ASM Bytecode issues

Just having a little trouble catching up to forge 1.7.2 and gradle. I'm trying to change a few things using Bytecode but can't seem to figure how to do it. There are no sources to edit, and I've found no help on the web showing how to do this. I just want to change a few things in the base files, which are, as far as I know, impossible to change using events or something. Are there any tutorials out there which shows how to patch base files with the new gradle stuff? If not, can someone please explain how to do this?

Thanks in advance.

What are you trying to change?

What are you trying to change?

Well, a few things, like remove hunger, changin armor mechanics, changing damaging mechanics and stuff like that.

You will need to be more specific, a lot of that can be done without base edits.

You will need to be more specific, a lot of that can be done without base edits.

Well sure. Let's take the armor as an example. I want to remove the old, ugly, vanilla armor mechanic. I don't like it at all, it's messy. Instead of the original armor I want to create damage reduction out from armor points. Let's say you have 1000 armor, that will equal, let's say 40% damage reduction. To do this, I would have made this:

    /**
     * Reduces damage, depending on armor
     */
    protected float applyArmorCalculations(DamageSource par1DamageSource, float par2)
    {
        if (!par1DamageSource.isUnblockable())
        {
            int i = 25 - this.getTotalArmorValue();
            float f1 = par2 * (float)i;
            this.damageArmor(par2);
            par2 = f1 / 25.0F;
        }

        return par2;
    }

into this:

    /**
     * Reduces damage, depending on armor
     */
    protected float applyArmorCalculations(DamageSource par1DamageSource, float par2)
    {
        if (!par1DamageSource.isUnblockable())
        {
            par2 = ArmorHelper.damageReduction();
        }

        return par2;
    }

or something like that. ArmorHelper.damageReduction(); would return a value of 0.6.

I guess that's as specific as I can get. This is what I did back in 1.6, using class transformers, but it seems a lot harder now that the source code is non-editable.

You can use the LivingHurtEvent to deal with that which is fired in the only two places that that function is invoked from.

You can use the LivingHurtEvent to deal with that which is fired in the only two places that that function is invoked from.

Hmm, maybe you're right. It seems like I can do a few more things using events. But there are more things, like, I would need to add a little if statement in the left click void in Minecraft.class. I'm gonna do so that you cannot swing your arm as long as it's already swinging. I'm not gonna ask you to do all the work on my mod or anything, but I just don't think there are events for everything so I'm just asking if there is any solution.

Short answer, No, if you are editing base classes in ANY WAY you're doing it wrong and you're better off asking for help and looking for more information from people who know more/have more experience then you.

Short answer, No, if you are editing base classes in ANY WAY you're doing it wrong and you're better off asking for help and looking for more information from people who know more/have more experience then you.

But since there are a couple of things that isn't supported by events and stuff, I'm thinking, if I add a small if-statement or something in a field, it won't matter too much. Maybe it can cause minor non-compability with a few mods, but this mod isn't supposed to be played with anything else than maybe TMI, graphic mods, x-ray and other non-gamechanging mods. And if I change as little as I'm going to, I'm pretty sure it won't affect these mods in any way. I'm doing what I can not to edit base classes, but there are still 2-3 small statements I'm missing.

Coremods exist for a reason, However, I restate my point.

If you are editing base classes you are doing it WRONG.

It is better to speak up and get help and MOST LIKELY as with the cases above someone can point you in a better direction then CoreModding/BaseEdits.

Anyone who writes a core mod needs to get into the mindset that they are doing it WRONG and should ALWAYS seek a better solution if they can.

There will be times where legitimatly you can not do something in Forge {its getting increasingly rare}

Thats why the coremod system exists. HOWEVER. It should always be a LAST RESORT. And you should always try to STOP using coremods.

Think of it this way, If you saw, in one of my patches I accedently typed < when I mean to have <=

Would you silently coremod that comparison to fix it and move on your merry way?

Or would just file a issue on the git informing me I had made a mistake and have me fix it?

Think of the ENTIRE minecraft code base as Forge's domain. If you want to make ANY edit to it, if there are ANY bugs, etc.. File a issue on git and we'll address it.

Not saying everything you do will get into Forge, because, not being a dick here, but I would probably see and understand a lot more of the implications of changes then you would simply due to my experiance in MC code itself.

But if it's a good issue and we work back and forth to make it acceptable, then it'll get pulled.

Coremods exist for a reason, However, I restate my point.

If you are editing base classes you are doing it WRONG.

It is better to speak up and get help and MOST LIKELY as with the cases above someone can point you in a better direction then CoreModding/BaseEdits.

Anyone who writes a core mod needs to get into the mindset that they are doing it WRONG and should ALWAYS seek a better solution if they can.

 

 

There will be times where legitimatly you can not do something in Forge {its getting increasingly rare}

Thats why the coremod system exists. HOWEVER. It should always be a LAST RESORT. And you should always try to STOP using coremods.

 

Think of it this way, If you saw, in one of my patches I accedently typed < when I mean to have <=

Would you silently coremod that comparison to fix it and move on your merry way?

Or would just file a issue on the git informing me I had made a mistake and have me fix it?

Think of the ENTIRE minecraft code base as Forge's domain. If you want to make ANY edit to it, if there are ANY bugs, etc.. File a issue on git and we'll address it.

Not saying everything you do will get into Forge, because, not being a dick here, but I would probably see and understand a lot more of the implications of changes then you would simply due to my experiance in MC code itself.

But if it's a good issue and we work back and forth to make it acceptable, then it'll get pulled.

