net.minecraft.util.EnumHand#OFF_HAND源码实例Demo

/**
 * Checks if the requested item is currently in the player's hand such that it would be used for using/placing.
 * This means, that it must either be in the main hand, or the main hand must be empty and the item is in the offhand.
 * @param player
 * @param stack
 * @param lenient if true, then NBT tags and also damage of damageable items are ignored
 * @return
 */
@Nullable
public static EnumHand getUsedHandForItem(EntityPlayer player, ItemStack stack, boolean lenient)
{
    EnumHand hand = null;

    if (lenient)
    {
        if (ItemStack.areItemsEqualIgnoreDurability(player.getHeldItemMainhand(), stack))
        {
            hand = EnumHand.MAIN_HAND;
        }
        else if (player.getHeldItemMainhand().isEmpty() && ItemStack.areItemsEqualIgnoreDurability(player.getHeldItemOffhand(), stack))
        {
            hand = EnumHand.OFF_HAND;
        }
    }
    else
    {
        if (InventoryUtils.areStacksEqual(player.getHeldItemMainhand(), stack))
        {
            hand = EnumHand.MAIN_HAND;
        }
        else if (player.getHeldItemMainhand().isEmpty() && InventoryUtils.areStacksEqual(player.getHeldItemOffhand(), stack))
        {
            hand = EnumHand.OFF_HAND;
        }
    }

    return hand;
}
 

private void processEvent(Event event, EnumHand hand, EntityPlayer p, ICyberwareUserData cyberware)
{
	EnumHandSide mainHand = p.getPrimaryHand();
	EnumHandSide offHand = ((mainHand == EnumHandSide.LEFT) ? EnumHandSide.RIGHT : EnumHandSide.LEFT);
	EnumSide correspondingMainHand = ((mainHand == EnumHandSide.RIGHT) ? EnumSide.RIGHT : EnumSide.LEFT);
	EnumSide correspondingOffHand = ((offHand == EnumHandSide.RIGHT) ? EnumSide.RIGHT : EnumSide.LEFT);
	
	boolean leftUnpowered = false;
	ItemStack armLeft = cyberware.getCyberware(new ItemStack(CyberwareContent.cyberlimbs, 1, 0));
	if (armLeft != null && !ItemCyberlimb.isPowered(armLeft))
	{
		leftUnpowered = true;
	}
	
	boolean rightUnpowered = false;
	ItemStack armRight = cyberware.getCyberware(new ItemStack(CyberwareContent.cyberlimbs, 1, 1));
	if (armRight != null && !ItemCyberlimb.isPowered(armRight))
	{
		rightUnpowered = true;
	}

	if (hand == EnumHand.MAIN_HAND && (!cyberware.hasEssential(EnumSlot.ARM, correspondingMainHand) || leftUnpowered))
	{
		event.setCanceled(true);
	}
	else if (hand == EnumHand.OFF_HAND && (!cyberware.hasEssential(EnumSlot.ARM, correspondingOffHand) || rightUnpowered))
	{
		event.setCanceled(true);
	}
}
 

@Nonnull
@Override
public ActionResult<ItemStack> onItemRightClick(@Nonnull ItemStack itemstack, World world, EntityPlayer playerIn, EnumHand hand) {
    FMLLog.info("Book onItemRightClick stack=%s, hand=%s", itemstack, hand);
    // don't activate the GUI if in offhand; don't do *anything*
    if (hand == EnumHand.OFF_HAND) return new ActionResult(EnumActionResult.FAIL, itemstack);

    PyCode.proxy.openBook(playerIn, itemstack);
    return new ActionResult(EnumActionResult.SUCCESS, itemstack);
}
 

/**
 * Sets the held item, without playing the equip sound.
 * @param player
 * @param hand
 * @param stack
 */
public static void setHeldItemWithoutEquipSound(EntityPlayer player, EnumHand hand, ItemStack stack)
{
    if (hand == EnumHand.MAIN_HAND)
    {
        player.inventory.mainInventory.set(player.inventory.currentItem, stack);
    }
    else if (hand == EnumHand.OFF_HAND)
    {
        player.inventory.offHandInventory.set(0, stack);
    }
}
 

@SubscribeEvent
public void onPlayerInteractBlock(PlayerInteractEvent.RightClickBlock event) {

	// This event is fired twice, once for each hand. Unfortunately there
	// is no way to set the result of the main hand interaction to SUCCESS
	// so the off hand one will be skipped. So: Hacky code!

	if (cancelOffHand) {
		cancelOffHand = false;
		if (event.getHand() == EnumHand.OFF_HAND)
			{ event.setCanceled(true); return; }
	}

	// When players sneak-right-click the ground with an
	// empty hand, place down their equipped backpack.

