source: downloads/Samples/Media/materials/programs/Blur_ps.glsl @ 3

uniform sampler2D tex0;

varying vec2 texCoord[5];

void main()
{
        vec4 sum = texture2D(tex0, texCoord[0]) + 
                           texture2D(tex0, texCoord[1]) +
                           texture2D(tex0, texCoord[2]) + 
                           texture2D(tex0, texCoord[3]) +
                           texture2D(tex0, texCoord[4]);
        gl_FragColor = sum / 5.0;
}