public void AddViewport(Viewport viewport)
{
// If the viewport doesn't have matrix, add this' by default
if (!viewport.matrix_set)
viewport.setMatrices(projMatrix, zoomMatrix);
viewports.Add(viewport);
}
private void openGLControl1_Layout(object sender, LayoutEventArgs e)
{
openGLControl1.viewports.Clear();
int w = openGLControl1.Width;
int h = openGLControl1.Height;
openGLControl1.default_viewport_size = new Rectangle(0, 0, 2 * w / 3, h);
Matrix4 projMatrix = Matrix4.CreateOrthographicOffCenter(-10, 10, -10, 10, 0.5f, 100);
Viewport up = new Viewport(2 * w / 3, 2 * h / 3, w / 3, h / 3);
up.objects.AddRange(openGLControl1.objects);
Matrix4 zoomMatrix = Matrix4.LookAt(new Vector3(0, 0, 10), new Vector3(0, 0.1f, 0), new Vector3(0, 0, 1));
up.setMatrices(projMatrix, zoomMatrix);
openGLControl1.AddViewport(up);
Viewport front = new Viewport(2 * w / 3, h / 3, w / 3, h / 3);
front.objects.AddRange(openGLControl1.objects);
zoomMatrix = Matrix4.LookAt(new Vector3(10, 0, 0), new Vector3(0, 0, 0), new Vector3(0, 0, 1));
front.setMatrices(projMatrix, zoomMatrix);
openGLControl1.AddViewport(front);
Viewport right = new Viewport(2 * w / 3, 0, w / 3, h / 3);
right.objects.AddRange(openGLControl1.objects);
zoomMatrix = Matrix4.LookAt(new Vector3(0, 10, 0), new Vector3(0, 0, 0), new Vector3(0, 0, 1));
right.setMatrices(projMatrix, zoomMatrix);
openGLControl1.AddViewport(right);
openGLControl1.Invalidate();
}