varying vec4 xlv_TEXCOORD0;
void main ()
{
  vec4 res;
  res.x = dFdx (xlv_TEXCOORD0.x);
  res.y = dFdx (xlv_TEXCOORD0.y);
  res.zw = fwidth (xlv_TEXCOORD0.xy);
  gl_FragData[0] = res;
}