intial commit

source/mijin/util/bitflags.hpp

@@ -0,0 +1,92 @@
+
+#pragma once
+
+#if !defined(MIJIN_UTIL_BITFLAGS_HPP_INCLUDED)
+#define MIJIN_UTIL_BITFLAGS_HPP_INCLUDED 1
+
+#include <bit>
+#include <cstddef>
+
+namespace mijin
+{
+
+//
+// public defines
+//
+
+//
+// public constants
+//
+
+//
+// public types
+//
+
+template<typename TBits>
+struct BitFlags
+{
+    constexpr TBits& operator |=(const BitFlags& other) {
+        for (std::size_t idx = 0; idx < sizeof(TBits); ++idx) {
+            *(std::bit_cast<std::byte*>(asBits()) + idx) |= *(std::bit_cast<const std::byte*>(other.asBits()) + idx);
+        }
+        return *asBits();
+    }
+    constexpr TBits& operator &=(const BitFlags& other) {
+        for (std::size_t idx = 0; idx < sizeof(TBits); ++idx) {
+            *(std::bit_cast<std::byte*>(asBits()) + idx) &= *(std::bit_cast<const std::byte*>(other.asBits()) + idx);
+        }
+        return *asBits();
+    }
+
+    constexpr TBits& operator ^=(const BitFlags& other) {
+        for (std::size_t idx = 0; idx < sizeof(TBits); ++idx) {
+            *(std::bit_cast<std::byte*>(asBits()) + idx) ^= *(std::bit_cast<const std::byte*>(other.asBits()) + idx);
+        }
+        return *asBits();
+    }
+
+    constexpr TBits operator& (const BitFlags& other) const
+    {
+        TBits copy(*asBits());
+        copy &= other;
+        return copy;
+    }
+
+    constexpr TBits operator| (const BitFlags& other) const
+    {
+        TBits copy(*asBits());
+        copy |= other;
+        return copy;
+    }
+
+    constexpr TBits operator^ (const BitFlags& other) const
+    {
+        TBits copy(*asBits());
+        copy ^= other;
+        return copy;
+    }
+
+    constexpr operator bool() const {
+        for (std::size_t idx = 0; idx < sizeof(TBits); ++idx) {
+            if (*(std::bit_cast<const std::byte*>(asBits()) + idx) != std::byte(0)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    constexpr bool operator!() const {
+        return !static_cast<bool>(*this);
+    }
+private:
+    constexpr TBits* asBits() { return static_cast<TBits*>(this); }
+    constexpr const TBits* asBits() const { return static_cast<const TBits*>(this); }
+};
+
+//
+// public functions
+//
+
+} // namespace mijin
+
+#endif // !defined(MIJIN_UTIL_BITFLAGS_HPP_INCLUDED)