Better support for reading models and saving to .rbxmx files

[fredgig]

It seems like rbxmk doesn't currently do a great job at saving models to .rbxmx files. Attempting to import into Roblox Studio a .rbxmx generated by rbxmk will be unsuccessful.

I don't know if this is a known issue due to technical limitations, but here is how I am able to fix a corrupted .rbxmx file, even for somewhat complex models.

1. For tags containing an asset URL, wrap the url inside a tag:

BEFORE:

<string name="PROPERTY">rbxassetid://ASSET_ID</string>

AFTER:

<string name="PROPERTY"><url>rbxassetid://ASSET_ID</url></string>

2. Enter the appropriate value inside the ModelMeshData. Not sure how this is found programmatically, but I get it from a .rbxmx file that was directly exported from Roblox Studio.

BEFORE:

<SharedString name="ModelMeshData"></SharedString>

AFTER:

<SharedString name="ModelMeshData">**MODEL_MESH_DATA_STRING**</SharedString>

3. PhysicalConfigData does not seem to contain a valid value. In the same manner as the previous fix for ModelMeshData, I get the tag value from a .rbxmx exported from Studio.

BEFORE:

<SharedString name="PhysicalConfigData"><![CDATA[**SOME_CDATA_STRING**]]></SharedString>

AFTER:

<SharedString name="PhysicalConfigData">**PHYSICAL_CONFIG_DATA_STRING**</SharedString>

4. Finally, at the bottom of the .rbxmx file, add a new set of tags to reference to MODEL_MESH_DATA_STRING, PHYSICAL_CONFIG_DATA_STRING and SOME_CDATA_STRING.

<SharedStrings>	
	<SharedString md5="**MODEL_MESH_DATA_STRING**"></SharedString>	
	<SharedString md5="**PHYSICAL_CONFIG_DATA_STRING**">**SOME_CDATA_STRING**</SharedString>	
</SharedStrings>

[Anaminus]

For properties that should have the Content type, make sure you wrap the value in a Content exprim:

decal.Texture = types.Content("rbxassetid://ASSET_ID")

Alternatively, having a descriptor specified will do this conversion automatically. The easiest way is to include one of the descriptor flags when running a script:

# Download the latest API dump and use as rbxmk.globalDesc
rbxmk run --desc-latest script.lua

As for the SharedString type, this seems to be a problem with rbxfile, which I'll look into.

[Anaminus]

SharedStrings should be fixed, and will be available in the next release.

[fredgig]

For properties that should have the Content type, make sure you wrap the value in a Content exprim:

decal.Texture = types.Content("rbxassetid://ASSET_ID")

Alternatively, having a descriptor specified will do this conversion automatically. The easiest way is to include one of the descriptor flags when running a script:

Looking back at this, I don't think this was fully relevant to my issue, which I failed to put into context.

The issue arises when reading models/instances from a .rbxl file and exporting each individual model/instance as a .rbxml file. Am I wrong to think that I should not have to do actions like wrapping values? Should I still use descriptors for this?

[Anaminus]

This is a known issue. rbxl stores all string-like values as strings, so a descriptor is required to convert these values back to their expected types.

However, even with a descriptor specified, it still wont work. The problem is that the rbx formats do not use descriptors when decoding or encoding types. My plan to fix this is to add a "Desc" option to each rbx format that allows a descriptor to be specified. Additionally, they will fall back to globalDesc if needed.

But yes, a descriptor will always be required to properly convert rbxl to rbxlx, because rbxl does not include information for certain types. I'll make a separate issue to track the progress of descriptors for the rbx formats.

[fredgig]

Got it, I'll keep an eye out for an update. Thanks again.

[Anaminus]

So bb154a5 makes changes to do a lot more to handle value conversions. For example, if the descriptor says a property is of the Content type, then any string-like value will be converted to Content. I also added the DescMode format option to determine the strictness of these conversions.

There is still a caveat, which is that Roblox's API dumps do not include certain serialized properties. I've already anticipated this problem with a system that allows patching of descriptor files. This makes it easy to download the latest API dump and then apply a locally maintained patch.

For example, I have this patch file saved as dump.desc-patch.json:

[
	{
		"Type": 1,
		"Element": "Property",
		"Primary": "Instance",
		"Secondary": "AttributesSerialize",
		"Fields": {
			"CanLoad": true,
			"CanSave": true,
			"Category": "Data",
			"Name": "AttributesSerialize",
			"ReadSecurity": "None",
			"Tags": [
				"NotScriptable"
			],
			"ValueType": {
				"Category": "DataType",
				"Name": "BinaryString"
			},
			"WriteSecurity": "None"
		}
	},
	{
		"Type": 1,
		"Element": "Property",
		"Primary": "Instance",
		"Secondary": "Tags",
		"Fields": {
			"CanLoad": true,
			"CanSave": true,
			"Category": "Data",
			"Name": "Tags",
			"ReadSecurity": "None",
			"Tags": [
				"NotScriptable"
			],
			"ValueType": {
				"Category": "DataType",
				"Name": "BinaryString"
			},
			"WriteSecurity": "None"
		}
	}
]

The command to download the latest dump and apply this patch might look like this:

rbxmk --desc-latest --desc-patch dump.desc-patch.json script.lua

Or, patching it dynamically from within the script could be done like this:

rbxmk.patchDesc(rbxmk.globalDesc, fs.read("dump.desc-patch.json"))

[fredgig]

I will mess around with this in the coming days and let you know how it goes.