include/wx/affinematrix2dbase.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:         wx/affinematrix2dbase.h
   3 // Purpose:      Common interface for 2D transformation matrices.
   4 // Author:       Catalin Raceanu
   5 // Created:      2011-04-06
   6 // Copyright:    (c) wxWidgets team
   7 // Licence:      wxWidgets licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 #ifndef _WX_AFFINEMATRIX2DBASE_H_
  11 #define _WX_AFFINEMATRIX2DBASE_H_
  12
  13 #include "wx/defs.h"
  14 #include "wx/geometry.h"
  15
  16 struct wxMatrix2D
  17 {
  18     wxMatrix2D(wxDouble v11 = 1,
  19                wxDouble v12 = 0,
  20                wxDouble v21 = 0,
  21                wxDouble v22 = 1)
  22     {
  23         m_11 = v11; m_12 = v12;
  24         m_21 = v21; m_22 = v22;
  25     }
  26
  27     wxDouble m_11, m_12, m_21, m_22;
  28 };
  29
  30 // A 2x3 matrix representing an affine 2D transformation.
  31 //
  32 // This is an abstract base class implemented by wxAffineMatrix2D only so far,
  33 // but in the future we also plan to derive wxGraphicsMatrix from it (it should
  34 // also be documented then as currently only wxAffineMatrix2D itself is).
  35 class WXDLLIMPEXP_CORE wxAffineMatrix2DBase
  36 {
  37 public:
  38     wxAffineMatrix2DBase() {}
  39     virtual ~wxAffineMatrix2DBase() {}
  40
  41     // sets the matrix to the respective values
  42     virtual void Set(const wxMatrix2D& mat2D, const wxPoint2DDouble& tr) = 0;
  43
  44     // gets the component valuess of the matrix
  45     virtual void Get(wxMatrix2D* mat2D, wxPoint2DDouble* tr) const = 0;
  46
  47     // concatenates the matrix
  48     virtual void Concat(const wxAffineMatrix2DBase& t) = 0;
  49
  50     // makes this the inverse matrix
  51     virtual bool Invert() = 0;
  52
  53     // return true if this is the identity matrix
  54     virtual bool IsIdentity() const = 0;
  55
  56     // returns true if the elements of the transformation matrix are equal ?
  57     virtual bool IsEqual(const wxAffineMatrix2DBase& t) const = 0;
  58     bool operator==(const wxAffineMatrix2DBase& t) const { return IsEqual(t); }
  59     bool operator!=(const wxAffineMatrix2DBase& t) const { return !IsEqual(t); }
  60
  61
  62     //
  63     // transformations
  64     //
  65
  66     // add the translation to this matrix
  67     virtual void Translate(wxDouble dx, wxDouble dy) = 0;
  68
  69     // add the scale to this matrix
  70     virtual void Scale(wxDouble xScale, wxDouble yScale) = 0;
  71
  72     // add the rotation to this matrix (counter clockwise, radians)
  73     virtual void Rotate(wxDouble ccRadians) = 0;
  74
  75     // add mirroring to this matrix
  76     void Mirror(int direction = wxHORIZONTAL)
  77     {
  78         wxDouble x = (direction & wxHORIZONTAL) ? -1 : 1;
  79         wxDouble y = (direction & wxVERTICAL) ? -1 : 1;
  80         Scale(x, y);
  81     }
  82
  83
  84     // applies that matrix to the point
  85     wxPoint2DDouble TransformPoint(const wxPoint2DDouble& src) const
  86     {
  87         return DoTransformPoint(src);
  88     }
  89
  90     void TransformPoint(wxDouble* x, wxDouble* y) const
  91     {
  92         wxCHECK_RET( x && y, "Can't be NULL" );
  93
  94         const wxPoint2DDouble dst = DoTransformPoint(wxPoint2DDouble(*x, *y));
  95         *x = dst.m_x;
  96         *y = dst.m_y;
  97     }
  98
  99     // applies the matrix except for translations
 100     wxPoint2DDouble TransformDistance(const wxPoint2DDouble& src) const
 101     {
 102         return DoTransformDistance(src);
 103     }
 104
 105     void TransformDistance(wxDouble* dx, wxDouble* dy) const
 106     {
 107         wxCHECK_RET( dx && dy, "Can't be NULL" );
 108
 109         const wxPoint2DDouble
 110             dst = DoTransformDistance(wxPoint2DDouble(*dx, *dy));
 111         *dx = dst.m_x;
 112         *dy = dst.m_y;
 113     }
 114
 115 protected:
 116     virtual
 117         wxPoint2DDouble DoTransformPoint(const wxPoint2DDouble& p) const = 0;
 118     virtual
 119         wxPoint2DDouble DoTransformDistance(const wxPoint2DDouble& p) const = 0;
 120 };
 121
 122 #endif // _WX_AFFINEMATRIX2DBASE_H_