/// <summary>
/// Draw the user input control points and natural spline.
/// </summary>
private void DrawInteractive(Graphics g)
{
// Generate natural spline using the control points.
if (controlPoints.Count >= 3)
{
GameObject points = new NaturalSpline(controlPoints);
points.Render(g);
}
// Draw the control points.
foreach (Vector3D point in controlPoints)
{
g.FillEllipse(brush, (int)point.X - 4, (int)point.Y - 4, 8, 8);
}
}
/// <summary>
/// Draw the original NACA airfoil along with the approximate natural spline.
/// </summary>
private void DrawAirfoil(Graphics g)
{
// Label the x and y axes.
g.DrawString("Y", new Font("Arial", 10), System.Drawing.Brushes.Blue, new Point(0, 0));
g.DrawString("X", new Font("Arial", 10), System.Drawing.Brushes.Blue, new Point(800, 200));
// Draw th x and y axes.
g.DrawLine(System.Drawing.Pens.Red, 0, 200, 800, 200);
g.DrawLine(System.Drawing.Pens.Red, 0, 0, 0, 400);
if (initialized == false)
{
return;
}
// Draw the original NACA airfoil.
xl1 = 0;
yl1 = 200;
xu1 = 0;
yu1 = 200;
yc1 = 200;
xc1 = 0;
for (i = 0; i <= 100; i++)
{
xl2 = (int)(800 * xl[i]);
yl2 = 200 - (int)(800 * yl[i]);
g.DrawLine(System.Drawing.Pens.Red, xl1, yl1, xl2, yl2);
xl1 = xl2;
yl1 = yl2;
xu2 = (int)(800 * xu[i]);
yu2 = 200 - (int)(800 * yu[i]);
g.DrawLine(System.Drawing.Pens.Red, xu1, yu1, xu2, yu2);
xu1 = xu2;
yu1 = yu2;
xc2 = 8 * i;
yc2 = 200 - (int)(800 * yc[i]);
g.DrawLine(System.Drawing.Pens.Blue, xc1, yc1, xc2, yc2);
xc1 = xc2;
yc1 = yc2;
}
// Specify sample points for the natural spline.
int u0 = 100;
int u1 = 70;
int u2 = 45;
int u3 = 20;
int u4 = 6;
int u5 = 2;
int u6 = 0;
int l1 = 2;
int l2 = 6;
int l3 = 25;
int l4 = 60;
int l5 = 80;
int l6 = 100;
// Index the points from the original.
List <Vector3D> airfoil = new List <Vector3D>
{
new Vector3D((800 * xu[u0]), 200 - (800 * yu[u0]), 0),
new Vector3D((800 * xu[u1]), 200 - (800 * yu[u1]), 0),
new Vector3D((800 * xu[u2]), 200 - (800 * yu[u2]), 0),
new Vector3D((800 * xu[u3]), 200 - (800 * yu[u3]), 0),
new Vector3D((800 * xu[u4]), 200 - (800 * yu[u4]), 0),
new Vector3D((800 * xu[u5]), 200 - (800 * yu[u5]), 0),
new Vector3D((800 * xu[u6]), 200 - (800 * yu[u6]), 0),
new Vector3D((800 * xl[l1]), 200 - (800 * yl[l1]), 0),
new Vector3D((800 * xl[l2]), 200 - (800 * yl[l2]), 0),
new Vector3D((800 * xl[l3]), 200 - (800 * yl[l3]), 0),
new Vector3D((800 * xl[l4]), 200 - (800 * yl[l4]), 0),
new Vector3D((800 * xl[l5]), 200 - (800 * yl[l5]), 0),
new Vector3D((800 * xl[l6]), 200 - (800 * yl[l6]), 0),
};
List <Vector3D> camber = new List <Vector3D>
{
new Vector3D(8 * 0, 200 - (800 * yc[0]), 0),
new Vector3D(8 * 20, 200 - (800 * yc[20]), 0),
new Vector3D(8 * 60, 200 - (800 * yc[60]), 0),
new Vector3D(8 * 100, 200 - (800 * yc[100]), 0),
};
// Generate the natural splines.
GameObject airfoilSpline = new NaturalSpline(airfoil);
GameObject camberSpline = new NaturalSpline(camber);
// Draw the natural splines.
airfoilSpline.Render(g);
camberSpline.Render(g);
// Draw the control points.
foreach (Vector3D point in airfoil)
{
g.FillEllipse(brush, (int)point.X - 4, (int)point.Y - 4, 8, 8);
}
}