public override void Draw()
{
viewport.Begin();
var cam = new LookAtCamera();
Matrix4x4 rot = Matrix4x4.CreateRotationX(viewport.CameraRotation.Y) *
Matrix4x4.CreateRotationY(viewport.CameraRotation.X);
var dir = Vector3.Transform(-Vector3.UnitZ, rot);
var to = Vector3.Zero;
cam.Update(viewport.RenderWidth, viewport.RenderHeight, viewport.CameraOffset, to, rot);
shader.SetViewProjection(cam);
var w = Matrix4x4.Identity;
var n = Matrix4x4.Identity;
shader.SetWorld(ref w, ref n);
shader.Shader.SetVector3(cameraPositionIndex, cam.Position);
tex.BindTo(0);
shader.UseProgram();
for (int i = 0; i < 6; i++)
{
sphere.GetDrawParameters((CubeMapFace)i, out int start, out int count, out _);
sphere.VertexBuffer.Draw(PrimitiveTypes.TriangleList, 0, start, count);
}
viewport.End();
}