const int POINTS = 8;
cSurfaceData i_Data1 = new cSurfaceData(eSurfaceMode.Lines, POINTS, POINTS, new cColorScheme(3, Color.Orange));
cSurfaceData i_Data2 = new cSurfaceData(eSurfaceMode.Lines, POINTS, POINTS, new cColorScheme(2, Color.Black));

for (int C=0; C<POINTS; C++)
{
    for (int R=0; R<POINTS; R++)
    {
        double d_X = (C - POINTS / 2.3) / (POINTS / 5.5);
        double d_Y = (R - POINTS / 2.3) / (POINTS / 5.5);
        double d_Radius = Math.Sqrt(d_X * d_X + d_Y * d_Y);
        double d_Z = Math.Cos(d_Radius) + 1.0;

        i_Data1.SetPointAt(C, R,  d_X, d_Y, d_Z);
        i_Data2.SetPointAt(C, R,  d_X, d_Y, d_Z * 0.6);
    }
}

cMessgData i_Mesg1 = new cMessgData("Graph with error data",   10, -10, Color.Orange);
cMessgData i_Mesg2 = new cMessgData("Graph with correct data", 10, -27, Color.Black);

graph3D.BeginUpdate();
graph3D.AddRenderData (i_Data1);
graph3D.AddRenderData (i_Data2);
graph3D.AddMessageData(i_Mesg1);
graph3D.AddMessageData(i_Mesg2);
graph3D.EndUpdate(eNormalize.MaintainXY);