A C++ Implementation of an Improved Contour Plotting Algorithm

// ContourGLDoc.cpp : implementation of the CContourGLDoc class
//

#include "stdafx.h"
#include "Contour.h"
#include "ContourGL.h"
#include "ContourGLDoc.h"

#ifdef LINE
	#undef LINE
#endif

#define LINE(a,b,c,d) line2(a,b,c,d)

void line2(double x1, double y1, double x2, double y2)
{
	glColor3f(0,0,0);
	glBegin(GL_LINES);
		glVertex2d(x1,y1);
		glVertex2d(x2,y2);
	glEnd();
}

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CContourGLDoc

IMPLEMENT_DYNCREATE(CContourGLDoc, CDocument)

BEGIN_MESSAGE_MAP(CContourGLDoc, CDocument)
	//{{AFX_MSG_MAP(CContourGLDoc)
		// NOTE - the ClassWizard will add and remove mapping macros here.
		//    DO NOT EDIT what you see in these blocks of generated code!
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CContourGLDoc construction/destruction

CContourGLDoc::CContourGLDoc()
{
	// TODO: add one-time construction code here

}

CContourGLDoc::~CContourGLDoc()
{
}

BOOL CContourGLDoc::OnNewDocument()
{
	if (!CDocument::OnNewDocument())
		return FALSE;

	// TODO: add reinitialization code here
	// (SDI documents will reuse this document)

	return TRUE;
}



/////////////////////////////////////////////////////////////////////////////
// CContourGLDoc serialization

void CContourGLDoc::Serialize(CArchive& ar)
{
	if (ar.IsStoring())
	{
		// TODO: add storing code here
	}
	else
	{
		// TODO: add loading code here
	}
}

/////////////////////////////////////////////////////////////////////////////
// CContourGLDoc diagnostics

#ifdef _DEBUG
void CContourGLDoc::AssertValid() const
{
	CDocument::AssertValid();
}

void CContourGLDoc::Dump(CDumpContext& dc) const
{
	CDocument::Dump(dc);
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CContourGLDoc commands

void CContourGLDoc::Draw()
{
	// Plotting strip generated by CLineStripList
	// generating info
	m_listContour.Generate();

	// draw line strips
	CLineStripList* pStripList;
	CLineStrip* pStrip;
	UINT i,index;
	CLineStripList::iterator pos;
	CLineStrip::iterator pos2;
	double pLimits[4];
	double x,y;

	m_listContour.GetLimits(pLimits);
	for (i=0;i<m_listContour.GetNPlanes();i++)
	{
		pStripList=m_listContour.GetLines(i);
		ASSERT(pStripList);
		for (pos=pStripList->begin(); pos != pStripList->end() ; pos++)
		{
			pStrip=(*pos);
			ASSERT(pStrip);
			if (pStrip->empty())
				continue;


			// putting point at start and end of strip
			glBegin(GL_POINTS);
				glColor4f(1,0,0,.8f);
				// retreiving index
				index=pStrip->front();
				// drawing
				x=m_listContour.GetXi(index);
				y=m_listContour.GetYi(index);
				glVertex2f((GLfloat)(pLimits[0]+x),(GLfloat)(pLimits[2]+y));
				// retreiving index
				glColor4f(0,0,1,.8f);
				index=pStrip->back();
				// drawing
				x=m_listContour.GetXi(index);
				y=m_listContour.GetYi(index);
				glVertex2f((GLfloat)(pLimits[0]+x),(GLfloat)(pLimits[2]+y));
			glEnd();

			glColor3f(i/(float)m_listContour.GetNPlanes(),
				i/(float)m_listContour.GetNPlanes(),
				1.f-i/(float)m_listContour.GetNPlanes());

			// filling strip if closed...
			glBegin(GL_LINE_STRIP);
			for (pos2=pStrip->begin(); pos2 != pStrip->end() ; pos2++)
			{
				// retreiving index
				index=(*pos2);
				// drawing
				x=m_listContour.GetXi(index);
				y=m_listContour.GetYi(index);

				glVertex2f((GLfloat)(pLimits[0]+x),(GLfloat)(pLimits[2]+y));
			}
			glEnd();
		}
	}
}

void CContourGLDoc::GetGLLimits(double pLimits[])
{
	// drawing
	m_listContour.GetLimits(pLimits);
}