   Matrix Transformation (maybe i'm a little drunk today :)
  While i was writing a new class for a game, i've stumbled into a strange problem that I can't find reason or way to resolve.I have to draw a quad with a certain size. (quad defined as (0,0,0)-(1,0,0)-(0,1,0)-(1,1,0))I use the following matrix: ViewMatrix = Matrix.LookAtLH(new Vector3(0, 0, 1000), new Vector3(0, 0, 0), new Vector3(0, 1, 0));ProjectionMatrix = Matrix.OrthoLH(Parent.ScreenSize.Width, Parent.ScreenSize.Height, 0.1f, 1000f);WorldMatrix = Matrix.Scaling(Dimensioni.Width, Dimensioni.Height, 1) *Matrix.Translation(new Vector3((ScreenSize.Width / 2) - Posizione.X, (ScreenSize.Height / 2) - Posizione.Y, 0));This way I get a Quad that is basically upside down, the first vertex that should be the top-left one is the bottom-right one...Please note that i've used the same IDENTICAL matrix for another class, with the only difference that the World Matrix (only that) is calculated on the shader and it works...Maybe i'm lacking something...Any idea on the reason?   
  Resolved, it was a problem of passing parameters to the buffers on the effect.   