Override Lava Bucket

Main.cpp

#include <string>
class TextureUVCoordinateSet;

struct Item {
	void** vtable; // 0
	
	static void initItems();
	static TextureUVCoordinateSet getTextureUVCoordinateSet(const std::string&, int);
	
	static Item* mItems[512];
};

const TextureUVCoordinateSet& _myGetIcon(Item* ptr, int data, int, bool) {
	switch(data) {
	case 1: // Milk
		return Item::getTextureUVCoordinateSet("bucket", 1);
	case 8: // Water
		return Item::getTextureUVCoordinateSet("bucket", 2);
	case 10: // Lava
		return Item::getTextureUVCoordinateSet("coal", 0); // Return a custom texture for lava.
	default: // Empty
		return Item::getTextureUVCoordinateSet("bucket", 0);
	}
}

void (*_Item$initItems)();
void Item$initItems() {
	// Call the real pointer so that all Items will be initialized
	_Item$initItems();
	
	// Get the BucketItem vtable and replace the 45th function (_ZNK4Item7getIconEiib) with our own code.
	Item::mItems[325]->vtable[45] = (void*) &_myGetItem;
}

// Add this into your JNI_OnLoad in your addon.
MSHookFunction((void*) &Item::initItems, (void*) &Item$initItems, (void**) &_Item$initItems);

thanks for the example!