Incompatibility with LibGui

Question

Incompatibility with LibGui

CofiPRT opened this issue a year ago · 0 comments

CofiPRT commented a year ago

I was investigating an issue where using LibGui (or any mod that includes it) together with OptiFabric leads to a game crash on startup.
OptiFabric version: 1.13.24
Fabric API version: 0.80.0+1.19.4
LibGui versions: 7.0.1+1.19.4, 7.1.0+1.19.4, 7.1.1+1.19.4

This is what the stack trace look like

Caused by: java.lang.NullPointerException: Cannot invoke "String.indexOf(int)" because "resourceName" is null
	at net.minecraft.class_2960.method_12830(class_2960.java:88) ~[client-intermediary.jar:?]
	at net.minecraft.class_2960.<init>(class_2960.java:51) ~[client-intermediary.jar:?]
	at net.fabricmc.fabric.impl.client.rendering.FabricShaderProgram.rewriteAsId(FabricShaderProgram.java:42) ~[fabric-rendering-v1-2.1.2+504944c8f4-d3f123cd32cf48f7.jar:?]
>	at net.minecraft.class_5944.modify$zng000$fabric-rendering-v1$modifyProgramId(class_5944.java:654) ~[client-intermediary.jar:?]
>	at net.minecraft.class_5944.localvar$bfj000$optifabric$modifyProgramID(class_5944.java:1634) ~[client-intermediary.jar:?]
	at net.minecraft.class_5944.<init>(class_5944.java:114) ~[client-intermediary.jar:?]
	at net.minecraft.class_5944.<init>(class_5944.java:108) ~[client-intermediary.jar:?]
	at net.fabricmc.fabric.impl.client.rendering.FabricShaderProgram.<init>(FabricShaderProgram.java:28) ~[fabric-rendering-v1-2.1.2+504944c8f4-d3f123cd32cf48f7.jar:?]
	at net.minecraft.class_757.md001ae3$fabric-rendering-v1$lambda$registerShaders$0$0(class_757.java:2627) ~[client-intermediary.jar:?]
	at io.github.cottonmc.cotton.gui.impl.client.LibGuiShaders.lambda$register$1(LibGuiShaders.java:18) ~[libgui-7.0.1+1.19.4-38026f7114167cd3.jar:?]
	at net.fabricmc.fabric.api.client.rendering.v1.CoreShaderRegistrationCallback.lambda$static$0(CoreShaderRegistrationCallback.java:44) ~[fabric-rendering-v1-2.1.2+504944c8f4-d3f123cd32cf48f7.jar:?]
	at net.minecraft.class_757.handler$zne000$fabric-rendering-v1$registerShaders(class_757.java:2630) ~[client-intermediary.jar:?]
	at net.minecraft.class_757.method_34538(class_757.java:536) ~[client-intermediary.jar:?]
	at net.minecraft.class_757$1.method_45777(class_757.java:460) ~[client-intermediary.jar:?]
	at net.minecraft.class_757$1.method_18788(class_757.java:432) ~[client-intermediary.jar:?]
	at net.minecraft.class_4080.method_18790(class_4080.java:13) ~[client-intermediary.jar:?]
	at java.util.concurrent.CompletableFuture$UniAccept.tryFire(CompletableFuture.java:718) ~[?:?]
	... 20 more

I have marked some interesting methods with > above.

I notice that OptiFabric is making use of ShaderProgramMixin over here.
It is using a method from the Fabric API. Notice the usage of the FabricShaderProgram::rewriteAsId method. If we follow the flow from this point onward, I would deduce that the name field in the previous link ends up being null, for reasons I didn't yet manage to understand, and this is the cause of the exception.

The flow prior to this seems to be the following:

LibGui wants to register a new shader, so this registerShaders injection gets called, where a new instance of FabricShaderProgram is created.
class_5944 is, supposedly, the ShaderProgram class but here's where I start to get a bit lost because I don't understand why there are two calls to its constructor in the stack trace

	at net.minecraft.class_5944.<init>(class_5944.java:114) ~[client-intermediary.jar:?]
	at net.minecraft.class_5944.<init>(class_5944.java:108) ~[client-intermediary.jar:?]

I would guess there are two different constructors, but in the sources that I'm checking I can only see one constructor

Then, according to the stack trace, the OptiFabric mixin gets triggered, and I am confused again because I don't see a call to Identifier::getNamespace in the sources that I'm checking. I don't quite understand the type of interception that happens, but my guess is that: this Fabric Mixin gets triggered inside ShaderProgram's constructor, and with that, it is intercepted by OptiFabric

And of course, after this interception happens, the flow continues and it happens that Fabric's ShaderProgramMixin::name field ends up null, and provoking the crash.

I am presenting this analysis because I don't know how to continue it in order to work toward a fix, and at the same time I want to add a somewhat off-topic question:
Based on OptiFabric's README.md, what should the dependency look like in order to make use of, let's say, the 1.13.24 version of OptiFabric?

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