This code defines a function called OnLButtonDown that draws a blue polygon with red outline on a canvas when the left mouse button is clicked. It uses device context methods like SelectObject to choose a pen and brush and the Polygon method to draw the polygon defined by an array of 4 point coordinates.

1. Polygon

8. void CPolygonView::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
CClientDC dc(this);
CPen pen(PS_SOLID, 2, RGB(255, 0, 0));
dc.SelectObject(&pen);
CBrush brush(RGB(0, 0, 255));
dc.SelectObject(&brush);
CPoint a[10];
a[0] = CPoint(10, 10);
a[1] = CPoint(20, 190);
a[2] = CPoint(150, 180);
a[3] = CPoint(200, 30);
dc.Polygon(a, 4);
CView::OnLButtonDown(nFlags, point);
}