Draw a Triangle

FileName : TriangleView.h

class CTriangleView : public CView
{
 ...
 CPoint tr[3],ct;
 int rad;
 double rd;
 CRect rc;
...
};


FileName : TriangleView.cpp


 #include "math.h"
...

CTriangleView::CTriangleView()
{
    // TODO: add construction code here
    rd=0.0174532935;
}

void CTriangleView::OnDraw(CDC* pDC)
{
    CTriangleDoc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);
    // TODO: add draw code for native data here
    int i=0;
    GetClientRect (rc);
    ct.x = (rc.left + rc.right )/2;
    ct.y = (rc.top + rc.bottom )/2;
    rad=ct.x/2;
    while(i<3)
    {
    tr[i].x = ct.x + rad * sin(i*120*rd);
    tr[i].y = ct.y - rad * cos(i*120*rd);
    i++;
    }
    pDC->Polygon (tr,3);
}

void CTriangleView::OnLButtonDown(UINT nFlags, CPoint point)
{
    // TODO: Add your message handler code here and/or call default
    int i=0;
   
    CClientDC *pDC = new CClientDC (this);
    ct.x = point.x;
    ct.y = point.y;
    rad=20;
    while(i<3)
    {
    tr[i].x = ct.x + rad * sin(i*120*rd);
    tr[i].y = ct.y - rad * cos(i*120*rd);
    i++;
    }
    pDC->Polygon (tr,3);
    CView::OnLButtonDown(nFlags, point);
}