wxWidgets/contrib/src/canvas/bbox.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        bbox.cpp
// Author:      Klaas Holwerda
// Created:     XX/XX/XX
// Copyright:   2000 (c) Klaas Holwerda
// Licence:     wxWindows Licence
/////////////////////////////////////////////////////////////////////////////

#ifdef __GNUG__
    #pragma implementation "bbox.cpp"
#endif

// For compilers that support precompilation, includes "wx/wx.h".
#include "wx/wxprec.h"

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

#include "wx/canvas/bbox.h"

wxBoundingBox::wxBoundingBox()
{
    m_minx = m_miny = m_maxx =  m_maxy = 0.0;
    m_validbbox = FALSE;
}


wxBoundingBox::wxBoundingBox(wxBoundingBox &other)
{
    m_minx = other.m_minx;
    m_miny = other.m_miny;
    m_maxx = other.m_maxx;
    m_maxy = other.m_maxy;
    m_validbbox= other.m_validbbox;
}


wxBoundingBox::wxBoundingBox(const wxPoint2DDouble& a)
{
    m_minx = a.m_x;
    m_maxx = a.m_x;
    m_miny = a.m_y;
    m_maxy = a.m_y;
    m_validbbox = TRUE;
}

wxBoundingBox::wxBoundingBox(double xmin, double ymin, double xmax, double ymax)
{
    m_minx = xmin;
    m_miny = ymin;
    m_maxx = xmax;
    m_maxy = ymax;
    m_validbbox = TRUE;
}

// This function checks if two bboxes intersect
bool wxBoundingBox::And(wxBoundingBox *_bbox, double Marge)
{
    assert (m_validbbox == TRUE);
    assert (_bbox->GetValid());
    m_minx = wxMax(m_minx, _bbox->m_minx);
    m_maxx = wxMin(m_maxx, _bbox->m_maxx);
    m_miny = wxMax(m_miny, _bbox->m_miny);
    m_maxy = wxMin(m_maxy, _bbox->m_maxy);
    return (bool)
             (
             ((m_minx - Marge) < (m_maxx + Marge)) &&
             ((m_miny - Marge) < (m_maxy + Marge))
             );
}

// Shrink the boundingbox with the given marge
void wxBoundingBox::Shrink(const double Marge)
{
    assert (m_validbbox == TRUE);

    m_minx += Marge;
    m_maxx -= Marge;
    m_miny += Marge;
    m_maxy -= Marge;
}


// Expand the boundingbox with another boundingbox
void wxBoundingBox::Expand(const wxBoundingBox &other)
{
    if (!m_validbbox)
    {
        *this=other;
    }
    else
    {
        m_minx = wxMin(m_minx, other.m_minx);
        m_maxx = wxMax(m_maxx, other.m_maxx);
        m_miny = wxMin(m_miny, other.m_miny);
        m_maxy = wxMax(m_maxy, other.m_maxy);
    }
}


// Expand the boundingbox with a point
void wxBoundingBox::Expand(const wxPoint2DDouble& a_point)
{
    if (!m_validbbox)
    {
        m_minx = m_maxx = a_point.m_x;
        m_miny = m_maxy = a_point.m_y;
        m_validbbox=TRUE;
    }
    else
    {
        m_minx = wxMin(m_minx, a_point.m_x);
        m_maxx = wxMax(m_maxx, a_point.m_x);
        m_miny = wxMin(m_miny, a_point.m_y);
        m_maxy = wxMax(m_maxy, a_point.m_y);
    }
}

// Expand the boundingbox with a point
void wxBoundingBox::Expand(double x,double y)
{
    if (!m_validbbox)
    {
        m_minx = m_maxx = x;
        m_miny = m_maxy = y;
        m_validbbox=TRUE;
    }
    else
    {
        m_minx = wxMin(m_minx, x);
        m_maxx = wxMax(m_maxx, x);
        m_miny = wxMin(m_miny, y);
        m_maxy = wxMax(m_maxy, y);
    }
}


// Expand the boundingbox with two points
void wxBoundingBox::Expand(const wxPoint2DDouble& a, const wxPoint2DDouble& b)
{
    Expand(a);
    Expand(b);
}

// Enlarge the boundingbox with the given marge
void wxBoundingBox::EnLarge(const double marge)
{
    if (!m_validbbox)
    {
        m_minx = m_maxx = marge;
        m_miny = m_maxy = marge;
        m_validbbox=TRUE;
    }
    else
    {
        m_minx -= marge;
        m_maxx += marge;
        m_miny -= marge;
        m_maxy += marge;
    }
}

// Calculates if two boundingboxes intersect. If so, the function returns _ON.
// If they do not intersect, two scenario's are possible:
// other is outside this -> return _OUT
// other is inside this -> return _IN
OVERLAP wxBoundingBox::Intersect(wxBoundingBox &other, double Marge)
{
    assert (m_validbbox == TRUE);

    // other boundingbox must exist
    assert (&other);

    if (((m_minx - Marge) > (other.m_maxx + Marge)) ||
         ((m_maxx + Marge) < (other.m_minx - Marge)) ||
         ((m_maxy + Marge) < (other.m_miny - Marge)) ||
         ((m_miny - Marge) > (other.m_maxy + Marge)))
        return _OUT;

