title: HLSL mul() variables clarification
body: <p>The parameters for HLSL's mul( x, y) indicated <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/bb509628(v=vs.85).aspx" rel="noreferrer">here</a>: say that</p>
  
  <ul>
  <li>if x is a vector, it is treated as a row vector.</li>
  <li>if y is a vector, it is treated as a column vector.</li>
  </ul>
  
  <p>Does this then follow through meaning that:</p>
  
  <p>a.</p>
  
  <ul>
  <li>if x is a vector, y is treated as a <code>row-major matrix</code></li>
  <li>if y is a vector, x is treated as a <code>column-major matrix</code></li>
  </ul>
  
  <p>b. </p>
  
  <p>since ID3DXBaseEffect::SetMatrix() passes in a <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/bb205720(v=vs.85).aspx" rel="noreferrer"><code>row-major matrix</code></a>, hence I'd use the matrix passed into the shader in following order:</p>
  
  <p>ex. <code>Output.mPosition = mul( Input.mPosition, SetMatrix()value );</code> ?</p>
  
  <p>I'm just starting out with shaders and current relearning my matrix math. It would be nice if someone could clarify this.</p>