5 #include "../detail/type_vec4.hpp" 
vec< 4, float, lowp > lowp_vec4
4 components vector of low single-qualifier floating-point numbers. 
vec< 4, float, mediump > mediump_vec4
4 components vector of medium single-qualifier floating-point numbers. 
vec< 4, float, highp > highp_vec4
4 components vector of high single-qualifier floating-point numbers.