Square Grid");
+		return squareGrid;
+	}
+
+	ExactModelCoordinate SquareGrid::toMapCoordinates(const ExactModelCoordinate& layer_coords) {
+		return m_matrix * layer_coords;
+	}
+
+	ExactModelCoordinate SquareGrid::toExactLayerCoordinates(const ExactModelCoordinate& map_coord) {
+		return m_inverse_matrix * map_coord;
+	}
+
+	ModelCoordinate SquareGrid::toLayerCoordinates(const ExactModelCoordinate& map_coord) {
+		ExactModelCoordinate dblpt = toExactLayerCoordinates(map_coord);
+		ModelCoordinate result;
+		result.x = static_cast<int>(floor(dblpt.x));
+		result.y = static_cast<int>(floor(dblpt.y));
+		
+		if ((dblpt.x - static_cast<double>(result.x)) > 0.5) {
+			result.x++;
+		}
+		if ((dblpt.y - static_cast<double>(result.y)) > 0.5) {
+			result.y++;
+		}
+		
+		return result;
+	}
+	
+	void SquareGrid::getVertices(std::vector<ExactModelCoordinate>& vtx, const ModelCoordinate& cell) {
+		vtx.clear();
+		double x = static_cast<double>(cell.x);
+		double y = static_cast<double>(cell.y);
+		vtx.push_back(ExactModelCoordinate(x-0.5, y-0.5));
+		vtx.push_back(ExactModelCoordinate(x+0.5, y-0.5));
+		vtx.push_back(ExactModelCoordinate(x+0.5, y+0.5));
+		vtx.push_back(ExactModelCoordinate(x-0.5, y+0.5));
+	}
+}