	EntityPlayer player = event.getEntityPlayer();
	World world = event.getWorld();
	if (!player.isSneaking() || (event.getHand() != EnumHand.MAIN_HAND) ||
	    !player.getHeldItem(EnumHand.MAIN_HAND).isEmpty()) return;

	IBackpack backpack = BackpackHelper.getBackpack(player);
	if (backpack == null) return;

	// Try place the equipped backpack on the ground by using it. Also takes
	// care of setting the tile entity stack and data as well as unequipping.
	// See ItemBackpack.onItemUse.
	player.inventory.mainInventory.set(player.inventory.currentItem, backpack.getStack());
	if (backpack.getStack().onItemUse(
			player, world, event.getPos(), EnumHand.MAIN_HAND,
			event.getFace(), 0.5F, 0.5F, 0.5F) == EnumActionResult.SUCCESS) {

		player.swingArm(EnumHand.MAIN_HAND);
		event.setCanceled(true);
		cancelOffHand = true;

	} else player.inventory.mainInventory.set(player.inventory.currentItem, ItemStack.EMPTY);

}
 

@Override
public EnumActionResult onItemUseFirst(EntityPlayer player, World world, BlockPos pos, EnumFacing side, float hitX,
		float hitY, float hitZ, EnumHand hand) {
	Block block = world.getBlockState(pos).getBlock();
	if (player.isSneaking() || hand == EnumHand.OFF_HAND) {
		return EnumActionResult.PASS;
	}
	if (IC2.platform.isRendering()) {
		return EnumActionResult.SUCCESS;
	}
	TileEntity tileEntity = world.getTileEntity(pos);
	if (GTConfig.general.enableMagnifyingGlassGivesEUTooltips && tileEntity instanceof IEnergySink) {
		IEnergySink euSink = (IEnergySink) tileEntity;
		IC2.platform.messagePlayer(player, "Input Tier: " + euSink.getSinkTier());
		IC2.platform.messagePlayer(player, "Input Max: " + EnergyNet.instance.getPowerFromTier(euSink.getSinkTier())
				+ " EU");
	}
	if (tileEntity instanceof IProgressMachine) {
		IProgressMachine progress = (IProgressMachine) tileEntity;
		IC2.platform.messagePlayer(player, "Progress: "
				+ +(Math.round((progress.getProgress() / progress.getMaxProgress()) * 100)) + "%");
	}
	if (tileEntity instanceof IGTMultiTileStatus) {
		IGTMultiTileStatus multi = (IGTMultiTileStatus) tileEntity;
		IC2.platform.messagePlayer(player, "Correct Strucuture: " + multi.getStructureValid());
	}
	if (tileEntity instanceof IGTDebuggableTile) {
		LinkedHashMap<String, Boolean> data = new LinkedHashMap<>();
		IGTDebuggableTile debug = (IGTDebuggableTile) tileEntity;
		debug.getData(data);
		for (Map.Entry<String, Boolean> entry : data.entrySet()) {
			if (!entry.getValue()) {
				IC2.platform.messagePlayer(player, entry.getKey());
			}
		}
	}
	if (GTBedrockOreHandler.isBedrockOre(block)) {
		ItemStack resource = GTBedrockOreHandler.getResource(block);
		String amount = resource.getCount() > 1 ? " x " + resource.getCount() : "";
		IC2.platform.messagePlayer(player, "Contains: " + GTBedrockOreHandler.getResource(block).getDisplayName()
				+ amount);
	}
	world.playSound(null, player.getPosition(), SoundEvents.ENTITY_VILLAGER_AMBIENT, SoundCategory.PLAYERS, 1.0F, 1.0F);
	return EnumActionResult.SUCCESS;
}
 

private void renderItemInFirstPerson(float partialTicks)
{
	ItemRenderer ir = mc.getItemRenderer();
	AbstractClientPlayer abstractclientplayer = mc.thePlayer;
	float f = abstractclientplayer.getSwingProgress(partialTicks);
	EnumHand enumhand = (EnumHand)Objects.firstNonNull(abstractclientplayer.swingingHand, EnumHand.MAIN_HAND);
	float f1 = abstractclientplayer.prevRotationPitch + (abstractclientplayer.rotationPitch - abstractclientplayer.prevRotationPitch) * partialTicks;
	float f2 = abstractclientplayer.prevRotationYaw + (abstractclientplayer.rotationYaw - abstractclientplayer.prevRotationYaw) * partialTicks;
	boolean flag = true;
	boolean flag1 = true;

	if (abstractclientplayer.isHandActive())
	{
		ItemStack itemstack = abstractclientplayer.getActiveItemStack();

		if (itemstack != null && itemstack.getItem() == Items.BOW) //Forge: Data watcher can desync and cause this to NPE...
		{
			EnumHand enumhand1 = abstractclientplayer.getActiveHand();
			flag = enumhand1 == EnumHand.MAIN_HAND;
			flag1 = !flag;
		}
	}

	rotateArroundXAndY(f1, f2);
	setLightmap();
	rotateArm(partialTicks);
	GlStateManager.enableRescaleNormal();

	ItemStack itemStackMainHand = ReflectionHelper.getPrivateValue(ItemRenderer.class, ir, 3);
	ItemStack itemStackOffHand = ReflectionHelper.getPrivateValue(ItemRenderer.class, ir, 4);
	float equippedProgressMainHand = ReflectionHelper.getPrivateValue(ItemRenderer.class, ir, 5);
	float prevEquippedProgressMainHand = ReflectionHelper.getPrivateValue(ItemRenderer.class, ir, 6);
	float equippedProgressOffHand = ReflectionHelper.getPrivateValue(ItemRenderer.class, ir, 7);
	float prevEquippedProgressOffHand = ReflectionHelper.getPrivateValue(ItemRenderer.class, ir, 8);

