uniform sampler2D colorMap;


#define textureWidth 600.0
#define textureHeight 800.0	
#define texel_size_x 1.0 / textureWidth
#define texel_size_y 1.0 / textureHeight

vec4 texBlur( sampler2D tex, vec2 uv )
{
	vec2 f;

	f.x	= fract( uv.x * textureWidth );
	f.y	= fract( uv.y * textureHeight );

	vec4 t00 = texture2D( tex, uv + vec2( 0.0, 0.0 ));
	vec4 t10 = texture2D( tex, uv + vec2( texel_size_x, 0.0 ));
	vec4 tA = mix( t00, t10, f.x);

	vec4 t01 = texture2D( tex, uv + vec2( 0.0, texel_size_y ) );
	vec4 t11 = texture2D( tex, uv + vec2( texel_size_x, texel_size_y ) );

	vec4 tB = mix( t01, t11, f.x );

	return mix( tA, tB, f.y );
}			

void main (void)
{
	gl_FragColor = texBlur( colorMap, gl_TexCoord[0].xy);
}