Remember that Castagne can be run independantly? It handles all the gameplay on its own, but needs to be hosted by another engine to actually poll input or display anything, which in most cases is Godot. This also means that some data has to be shared, which is the subject of today’s update!
Introducing two new types of data structure to Castagne: ModStructs and HostStructs. ModStructs are an extension of the structures that already exist, they store another Memory Stack and thus can be rolled back if needed. They are separate from the main memory, and live inside of the engine itself, which allows additional abilities where needed.
Currently, this covers the AttackData structure, and you can guess what it’s used for based on the name. The interesting part of ModStructs is that they are also accessible from CASP directly. As such, AttackParam is a thing of the past, you can now directly use Set(Attack.Damage, 1000) for example. It’s also much more flexible than before, as you will be able to declare any type of attack parameter using the declare variable syntax: declare Attack.MyCoolParameter vec() = [0,0,0] creates a new MyCoolParameter attack parameter of type vector. This will still be compatible with the Attack Overrides system, so it’s quite strong!
HostStructs are an extension of ModStructs, as they are one ModStruct plus an additional data structure on the host side. The most direct application is the ModelData structure, which holds the parameters for the model. This is stronger than before on the Castagne side, as you can do Model.Position for example instead of having the whole ModelMove functions. On the host engine side, HostStructs recieve callbacks at key points in the process, such as the graphics update step for models, which are used to handle data while keeping rollback in mind. Since HostStructs have access to this managed memory stack, they can read the correct values and update accordingly, which works better if you use an immediate update structure (meaning, you are not dependant on previous state). The responsability of data lifecycle during rollback will mostly be handled by Castagne, while the responsability of acting on the data is on the HostStruct. This effectively replaces the InstanceData system, which worked in a similar way but was less structured.
Anyway, that’s mostly internal stuff which is going to be useful for engine devs or those that go really far. On your end, it’s most likely buisiness as usual, as you just make your Godot scene and it gets loaded as expected. Or, you use Sprites which are handled for you.
One change that will be coming however as a result is the fusion of the 2.5D fighter and 2D fighter genre into one. This was a big mark of using Godot specifically, and it brought a lot of issues because Godot’s pure 2D engine doesn’t handle 3D models (duh), and as such a lot of default behavior couldn’t be used. Using Godot’s 2D engine won’t be off the table however, as it will become a config option, that way if you want to use pure 2D sprites and background you will be able to set it up.
This change will make the beginner experience much less brittle, and will cause less confusion around some features of the engine which are not available when using the pure 2D renderer as it will be opt-in AFTER the initial approach and ensure you actually know what you’re getting into. Many people think “2D Fighter” refered only to the characters, which is not the case but it’s not something you can “fix”, especially in the first 3 minutes someone has with Castagne. It also prevented the default characters from being used, so the choice most beginners made would cut them off from learning! Won’t happen as much now.
