Check OptiFine Shader at real time

[MCTian-mi]

What

At the moment the Mods#Optifine checks whether shaderpack is active by reflection, the result is cached and never changed afterward.

GregTech/src/main/java/gregtech/api/util/Mods.java

Lines 82 to 99 in 3fc7f42

	// Special Optifine handler, but consolidated here for simplicity
	Optifine(null) {
	@Override
	public boolean isModLoaded() {
	if (this.modLoaded == null) {
	try {
	Class<?> c = Class.forName("net.optifine.shaders.Shaders");
	Field f = c.getDeclaredField("shaderPackLoaded");
	f.setAccessible(true);
	this.modLoaded = f.getBoolean(null);
	} catch (Exception ignored) {
	this.modLoaded = false;
	}
	}
	return this.modLoaded;
	}
	};

This results in issues when players turn shaders on/off after the cache is created. In the case where players disabled shaders, the bloom effect won't come back (since they still think the shader is on from the cached value); and in the other case where the shader is turned off afterward, the game will come to a crash.

This PR make it so the shaderpack load state is checked at real-time, which should potentially fix the issues mentioned above.

Implementation Details

This PR moves the shaderpack checker to a separate enum constant, named ShadersMod (Where the OptiFine shader code originally come from), and @Overrides the isModLoaded method with a reference to Shaders#shaderPackLoaded

ShadersMod(null) {

    @Override
    public boolean isModLoaded() {
        // Check shader pack state at real time instead of caching it
        return OptiFine.isModLoaded() && Shaders.shaderPackLoaded;
    }
}

Where the class net.optifine.shaders.Shaders created in api package is adapted and minimized from OptiFine itself. The OptiFine.isModLoaded() method call serves as a guard to avoid ClassNotFoundExceptions.

And the original enum constant is renamed from Optifine to OptiFine, under the consideration of both fixing the spelling mistake and preventing unexpected compatibility issues. The OptiFine checker is now delegating the forge-provided method for checking OptiFine's existence.

OptiFine(null) {

    @Override
    public boolean isModLoaded() {
       if (this.modLoaded == null) {
            this.modLoaded = FMLCommonHandler.instance().getSide().isClient() &&
                    FMLClientHandler.instance().hasOptifine();
        }
        return this.modLoaded;
    }
}

Outcome

• Above-mentioned issues should (hopefully) get fixed. (Note: Now when you turn shaders on afterward, the game won't crash. Instead, it results in some rendering issues, whose behavior depends on the shader pack you choose. I'm still investigating this issue. But I think it shouldn't be a blocker for this PR.)
• Addons with direct reference to Mods#Optifine will break.

[brachy84]

nice