text: /*  RetroArch - A frontend for libretro.
   *  Copyright (C) 2014-2018 - Ali Bouhlel
   *
   *  RetroArch is free software: you can redistribute it and/or modify it under the terms
   *  of the GNU General Public License as published by the Free Software Found-
   *  ation, either version 3 of the License, or (at your option) any later version.
   *
   *  RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
   *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
   *  PURPOSE.  See the GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along with RetroArch.
   *  If not, see <http://www.gnu.org/licenses/>.
   */
  
  #define SRC(...) #__VA_ARGS__
  SRC(
  
     Texture2D<float4> t0;
     RWTexture2D<float4> u0;
     sampler s0;
  
     cbuffer CBr
     {
         uint src_level;
         float2 texel_size;
     }
  
     static float w[4]= {0.090845, 0.409155, 0.409155, 0.090845};
     [numthreads(8, 8, 1)]
     void CSMain(uint3 DTid : SV_DispatchThreadID)
     {
        int i;
        int j;
        float4 c = 0.0f;
        for (i = 0; i < 4; i++)
           for (j = 0; j < 4; j++)
           {
              float4 c0 = t0.SampleLevel(s0, texel_size * (DTid.xy + 0.5f * float2(i - 0.5f,j - 0.5f)), src_level);
              c0.rgb *= c0.a;
              c += w[i] * w[j] * c0;
           }
        c.rgb /= c.a;
  
        u0[DTid.xy] = c;
        return;
  
     }
  )
  