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/*!

\title Screen Space AO
\page screen-space-ao-effect.html
\ingroup qt3dstudio-best-practices

Screen space ambient occlusion efficiently approximates the ambient occlusion of you layer
in real time. It is independent from the layers complexity and works with dynamic scenes.

\image effects-screen-space-ao.png

\table
  \header
    \li
      Pros
    \li
      Cons
  \row
    \li
      \list
        \li
          Independent from scene complexity.
        \li
          No data pre-processing needed.
        \li
          Works with dynamic scenes.
        \li
          Works in the same consistent way for every pixel on the screen.
        \li
          No CPU usage.
      \endlist
    \li
      \list
        \li
          Rather local and in many cases view-dependent, as it is dependent on
          adjacent texel depths which may be generated by any geometry whatsoever.
        \li
          Hard to correctly smooth/blur out the noise without bleeding onto objects.
      \endlist
\endtable

\table
  \header
    \li Property
    \li Description
  \row
    \li
      Filter Size
    \li
      Controls the shadows size.
  \row
    \li
      Distance Scale
    \li
      How strong the shadows are.
  \row
    \li
      Distance Bias
    \li
      Controls distance offset.
\endtable


\section1 Usage

The layer which the effect is applied to requires depth prepass for the effect to work.
Make sure in your layer's advanced options "disable depth prepass" is unchecked.

*/