message: Use unsigned for SIMD
diff: #ifndef VSNRAY_RANDOM_GENERATOR_H
  #define VSNRAY_RANDOM_GENERATOR_H 1
  -#include <cstddef>
  #include <type_traits>
  #if defined(__CUDACC__)
  @@ -94,7 +93,7 @@ public:
  }
  // TODO: maybe don't have a random_generatorN at all?
  - VSNRAY_FUNC generator_type& get_generator(size_t i)
  + VSNRAY_FUNC generator_type& get_generator(unsigned i)
  {
  return generators_[i];
  }
  