Loading enums in a datablock...

#1 I eventually decided to just sidestep the problem. Since values in an enum are simply a fancy way of storing an integet, I made the datablock field an integer rather than an enum. Then when I copied the datablock fields into the structs, I converted the integer into an enum value, so I can use it in code.
This gave me a new problem - I'm getting an 'invalid packet from server' error when I start a mission. This problem doesn't seem to be connected to my custom clas, though, so it's probably just a script issue.
Next up is changing the integer datablock value into a string, so people can type in strings corresponding to the enum value names, instead of having to put in a number. I'll just use a block of if-elses to convert from a string to an enum value.

#2 I'd prefer the enum method as it is exactly what you want, only built in.

Did you provide an enum table?
excerpt:

static EnumTable::Enums enumRecoilStates[] =
{
   { ShapeBaseImageData::StateData::NoRecoil,     "NoRecoil" },
   { ShapeBaseImageData::StateData::LightRecoil,  "LightRecoil" },
   { ShapeBaseImageData::StateData::MediumRecoil, "MediumRecoil" },
   { ShapeBaseImageData::StateData::HeavyRecoil,  "HeavyRecoil" },
};
static EnumTable EnumRecoilState(4, &enumRecoilStates[0]);

#3 Hmm. That's a big resounding no. That would seem to solve the problem - thanks!
Is it just that I ask questions only you among the community know how to solve, or...? ;)

EDIT: nope. I get the exact same error as before. I'm having a look at debug information...
Okay, I have no idea what's going on. Do I have to do something special with the enum table?

EDIT: Think I found the problem - addField...

Okay, I got rid of this problem by using addField properly. Now I've gone back to the previous error that I ran into after making sure that this worked. Stupid invalid packets :[

#4 Post copies of your packData/unpackData methods for your datablock. Usually an invalid packet error is caused by these methods being out of sync.

#5 I thought that must have been it, because the error only shows up when I include my new class in the build. I can't spot anything, though...

For reference, here's the struct that the data is stored in:

struct WatchedField {
		const char* name;
		F32 minVal;
		F32 maxVal;
		F32 decayVal;
		enum WarnType {
			OnMin, OnMax,
			OnIncTo, OnDecTo,
			OnChange,
			NoWarn,
			NumWarnBits = 3,
		} warnType;
		F32 warnVals [4];
	} watchedFields [NumWatchedFields];

void RangedWeaponData::packData(BitStream* stream)
{
	Parent::packData(stream);

	if(stream->writeFlag(mProjectile))
		stream->writeRangedU32(packed? SimObjectId(mProjectile):
		mProjectile->getId(),DataBlockObjectIdFirst,DataBlockObjectIdLast);

	U32 i, j;
	for(i = 0; i < NumWatchedFields; i++)
	{
		if(stream->writeFlag(watchedFields[i].name && watchedFields[i].name[0]))
		{
			WatchedField& f = watchedFields[i];

			stream->writeString(f.name);
			stream->write(f.minVal);
			stream->write(f.maxVal);
			stream->write(f.decayVal);
			stream->writeInt(f.warnType,WatchedField::NumWarnBits);
			for(j = 0; j < 4; j++)
				stream->write(f.warnVals[j]);
		}
	}
}

void RangedWeaponData::unpackData(BitStream* stream)
{
	Parent::unpackData(stream);

	mProjectile = (stream->readFlag() ?
		(ProjectileData*)stream->readRangedU32(DataBlockObjectIdFirst,
		DataBlockObjectIdLast) : 0);

	U32 i, j;
	for(i = 0; i < NumWatchedFields; i++)
	{
		if(stream->readFlag())
		{
			WatchedField& f = watchedFields[i];

			f.name = stream->readSTString();
			stream->read(&f.minVal);
			stream->read(&f.maxVal);
			stream->read(&f.decayVal);
			f.warnType = (WatchedField::WarnType)stream->readInt(WatchedField::NumWarnBits);
			for(j = 0; j < 4; j++)
				stream->read(&f.warnVals[j]);
		}
	}
	watchedFieldsLoaded = true;
}

#6 Well that seems okay to me. Does your object have pack/unpack methods?

I'd put break points in your pack/unpack methods and make sure they seem to be writing/reading properly. Use your debugger to check values (make sure what is written is what is read).

#7 That's an idea - breakpointing the methods themselves. I wasn't sure wht could be causing the invalid packet thing (which dumps me from my level with a dialog), so I just searched for 'invalid packet' in the engine code and breakpointed all those to see which one was being called. None of them, apparently...

