opengl es - Max Varying Vectors and Floats for GLES 2.0 -

i trying figure out maximum number of varying vectors , uniforms can use on device opengl es 2.0 compatible. trying understand how max_varying_vectors works. if max_varying_vectors 8, mean can store 8 * 4 bytes of data varyings or mean can define 8 varyings irrespective of data type?

max_varying_vectors measured in units of 4-member float vectors (vec4). minimum guaranteed value of 8, can have 8 varyings of type vec4.

the rules on how other types fit available space complex. example max_varying_vectors 8, whole thing treated 2d array of 8 rows , 4 columns. space in array allocated varyings in order (which goes largest smallest), , rules depend on size of variable , size/location of empty space still available in array.

the exact rules fill 2.5 pages in glsl es 1.00 spec document. on pages 111-113. copying whole thing not make lot of sense, , i'm afraid can't turn simpler while still remaining accurate.