How do I learn to make a coremod? (Dun dun dun...)

[SuperGeniusZeb]

See title. Specifically, I want to be able to override just 1 method in BlockPistonStructureHelper... addBlockLine() to be specific. I'm trying to increase the piston push limit from 12 to 16, and having taken a look at the vanilla code, I can see that it's literally a 2-line change to do it. I am well aware that coremodding is by far no easy task (especially for someone with as little experience as myself), and is one of the most complex and hated aspects of modding. But I want to try anyway and hopefully learn something and gain some experience, even if I fail. Where do I start, and also, what are the alternatives to using a coremod? I know Forge replaces vanilla buckets with custom ones, but I'm not sure how I would do something like that and ensure compatiblity with mods requiring pistons in recipes and stuff like that, or how difficult it would be in comparison to coremodding.

[diesieben07]

FML has a substitution mechanic that allows you to substitute registry entries with your own. That is a much better option than coremodding. Basically if you cannot figure out how to make a coremod, you are not the person to make one (not that anyone should ever make one...).

[Draco18s]

what are the alternatives to using a coremod? I know Forge replaces vanilla buckets with custom ones, but I'm not sure how I would do something like that and ensure compatiblity with mods requiring pistons in recipes and stuff like that, or how difficult it would be in comparison to coremodding.

 

Skipping over the "where to start" because don't.  You will not find Forge-specific details on starting to coremod.  There used to be slight hint here and there, but the Forge team is working to make it so that coremodding is not needed at all.  Instead, make a pull request to get the change you want implemented into Forge itself.  I recently did that myself.

 

On to the other question, alternatives:

Block/Item substitution

OreDictionary ("requiring pistons in recipes") or outright modifying the list of recipes to find entries that don't use oredict recipes.

Events - almost everything you'd want to be able to do as a result of coremodding has an event.  If it doesn't:

Make a pull request

[Elix_x]

As Draco said, in almost all cases, you have an alternative. In in the worst case, when events don't exist, registry aliases don't work, you can try finding another way. For example, overriding the class and using reflection to subsitue instances.

 

@Draco

make a pull request to get the change you want implemented into Forge itself.

There's one problem though... Sometimes (*cough* *cough*) it may take a few months before forge either rejects or accepts your PR... Or it may never ever get neither accepted nor rejected...

[Draco18s]

There's one problem though... Sometimes (*cough* *cough*) it may take a few months before forge either rejects or accepts your PR... Or it may never ever get neither accepted nor rejected...

 

As I've found it large comes down to "if it's been a few days, post a comment asking why it's not been accepted."

The entire process is ungodly tedious with several points of failure that it is very easy as a programmer to overlook and which Lex will come along and go "You did X wrong" and then proceed to mark every occurrence with "..." as if you're somehow only barely intelligent.

 

The "how to do this properly" list of guidelines is very sparse and doesn't teach you how to look at the patch file and find these problems on your own.  Took at least four rounds of review before I fully understood how I was supposed to be doing things.

 

Or in one case for me, "rejected because it alters vanilla behavior" which I thought was the whole point (as opposed to "rejected because you should have gone about it in by doing X instead of Y").