kicad/include/transform.h

/**
 * @file transform.h
 */

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2007-2010 Wayne Stambaugh <stambaughw@gmail.com>
 * Copyright (C) 2007-2021 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * 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 _TRANSFORM_H_
#define _TRANSFORM_H_

#include <geometry/eda_angle.h>
#include <math/box2.h>


/**
 * for transforming drawing coordinates for a wxDC device context.
 *
 * This probably should be a base class with all pure virtual methods and a WXDC_TRANSFORM
 * derived class.  Then in the future if some new device context is used, a new transform could
 * be derived from the base class and all the drawable objects would have to do is provide
 * overloaded draw methods to use the new transform.
 */
class TRANSFORM
{
public:
    int x1;
    int y1;
    int x2;
    int y2;

    /**
     * The default construct creates a transform that draws object is the normal orientation.
     */
    TRANSFORM() : x1( 1 ), y1( 0 ), x2( 0 ), y2( -1 ) {}

    TRANSFORM( int ax1, int ay1, int ax2, int ay2 ) : x1( ax1 ), y1( ay1 ), x2( ax2 ), y2( ay2 ) {}

    bool operator==( const TRANSFORM& aTransform ) const;

    bool operator!=( const TRANSFORM& aTransform ) const { return !( *this == aTransform ); }

   /**
    * Calculate a new coordinate according to the mirror/rotation transform.
    * Useful to calculate actual coordinates of a point from coordinates relative to a symbol,
    * which are given for a non-rotated,-non mirrored item.
    * @param aPoint = The position to transform
    * @return The transformed coordinate.
    */
    VECTOR2I TransformCoordinate( const VECTOR2I& aPoint ) const;

   /**
    * Calculate a new rect according to the mirror/rotation transform.
    * Useful to calculate actual coordinates of a point from coordinates relative to a symbol,
    * which are given for a non-rotated,-non mirrored item.
    * @param aRect = The rectangle to transform
    * @return The transformed rectangle.
    */
    BOX2I TransformCoordinate( const BOX2I& aRect ) const;

    /**
    * Calculate the Inverse mirror/rotation transform.
    * Useful to calculate coordinates relative to a symbol, which must be for a non-rotated,
    * non-mirrored item from the actual coordinate.
    * @return The inverse transform.
    */
    TRANSFORM InverseTransform( ) const;

   /**
    * Calculate new angles according to the transform.
    *
    * @param aAngle1 = The first angle to transform
    * @param aAngle2 = The second angle to transform
    * @return True if the angles were swapped during the transform.
    */
   bool MapAngles( EDA_ANGLE* aAngle1, EDA_ANGLE* aAngle2 ) const;
};

namespace std
{
    template <> struct hash<TRANSFORM>
    {
        size_t operator() ( const TRANSFORM& k ) const;
    };
}

#endif    // _TRANSFORM_H_