Learning examples in GodBolt
In hlsl, cbuffers cannot cross the 16-byte boundary between members. If one member were to cross, it is simply moved to the next boundary. You need to make sure that your CPU side struct that you memcpy to the buffer follows this rule, the compiler wont do it for you!
Find if a type exists in a param pack only using templates logic
template <typename T, typename... Ts>
struct IndexOf<T, TypePack<T, Ts...>> {
template <typename T, typename U, typename... Ts>
struct IndexOf<T, TypePack<U, Ts...>> {
// recurrsively call, after having stripped the top type off, add to count
IndexOf is called via <type_you_want_to_serach_for, param_pack>. The template specialization <T, Typepack<T, Ts...>> is a better fit than <T, Typepack<U, Ts...>> if they are the same type, as T remains constant