Allright. Thanks. I'll try to do whatever I can not to use coremods. It seems like I've finished most of the mechanics anyways. If you want, you can help me with it. I don't think there are any events to help me with this, so I have to do something else. I'm not expecting you to finish the code, but if you would tell me where to look, I'd be grateful. First thing I'm gonna do is to add a few more slots to the survival inventory. I've already added the slots, and it looks great, but the problem is that when I click the slot, I get a crash.

java.lang.IndexOutOfBoundsException: Index: 45, Size: 45
at java.util.ArrayList.RangeCheck(ArrayList.java:547)
at java.util.ArrayList.get(ArrayList.java:322)
at net.minecraft.inventory.Container.slotClick(Container.java:302)
at net.minecraft.network.NetHandlerPlayServer.processClickWindow(NetHandlerPlayServer.java:948)
at net.minecraft.network.play.client.C0EPacketClickWindow.processPacket(C0EPacketClickWindow.java:41)
at net.minecraft.network.play.client.C0EPacketClickWindow.processPacket(C0EPacketClickWindow.java:113)
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:232)
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:182)
at net.minecraft.server.MinecraftServer.updateTimeLightAndEntities(MinecraftServer.java:720)
at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:608)
at net.minecraft.server.integrated.IntegratedServer.tick(IntegratedServer.java:118)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:482)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:746)

Not quite sure why this is happening, as I am putting the slot into the arraylist.

I'll show you my code.

WMod:

    public static void addSlotToContainer(Slot par1Slot, Container container)
    {
        par1Slot.slotNumber = container.inventorySlots.size();
        container.inventorySlots.add(par1Slot);
        container.inventoryItemStacks.add((Object)null);
    }

ContainerEvent:

		ItemStack[] itemStack = new ItemStack[8];
		for(int i = 0; i < 4; i++)
		{
			itemStack[i] = mc.thePlayer.inventory.armorInventory[i];
		}
		mc.thePlayer.inventory.armorInventory = itemStack;
		for(int i = 0; i < 4; i++)
		{
			final int k = i;
			Slot slot = (new Slot(mc.thePlayer.inventory, 43 - k, -10, 8 + i * 18)
			{
				private static final String __OBFID = "CL_00001755";
				/**
				 * Returns the maximum stack size for a given slot (usually the same as getInventoryStackLimit(), but 1
				 * in the case of armor slots)
				 */
				public int getSlotStackLimit()
				{
					return 1;
				}
				/**
				 * Check if the stack is a valid item for this slot. Always true beside for the armor slots.
				 */
				public boolean isItemValid(ItemStack par1ItemStack)
				{
					if (par1ItemStack == null) return false;
					return par1ItemStack.getItem().isValidArmor(par1ItemStack, k + 4, mc.thePlayer);
				}
				/**
				 * Returns the icon index on items.png that is used as background image of the slot.
				 */
				@SideOnly(Side.CLIENT)
				public IIcon getBackgroundIconIndex()
				{
					return WItemArmor.getIconForSlot(k + 4);
				}
			});
			WMod.addSlotToContainer(slot, mc.thePlayer.inventoryContainer);
		}

private static final String __OBFID = "CL_00001755";

Why do you have that line?

And there should be a Intentory Open event that you cal use to add these slots with.

However, adding slots to the inventory is a bit.. bad because it can cause conflcits with other mods that add slots.

A workaround for additional survival inventory slots is to use IExtendedEntityProperties to add them, with an accompanying GUI / Container, etc., and bind a key to open your custom inventory; players can re-map the key to 'E' if they want, effectively making your inventory the new 'vanilla inventory'. This circumvents both the issue of inter-mod compatibility and having to manipulate byte-code; it's easy and clean, imo.

If you want to see an example / tutorial on it, check here.

private static final String __OBFID = "CL_00001755";

Why do you have that line?

And there should be a Intentory Open event that you cal use to add these slots with.

However, adding slots to the inventory is a bit.. bad because it can cause conflcits with other mods that add slots.

A workaround for additional survival inventory slots is to use IExtendedEntityProperties to add them, with an accompanying GUI / Container, etc., and bind a key to open your custom inventory; players can re-map the key to 'E' if they want, effectively making your inventory the new 'vanilla inventory'. This circumvents both the issue of inter-mod compatibility and having to manipulate byte-code; it's easy and clean, imo.

 

If you want to see an example / tutorial on it, check here.

I played a little around with the inventory this night. My internet wasn't working so I had to find out of this myself. The code I used above, the addSlotContainer worked, but I forgot to add slots both in the client and the server. That's what caused the error. And I'm fine with the incompability, because playing my mod with any inventory changing mods will ruin the gameplay. Oh, and the "private static final String __OBFID = "CL_00001755";" is something that's already in the armor slot code, so I just kept it. Didn't think much of it.

Anyways, there is one last thing I need help with. It's the swinging animation. I want to change how fast your hand swings according to the item you're holding. I've tried so many different things, but it's really hard to figure a way to do this. I've somehow tried to overlap the old "this.swingProgress = (float)this.swingProgressInt / (float)i;", but it seems so cause bugs no matter how I do it. What I need is something like

this.swingProgress = (float)this.swingProgressInt / (float)i / j;

where "j" is the item speed. I'm guessing there should be a simple way to do this, maybe by cancel out the "updateArmSwingProgress()" which takes care of the swing speed. I've looked for a way to cancel it, but couldn't find an easy and non-buggy way.

What you want for the swing speed could be emulated by using the dig slowdown potion effect.

As for the __OBFID, this is a reason you should UNDERSTAND things before you copy/paste code -.-

This is For VANILLA classes only.

If you have __OBFID in your code you could break shit. {We've fixed most cases, but hey people break things}