kicad/include/geometry/shape.h

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2013 CERN
 * @author Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
 *
 * This program 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, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#ifndef __SHAPE_H
#define __SHAPE_H

#include <math/vector2d.h>
#include <math/box2.h>

#include <geometry/seg.h>

/**
 * Enum ShapeType
 * Lists all supported shapes
 */

enum ShapeType {
	SH_RECT = 0, 	///> axis-aligned rectangle
	SH_SEGMENT,		///> line segment
	SH_LINE_CHAIN,	///> line chain (polyline)
	SH_CIRCLE		///> circle
};

/**
 * Class SHAPE
 * 
 * Represents an abstract shape on 2D plane. All SHAPEs implement SHAPE interface.
 */	
class SHAPE {
	protected:
		typedef VECTOR2I::extended_type ecoord;

	public:
		/**
		 * Constructor
		 *
		 * Creates an empty shape of type aType
		 */

		SHAPE ( ShapeType aType ): m_type( aType ) { };
		
		// Destructor
		virtual ~SHAPE() {};

		/**
		 * Function Type()
		 *
		 * Returns the type of the shape.
		 * @retval the type
		 */
		ShapeType Type() const { return m_type; }

		/**
		 * Function Clone()
		 *
		 * Returns a dynamically allocated copy of the shape
		 * @retval copy of the shape
		 */
		virtual SHAPE* Clone() const { 
			assert(false); 
			return NULL; 
		};

		/**
		 * Function Collide()
		 *
		 * Checks if the boundary of shape (this) lies closer to the point aP than aClearance, indicating
		 * a collision.
		 * @return true, if there is a collision.
		 */
		virtual bool Collide ( const VECTOR2I& aP, int aClearance = 0 ) const
		{
			return Collide(SEG(aP, aP), aClearance);
		}
		
		/**
		 * Function Collide()
		 *
		 * Checks if the boundary of shape (this) lies closer to the shape aShape than aClearance, indicating
		 * a collision.
		 * @return true, if there is a collision.
		 */
		virtual bool Collide ( const SHAPE *aShape, int aClerance, VECTOR2I& aMTV ) const;
		virtual bool Collide ( const SHAPE *aShape, int aClerance = 0 ) const;
		/**
		 * Function Collide()
		 *
		 * Checks if the boundary of shape (this) lies closer to the segment aSeg than aClearance, indicating
		 * a collision.
		 * @return true, if there is a collision.
		 */
		virtual bool Collide ( const SEG& aSeg, int aClearance = 0) const = 0;
	
		/**
		 * Function Collide()
		 *
		 * Computes a bounding box of the shape, with a margin of aClearance
		 * a collision.
		 * @aClearance how much the bounding box is expanded wrs to the minimum enclosing rectangle for the shape.
		 * @return the bounding box.
		 */
		virtual const BOX2I BBox ( int aClearance = 0 ) const = 0;

		/**
		 * Function Centre()
		 *
		 * Computes a center-of-mass of the shape
		 * @return the center-of-mass point
		 */
		virtual VECTOR2I Centre() const
		{
			return BBox(0).Centre(); // if nothing better is available....
		}

	private:
		///> type of our shape
		ShapeType m_type;

};

bool CollideShapes ( const SHAPE *a, const SHAPE *b, int clearance, bool needMTV, VECTOR2I& aMTV );

#endif // __SHAPE_H