    // Check if other.bbox is inside this bbox
    if ((m_minx <= other.m_minx) &&
         (m_maxx >= other.m_maxx) &&
         (m_maxy >= other.m_maxy) &&
         (m_miny <= other.m_miny))
        return _IN;

    // Boundingboxes intersect
    return _ON;
}


// Checks if a line intersects the boundingbox
bool wxBoundingBox::LineIntersect(const wxPoint2DDouble& begin, const wxPoint2DDouble& end )
{
    assert (m_validbbox == TRUE);

    return (bool)
              !(((begin.m_y > m_maxy) && (end.m_y > m_maxy)) ||
                ((begin.m_y < m_miny) && (end.m_y < m_miny)) ||
                ((begin.m_x > m_maxx) && (end.m_x > m_maxx)) ||
                ((begin.m_x < m_minx) && (end.m_x < m_minx)));
}


// Is the given point in the boundingbox ??
bool wxBoundingBox::PointInBox(double x, double y, double Marge)
{
    assert (m_validbbox == TRUE);

    if (  x >= (m_minx - Marge) && x <= (m_maxx + Marge) &&
            y >= (m_miny - Marge) && y <= (m_maxy + Marge) )
            return TRUE;
    return FALSE;
}


//
// Is the given point in the boundingbox ??
//
bool wxBoundingBox::PointInBox(const wxPoint2DDouble& a, double Marge)
{
    assert (m_validbbox == TRUE);

    return PointInBox(a.m_x, a.m_y, Marge);
}


wxPoint2DDouble wxBoundingBox::GetMin()
{
    assert (m_validbbox == TRUE);

    return wxPoint2DDouble(m_minx, m_miny);
}


wxPoint2DDouble wxBoundingBox::GetMax()
{
    assert (m_validbbox == TRUE);

    return wxPoint2DDouble(m_maxx, m_maxy);
}

bool wxBoundingBox::GetValid() const
{
    return m_validbbox;
}

void wxBoundingBox::SetMin(double px, double py)
{
    m_minx = px;
    m_miny = py;
    if (!m_validbbox)
    {
        m_maxx = px;
        m_maxy = py;
        m_validbbox = TRUE;
    }
}

void wxBoundingBox::SetMax(double px, double py)
{
    m_maxx = px;
    m_maxy = py;
    if (!m_validbbox)
    {
        m_minx = px;
        m_miny = py;
        m_validbbox = TRUE;
    }
}

void wxBoundingBox::SetValid(bool value)
{
    m_validbbox = value;
}

// adds an offset to the boundingbox
// usage : a_boundingbox.Translate(a_point);
void wxBoundingBox::Translate(wxPoint2DDouble& offset)
{
    assert (m_validbbox == TRUE);

    m_minx += offset.m_x;
    m_maxx += offset.m_x;
    m_miny += offset.m_y;
    m_maxy += offset.m_y;
}


// clears the bounding box settings
void wxBoundingBox::Reset()
{
    m_minx = 0.0;
    m_maxx = 0.0;
    m_miny = 0.0;
    m_maxy = 0.0;
    m_validbbox = FALSE;
}


void wxBoundingBox::SetBoundingBox(const wxPoint2DDouble& a_point)
{
    m_minx = a_point.m_x;
    m_maxx = a_point.m_x;
    m_miny = a_point.m_y;
    m_maxy = a_point.m_y;
}


// Expands the boundingbox with the given point
// usage : a_boundingbox = a_boundingbox + pointer_to_an_offset;
wxBoundingBox& wxBoundingBox::operator+(wxBoundingBox &other)
{
    assert (m_validbbox == TRUE);
    assert (other.GetValid());

    Expand(other);
    return *this;
}


// makes a boundingbox same as the other
wxBoundingBox& wxBoundingBox::operator=( const wxBoundingBox &other)
{
    assert (other.GetValid());

    m_minx = other.m_minx;
    m_maxx = other.m_maxx;
    m_miny = other.m_miny;
    m_maxy = other.m_maxy;
    m_validbbox = other.m_validbbox;
    return *this;
}

void wxBoundingBox::MapBbox( const wxTransformMatrix& matrix)
{
    assert (m_validbbox == TRUE);

    double x1,y1,x2,y2,x3,y3,x4,y4;

    matrix.TransformPoint( m_minx, m_miny, x1, y1 );
    matrix.TransformPoint( m_minx, m_maxy, x2, y2 );
    matrix.TransformPoint( m_maxx, m_maxy, x3, y3 );
    matrix.TransformPoint( m_maxx, m_miny, x4, y4 );

    double xmin = wxMin(x1,x2);
    xmin = wxMin(xmin,x3);
    xmin = wxMin(xmin,x4);

    double xmax = wxMax( x1, x2);
    xmax = wxMax(xmax,x3);
    xmax = wxMax(xmax,x4);

    double ymin = wxMin(y1, y2);
    ymin = wxMin(ymin,y3);
    ymin = wxMin(ymin,y4);

    double ymax = wxMax(y1,y2);
    ymax = wxMax(ymax,y3);
    ymax = wxMax(ymax,y4);

    // Use these min and max values to set the new boundingbox
    m_minx = xmin;
    m_miny = ymin;
    m_maxx = xmax;
    m_maxy = ymax;
}