From c44dba78cb3ad4458fe3abb75695967afb763c27 Mon Sep 17 00:00:00 2001
From: Andrzej Kapolka <drzej.k@gmail.com>
Date: Thu, 5 Jun 2014 15:32:55 -0700
Subject: [PATCH] Provide a reasonably painless way to stream enums that aren't
 object properties.

---
 libraries/metavoxels/src/Bitstream.h    | 34 ++++++++++++++++++++++---
 tests/metavoxels/src/MetavoxelTests.cpp |  7 +++--
 tests/metavoxels/src/MetavoxelTests.h   |  3 +++
 3 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/libraries/metavoxels/src/Bitstream.h b/libraries/metavoxels/src/Bitstream.h
index 146713910f..9945284775 100644
--- a/libraries/metavoxels/src/Bitstream.h
+++ b/libraries/metavoxels/src/Bitstream.h
@@ -1037,12 +1037,12 @@ public:
 };
 
 /// Macro for registering simple type streamers.
-#define REGISTER_SIMPLE_TYPE_STREAMER(x) static int x##Streamer = \
-    Bitstream::registerTypeStreamer(qMetaTypeId<x>(), new SimpleTypeStreamer<x>());
+#define REGISTER_SIMPLE_TYPE_STREAMER(X) static int X##Streamer = \
+    Bitstream::registerTypeStreamer(qMetaTypeId<X>(), new SimpleTypeStreamer<X>());
 
 /// Macro for registering collection type streamers.
-#define REGISTER_COLLECTION_TYPE_STREAMER(x) static int x##Streamer = \
-    Bitstream::registerTypeStreamer(qMetaTypeId<x>(), new CollectionTypeStreamer<x>());
+#define REGISTER_COLLECTION_TYPE_STREAMER(X) static int x##Streamer = \
+    Bitstream::registerTypeStreamer(qMetaTypeId<X>(), new CollectionTypeStreamer<X>());
 
 /// Declares the metatype and the streaming operators.  The last lines
 /// ensure that the generated file will be included in the link phase. 
@@ -1077,6 +1077,25 @@ public:
     _Pragma(STRINGIFY(unused(_TypePtr##X)))
 #endif
 
+#define DECLARE_ENUM_METATYPE(S, N) Q_DECLARE_METATYPE(S::N) \
+    Bitstream& operator<<(Bitstream& out, const S::N& obj); \
+    Bitstream& operator>>(Bitstream& in, S::N& obj); \
+    template<> inline void Bitstream::writeRawDelta(const S::N& value, const S::N& reference) { *this << value; } \
+    template<> inline void Bitstream::readRawDelta(S::N& value, const S::N& reference) { *this >> value; }
+
+#define IMPLEMENT_ENUM_METATYPE(S, N) \
+    static int S##N##MetaTypeId = registerEnumMetaType<S::N>(S::staticMetaObject.enumerator( \
+        S::staticMetaObject.indexOfEnumerator(#N))); \
+    Bitstream& operator<<(Bitstream& out, const S::N& obj) { \
+        static int bits = static_cast<const EnumTypeStreamer*>(Bitstream::getTypeStreamer(qMetaTypeId<S::N>()))->getBits(); \
+        return out.write(&obj, bits); \
+    } \
+    Bitstream& operator>>(Bitstream& in, S::N& obj) { \
+        static int bits = static_cast<const EnumTypeStreamer*>(Bitstream::getTypeStreamer(qMetaTypeId<S::N>()))->getBits(); \
+        obj = (S::N)0; \
+        return in.read(&obj, bits); \
+    }
+    
 /// Registers a simple type and its streamer.
 template<class T> int registerSimpleMetaType() {
     int type = qRegisterMetaType<T>();
@@ -1084,6 +1103,13 @@ template<class T> int registerSimpleMetaType() {
     return type;
 }
 
+/// Registers an enum type and its streamer.
+template<class T> int registerEnumMetaType(const QMetaEnum& metaEnum) {
+    int type = qRegisterMetaType<T>();
+    Bitstream::registerTypeStreamer(type, new EnumTypeStreamer(metaEnum));
+    return type;
+}
+
 /// Registers a streamable type and its streamer.
 template<class T> int registerStreamableMetaType() {
     int type = qRegisterMetaType<T>();
diff --git a/tests/metavoxels/src/MetavoxelTests.cpp b/tests/metavoxels/src/MetavoxelTests.cpp
index 603f63b587..cb1b5c7900 100644
--- a/tests/metavoxels/src/MetavoxelTests.cpp
+++ b/tests/metavoxels/src/MetavoxelTests.cpp
@@ -20,6 +20,8 @@
 REGISTER_META_OBJECT(TestSharedObjectA)
 REGISTER_META_OBJECT(TestSharedObjectB)
 
+IMPLEMENT_ENUM_METATYPE(TestSharedObjectA, TestEnum)
+
 MetavoxelTests::MetavoxelTests(int& argc, char** argv) :
     QCoreApplication(argc, argv) {
 }
@@ -80,6 +82,7 @@ static TestMessageC createRandomMessageC() {
     message.bar = rand();
     message.baz = randFloat();
     message.bong.foo = createRandomBytes();
+    message.bong.baz = getRandomTestEnum();
     return message;
 }
 
@@ -252,7 +255,7 @@ static QVariant createRandomMessage() {
             return QVariant::fromValue(message);
         }
         case 1: {
-            TestMessageB message = { createRandomBytes(), createRandomSharedObject() };
+            TestMessageB message = { createRandomBytes(), createRandomSharedObject(), getRandomTestEnum() };
             return QVariant::fromValue(message); 
         }
         case 2:
@@ -273,7 +276,7 @@ static bool messagesEqual(const QVariant& firstMessage, const QVariant& secondMe
     } else if (type == TestMessageB::Type) {
         TestMessageB first = firstMessage.value<TestMessageB>();
         TestMessageB second = secondMessage.value<TestMessageB>();
-        return first.foo == second.foo && equals(first.bar, second.bar);
+        return first.foo == second.foo && equals(first.bar, second.bar) && first.baz == second.baz;
         
     } else if (type == TestMessageC::Type) {
         return firstMessage.value<TestMessageC>() == secondMessage.value<TestMessageC>();
diff --git a/tests/metavoxels/src/MetavoxelTests.h b/tests/metavoxels/src/MetavoxelTests.h
index 5e020b1e60..ffd1311f00 100644
--- a/tests/metavoxels/src/MetavoxelTests.h
+++ b/tests/metavoxels/src/MetavoxelTests.h
@@ -106,6 +106,8 @@ private:
     TestFlags _bong;
 };
 
+DECLARE_ENUM_METATYPE(TestSharedObjectA, TestEnum)
+
 /// Another simple shared object.
 class TestSharedObjectB : public SharedObject {
     Q_OBJECT
@@ -169,6 +171,7 @@ public:
     
     STREAM QByteArray foo;
     STREAM SharedObjectPointer bar;
+    STREAM TestSharedObjectA::TestEnum baz;
 };
 
 DECLARE_STREAMABLE_METATYPE(TestMessageB)