title: HLSL Coordinates system orientation
body: <p>This question may look pretty simple, but I cannot find how HLSL handles its own coordinates system.</p>
  
  <p>I only wish to know where is (0,0) located (Upper left corner or lower left corner), and since I am a total beginner with these shaders concepts, I am unable to deduct it by myself</p>
  
  <p>Thanks for your help!</p>