#extension GL_ARB_texture_rectangle : enable

uniform sampler2DRect osgOcean_GaussianTexture;

void main( void )
{
   vec2 texCoordSample = vec2( 0.0 );

   vec4 color = 0.5 * texture2DRect( osgOcean_GaussianTexture, gl_TexCoord[0].st );

   texCoordSample.x = gl_TexCoord[0].x;
   texCoordSample.y = gl_TexCoord[0].y + 1.0;
   color += 0.25 * texture2DRect( osgOcean_GaussianTexture, texCoordSample);

   texCoordSample.y = gl_TexCoord[0].y - 1.0;
   color += 0.25 * texture2DRect( osgOcean_GaussianTexture, texCoordSample);

   gl_FragColor = color;
}