Here's the object pack/unpack, just in case:
(First, the struct objects use, which is different to the datablock struct:)

struct WatchedField {
		bool active;
		F32 val;
		F32 prevVal;
	} watchedFields[RangedWeaponData::NumWatchedFields];

U32 RangedWeapon::packUpdate(NetConnection *connection, U32 mask, BitStream *stream)
{
	U32 retMask = Parent::packUpdate(connection,mask,stream);

	stream->writeFlag(mPrimaryTriggerDown);
	stream->writeFlag(mSecondaryTriggerDown);

	stream->writeInt(mPrimaryTriggerOnTime,RangedWeapon::TriggerTimeBitSize);
	stream->writeInt(mPrimaryTriggerOffTime,RangedWeapon::TriggerTimeBitSize);
	stream->writeInt(mSecondaryTriggerOnTime,RangedWeapon::TriggerTimeBitSize);
	stream->writeInt(mSecondaryTriggerOffTime,RangedWeapon::TriggerTimeBitSize);

	if(mask & WatchedFieldUpdateMask)
	{
		for(U32 i = 0; i < RangedWeaponData::NumWatchedFields; i++)
			if(stream->writeFlag(watchedFields[i].active))
			{
				stream->write(watchedFields[i].val);
				stream->write(watchedFields[i].prevVal);
			}
	}

	return retMask;
}

void RangedWeapon::unpackUpdate(NetConnection *connection, BitStream *stream)
{
	Parent::unpackUpdate(connection,stream);

	mPrimaryTriggerDown = stream->readFlag();
	mSecondaryTriggerDown = stream->readFlag();

	mPrimaryTriggerOnTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);
	mPrimaryTriggerOffTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);
	mSecondaryTriggerOnTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);
	mSecondaryTriggerOffTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);

	for(U32 i = 0; i < RangedWeaponData::NumWatchedFields; i++)
	{
		watchedFields[i].active = stream->readFlag();
		if(watchedFields[i].active)
		{
			stream->read(&watchedFields[i].val);
			stream->read(&watchedFields[i].prevVal);
		}
	}
}

EDIT
From breakpoints on pack/unpack datablock methods, it seems that while an object for mProjectile is being packed, when it gets unpacked, it goes all screwy. Could that be a cause for an 'invalid packet'?

EDIT
This is really damn frustrating. The invalid packet thing only actually happens about half the time - sometimes my levels load fine, other times they get invalid packeted about a second after spawning. Makes it a bugger to debug properly. I'd still like to just breakpoint the piece of code that tells the scripts when there's an invalid packet.
And a nice addition to the engine would be to say which packet was invalid :P

#8 Well, from what I can tell from just the code, you seem to have the possibility of reading data that wasn't ever sent.

U32 RangedWeapon::packUpdate(NetConnection *connection, U32 mask, BitStream *stream)
{
	U32 retMask = Parent::packUpdate(connection,mask,stream);

	stream->writeFlag(mPrimaryTriggerDown);
	stream->writeFlag(mSecondaryTriggerDown);

	stream->writeInt(mPrimaryTriggerOnTime,RangedWeapon::TriggerTimeBitSize);
	stream->writeInt(mPrimaryTriggerOffTime,RangedWeapon::TriggerTimeBitSize);
	stream->writeInt(mSecondaryTriggerOnTime,RangedWeapon::TriggerTimeBitSize);
	stream->writeInt(mSecondaryTriggerOffTime,RangedWeapon::TriggerTimeBitSize);

        [b]// Check if we should sent watched field updates[/b]
	if(mask & WatchedFieldUpdateMask)
	{
		for(U32 i = 0; i < RangedWeaponData::NumWatchedFields; i++)
			if(stream->writeFlag(watchedFields[i].active))
			{
				stream->write(watchedFields[i].val);
				stream->write(watchedFields[i].prevVal);
			}
	}

	return retMask;
}

void RangedWeapon::unpackUpdate(NetConnection *connection, BitStream *stream)
{
	Parent::unpackUpdate(connection,stream);

	mPrimaryTriggerDown = stream->readFlag();
	mSecondaryTriggerDown = stream->readFlag();

	mPrimaryTriggerOnTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);
	mPrimaryTriggerOffTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);
	mSecondaryTriggerOnTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);
	mSecondaryTriggerOffTime = stream->readInt(RangedWeapon::TriggerTimeBitSize);

        [b]// Read watched field updates whether we sent them or not[/b]
	for(U32 i = 0; i < RangedWeaponData::NumWatchedFields; i++)
	{
		watchedFields[i].active = stream->readFlag();
		if(watchedFields[i].active)
		{
			stream->read(&watchedFields[i].val);
			stream->read(&watchedFields[i].prevVal);
		}
	}
}

Maybe that could be your problem...?

#9 Ooh. That's probably a bit of an issue :P. I'll fix that up and see what happens.

EDIT: Seems to be fixed! Thank you for your astute reading :) You are my official hero ;)