   cg and any function
  Hy.I have a hlsl shader to convert to cg.My problem is test if a float4 have all the component to 0(float4(0,0,0,0)).In hlsl i use the any function , but in cg?thanks.   
float4 v(0.0, 0.0, 0.0, 0.0);if( dot(v,v) == 0.0 ) {    // all components are 0}