	RenderCyberlimbHand.INSTANCE.itemStackMainHand = itemStackMainHand;
	RenderCyberlimbHand.INSTANCE.itemStackOffHand = itemStackOffHand;

	if (flag && !missingSecondArm)
	{
		float f3 = enumhand == EnumHand.MAIN_HAND ? f : 0.0F;
		float f5 = 1.0F - (prevEquippedProgressMainHand + (equippedProgressMainHand - prevEquippedProgressMainHand) * partialTicks);
		RenderCyberlimbHand.INSTANCE.leftRobot = hasRoboLeft;
		RenderCyberlimbHand.INSTANCE.rightRobot = hasRoboRight;
		RenderCyberlimbHand.INSTANCE.renderItemInFirstPerson(abstractclientplayer, partialTicks, f1, EnumHand.MAIN_HAND, f3, itemStackMainHand, f5);
	}

	if (flag1 && !missingArm)
	{
		float f4 = enumhand == EnumHand.OFF_HAND ? f : 0.0F;
		float f6 = 1.0F - (prevEquippedProgressOffHand + (equippedProgressOffHand - prevEquippedProgressOffHand) * partialTicks);
		RenderCyberlimbHand.INSTANCE.leftRobot = hasRoboLeft;
		RenderCyberlimbHand.INSTANCE.rightRobot = hasRoboRight;
		RenderCyberlimbHand.INSTANCE.renderItemInFirstPerson(abstractclientplayer, partialTicks, f1, EnumHand.OFF_HAND, f4, itemStackOffHand, f6);
	}

	GlStateManager.disableRescaleNormal();
	RenderHelper.disableStandardItemLighting();
}
 

public void doRenderLayer(EntityLivingBase entity, float limbSwing, float limbSwingAmount,
                          float partialTicks, float ageInTicks, float netHeadYaw, float headPitch, float scale) {
	
	IBackpack backpack;
	RenderOptions renderOptions;
	if (_overrideBackpack != null) {
		backpack = _overrideBackpack;
		renderOptions = _overrideRenderOptions;
	} else {
		backpack = BackpackHelper.getBackpack(entity);
		BackpackEntityEntry entry = BackpackRegistry.getEntityEntry(entity.getClass());
		renderOptions = (entry != null) ? entry.renderOptions : null;
	}
	if ((backpack == null) || (renderOptions == null)) return;
	
	GlStateManager.pushMatrix();
	
	if (entity.isChild()) {
		GlStateManager.scale(0.5F, 0.5F, 0.5F);
		GlStateManager.translate(0.0F, 24.0F * scale, 0.0F);
	}
	
	ModelBase modelBase = this.livingEntityRenderer.getMainModel();
	if (modelBase instanceof ModelBiped) {
		ModelRenderer bipedBody = ((ModelBiped) modelBase).bipedBody;
		
		if (entity.isSneaking()) {
			// FIXME: Can be sneaking while flying with the elytra, then backpack is misaligned..?
			GlStateManager.translate(0.0F, 0.2F, 0.0F);
		}
		
		bipedBody.postRender(scale);
	} else {
		// Fallback to the custom way of transforming the backpack.
		// Make backpack swing with body as players swing their arms.
		float swingProgress = entity.getSwingProgress(partialTicks);
		float swingAngle = MathHelper.sin(MathHelper.sqrt(swingProgress) * ((float)Math.PI * 2.0F)) * 0.2F;
		if ((entity.swingingHand == EnumHand.OFF_HAND) ^
		    (entity.getPrimaryHand() == EnumHandSide.LEFT)) swingAngle *= -1;
		if (swingAngle != 0) GlStateManager.rotate((float)Math.toDegrees(swingAngle), 0.0F, 1.0F, 0.0F);
		
		// Rotate backpack if entity is sneaking.
		if (entity.isSneaking()) {
			// FIXME: Can be sneaking while flying with the elytra, then backpack is misaligned..?
			GlStateManager.translate(0.0F, 0.2F, 0.0F);
			GlStateManager.rotate(90.0F / (float)Math.PI, 1.0F, 0.0F, 0.0F);
		}
	}
	
	GlStateManager.scale(renderOptions.scale, renderOptions.scale, renderOptions.scale);
	GlStateManager.translate(8.0F * scale, renderOptions.y * scale, renderOptions.z * scale);
	GlStateManager.rotate(180.0F, 0.0F, 0.0F, 1.0F);
	GlStateManager.rotate((float)renderOptions.rotate, 1.0F, 0.0F, 0.0F);
	GlStateManager.translate(0, ProxyClient.MODEL_BACKPACK_BOX.maxY * scale * -16,
	                            ProxyClient.MODEL_BACKPACK_BOX.minZ * scale * -16);
	
	renderBackpack(backpack, entity.ticksExisted + partialTicks, false);
	
	GlStateManager.popMatrix();
	
}