File indexing completed on 2024-12-08 08:10:33

 /***************************************************************************
  *   Copyright (C) 2004-2005 by David Saxton                               *
  *   david@bluehaze.org                                                    *
  *                                                                         *
  *   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.                                   *
  ***************************************************************************/
 
 #ifndef MECHANICSITEM_H
 #define MECHANICSITEM_H
 
 #include <QList>
 #include <item.h>
 
 class LibraryItem;
 class MechanicsItem;
 // class MechanicsItemOverlayItem;
 class MechanicsDocument;
 typedef QList<MechanicsItem *> MechanicsItemList;
 
 /**
 @short Stores mass, moment of inertia
 @author David Saxton
 */
 class MechanicsInfo
 {
 public:
     MechanicsInfo();
 
     double mass;            // Mass
     double momentOfInertia; // Moment of inertia
 };
 
 class CombinedMechanicsInfo : public MechanicsInfo
 {
 public:
     CombinedMechanicsInfo();
     CombinedMechanicsInfo(const MechanicsInfo &info);
 
     double x; // X coordinate of center of mass
     double y; // Y coordinate of center of mass
 };
 
 /**
 @short Stores a position and orientation
 @author David Saxton
 */
 class PositionInfo
 {
 public:
     PositionInfo();
     /**
      * Adds together two positions: for this=PARENT +(CHILD), the new position
      * is formed by translating this position by that of the CHILDs
      * translation, and then rotating everything about the center of this item
      */
     const PositionInfo operator+(const PositionInfo &info);
     /**
      * Not quite the inverse of operator+. Subtracts the given position info
      * as if it was applied before this current info.
      */
     const PositionInfo operator-(const PositionInfo &info);
     /**
      * x position (0 is left)
      */
     double x() const
     {
         return m_x;
     }
     /**
      * y position (0 is top)
      */
     double y() const
     {
         return m_y;
     }
     /**
      * Angle in radians, positive direction is anticlockwise
      */
     double angle() const
     {
         return m_angle;
     }
     /**
      * Sets the x-position
      */
     void setX(double x)
     {
         m_x = x;
     }
     /**
      * Sets the y-position
      */
     void setY(double y)
     {
         m_y = y;
     }
     /**
      * Sets the angle
      */
     void setAngle(double angle)
     {
         m_angle = angle;
     }
     /**
      * Adds (x,y) to the current position
      */
     void translate(double dx, const double dy)
     {
         m_x += dx;
         m_y += dy;
     }
     /**
      * Rotates anticlockwise by the given amount (in radians)
      */
     void rotate(double angle)
     {
         m_angle += angle;
     }
     /**
      * Resets the position to (0,0), and the orientation to 0
      */
     void reset();
     /**
      * Rotates the current position about the given point through the given
      * angle in radians anticlockwise. This will change the position and
      * orientation.
      */
     void rotateAboutPoint(double x, double y, double angle);
 
 protected:
     double m_x;
     double m_y;
     double m_angle;
 };
 
 /**
 @author David Saxton
 */
 class MechanicsItem : public Item
 {
     Q_OBJECT
 public:
     MechanicsItem(MechanicsDocument *mechanicsDocument, bool newItem, const QString &id);
     ~MechanicsItem() override;
 
     enum SelectionMode { sm_move, sm_resize, sm_rotate };
     /**
      * Sets the selection mode (sm_resize or sm_rotate). Note that setSelected
      * also needs to be called to select the item.
      */
     void setSelectionMode(SelectionMode sm);
     void setSelected(bool yes) override;
     /**
      * @returns the selection mode
      */
     SelectionMode selectionMode() const
     {
         return m_selectionMode;
     }
     /**
      * Move the MechanicsItem by the given amount
      */
     void moveBy(double dx, double dy) override;
     /**
      * Returns the absolute position on the canvas
      */
     PositionInfo absolutePosition() const;
     /**
      * Returns the position relative to the parent item (or the absolute
      * position if there is no parent item)
      */
     PositionInfo relativePosition() const
     {
         return m_relativePosition;
     }
     /**
      * Returns the mechanics info for this item (so not taking into account that
      * of attached children)
      */
     MechanicsInfo *mechanicsInfo()
     {
         return &m_mechanicsInfo;
     }
     /**
      * Returns the combined mechanics info for this item (which takes into
      * account that of attached children).
      */
     CombinedMechanicsInfo *mechanicsInfoCombined()
     {
         return &m_mechanicsInfoCombined;
     }
     /**
      * Returns the rectangle that can legitimately fit inside the given bounding
      * rectangle, given this items current rotation. Legitimately means that
      * whether this item is allowed to be distorted, inverted, resized, etc.
      */
     QRect maxInnerRectangle(const QRect &outerRect) const;
 
     ItemData itemData() const override;
 
     bool mousePressEvent(const EventInfo &eventInfo) override;
     bool mouseReleaseEvent(const EventInfo &eventInfo) override;
     bool mouseDoubleClickEvent(const EventInfo &eventInfo) override;
     bool mouseMoveEvent(const EventInfo &eventInfo) override;
     bool wheelEvent(const EventInfo &eventInfo) override;
     void enterEvent(QEvent *) override;
     void leaveEvent(QEvent *) override;
 
 public slots:
     /**
      * Rotate the item by the given amount (in radians)
      */
     void rotateBy(double dtheta);
     void parentMoved();
 
 signals:
     /**
      * Emitted when this item moves (translates or rotates)
      */
     void moved();
 
 protected slots:
     /**
      * Recalculate the combined mechanics info (e.g. when mass is changed, or child added)
      */
     void updateMechanicsInfoCombined();
 
 protected:
     void reparented(Item *oldItem, Item *newItem) override;
     void childAdded(Item *child) override;
     void childRemoved(Item *child) override;
     /**
      * Called when this item is resized, so that sub classes can do whatever
      */
     virtual void itemResized() {};
     /**
      * Sets the correct orientation on the painter
      */
     void initPainter(QPainter &p);
     /**
      * *Must* be called after calling initPainter, if initPainter was called
      */
     void deinitPainter(QPainter &p);
     void dataChanged() override;
     void itemPointsChanged() override
     {
         updateCanvasPoints();
     }
     /**
      * Calculates the setPoints required from the current m_itemPoints and the
      * current position / angle
      */
     void updateCanvasPoints();
 
     MechanicsDocument *p_mechanicsDocument;
     PositionInfo m_relativePosition; // Absolution position if not attached to a parent item, or otherwise relative to parent item
     MechanicsInfo m_mechanicsInfo;
     CombinedMechanicsInfo m_mechanicsInfoCombined;
 
 private:
     SelectionMode m_selectionMode;
 };
 
 #endif