shader_type canvas_item;

uniform sampler2D screen_texture : hint_screen_texture, repeat_disable, filter_nearest;

uniform float kernelOffset = 1;

void fragment() 
{
  vec2 pixelSize = SCREEN_PIXEL_SIZE * kernelOffset;
  
  vec4 blurred = vec4( 0, 0, 0, 0 );
  int kernel = 2;
  
  for ( int x = -kernel; x<= kernel; ++x )
  {
    for ( int y = -kernel; y<= kernel; ++y )
    {
      vec2 sampledUV = SCREEN_UV + pixelSize * vec2( float(x), float( y ) );
      vec4 value = textureLod( screen_texture, sampledUV, 0 );
      
      if ( ( value.r + value.g + value.b ) * 255.0 < 10.0 )
      {
        value.a = 0.0;
      }
      
      blurred += value;
    }
  }
  
  blurred /= float( kernel * kernel );
  
  
  COLOR = blurred;
  ;
}