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
  40     // sets the matrix to the respective values
  41     virtual void Set(const wxMatrix2D& mat2D, const wxPoint2DDouble& tr) = 0;
  42
  43     // gets the component valuess of the matrix
  44     virtual void Get(wxMatrix2D* mat2D, wxPoint2DDouble* tr) const = 0;
  45
  46     // concatenates the matrix
  47     virtual void Concat(const wxAffineMatrix2DBase& t) = 0;
  48
  49     // makes this the inverse matrix
  50     virtual bool Invert() = 0;
  51
  52     // return true if this is the identity matrix
  53     virtual bool IsIdentity() const = 0;
  54
  55     // returns true if the elements of the transformation matrix are equal ?
  56     virtual bool IsEqual(const wxAffineMatrix2DBase& t) const = 0;
  57     bool operator==(const wxAffineMatrix2DBase& t) const { return IsEqual(t); }
  58     bool operator!=(const wxAffineMatrix2DBase& t) const { return !IsEqual(t); }
  59
  60
  61     //
  62     // transformations
  63     //
  64
  65     // add the translation to this matrix
  66     virtual void Translate(wxDouble dx, wxDouble dy) = 0;
  67
  68     // add the scale to this matrix
  69     virtual void Scale(wxDouble xScale, wxDouble yScale) = 0;
  70
  71     // add the rotation to this matrix (counter clockwise, radians)
  72     virtual void Rotate(wxDouble ccRadians) = 0;
  73
  74     // add mirroring to this matrix
  75     void Mirror(int direction = wxHORIZONTAL)
  76     {
  77         wxDouble x = (direction & wxHORIZONTAL) ? -1 : 1;
  78         wxDouble y = (direction & wxVERTICAL) ? -1 : 1;
  79         Scale(x, y);
  80     }
  81
  82
  83     // applies that matrix to the point
  84     wxPoint2DDouble TransformPoint(const wxPoint2DDouble& src) const
  85     {
  86         return DoTransformPoint(src);
  87     }
  88
  89     void TransformPoint(wxDouble* x, wxDouble* y) const
  90     {
  91         wxCHECK_RET( x && y, "Can't be NULL" );
  92
  93         const wxPoint2DDouble dst = DoTransformPoint(wxPoint2DDouble(*x, *y));
  94         *x = dst.m_x;
  95         *y = dst.m_y;
  96     }
  97
  98     // applies the matrix except for translations
  99     wxPoint2DDouble TransformDistance(const wxPoint2DDouble& src) const
 100     {
 101         return DoTransformDistance(src);
 102     }
 103
 104     void TransformDistance(wxDouble* dx, wxDouble* dy) const
 105     {
 106         wxCHECK_RET( dx && dy, "Can't be NULL" );
 107
 108         const wxPoint2DDouble
 109             dst = DoTransformDistance(wxPoint2DDouble(*dx, *dy));
 110         *dx = dst.m_x;
 111         *dy = dst.m_y;
 112     }
 113
 114 protected:
 115     virtual
 116         wxPoint2DDouble DoTransformPoint(const wxPoint2DDouble& p) const = 0;
 117     virtual
 118         wxPoint2DDouble DoTransformDistance(const wxPoint2DDouble& p) const = 0;
 119 };
 120
 121 #endif // _WX_AFFINEMATRIX2DBASE_H_