BackpackDisplay

Adds a tooltip to show what's in your backpack, shulker box or other container item.
Configurable of how to get contents for the container item.
The mod has out-of-the-box support for vanilla shulker boxes, storage drawers drawers, and forestry backpacks. You can add support to more items by writing custom rules in the mod's config.

Configurable options(See the mod's config):

• The items that the mod's tooltip should be shown for
• Position and color of the tooltip
• Optional hold or release a keybind to show the tooltip

Config Format

displayRules is the main config of the mod. It lets you to add new container items to display the backpack tooltip, with the following format:
Format: <modID>:<itemID>[:meta]#<rule type>#<rule definition>

meta is a comma-separated list for meta-values to match.
For example,1,2,5-8 allows tooltip to show on the item with metadata 1,2,5,6,7,8.
When meta is absent, tooltip to show on the item ignoring meta.

Rule definition is according to the rule type selected.

Paths

Path is commonly used in the rules, and have a format like path.to.the.item.
For example, in this NBT structure:

{"list":[{"key1":"value"},{"key2":"item"}]}

The path list.1.key2 will get the tag "item" from it.

List rule

Rule type: list

In this rule, items are all under a NBTTagList or a NBTTagCompound.

Rule definition:path.to.the.list[;path.to.the.itemstack[;path.to.the.counts]]
The last 2 paths is relative to the tag item in the list. If the counts is absent, the count in the itemstack is used instead.

Example: Show contents when hovering a purple shulker box

minecraft:purple_shulker_box#list#BlockEntityTag.Items

Single rule

Rule type: single

In this rule, an item is under a fixed path, with an optional external count value.

Rule definition:path.to.the.itemstack[;path.to.the.counts[;calculations for the counts]]
If the counts is absent, the count in the itemstack is used instead.

Example: Show content for every basic drawers in storage drawers mod

storagedrawers:basicdrawers:0#single#BlockEntityTag.Drawers.0.Item;BlockEntityTag.Drawers.0.Count
storagedrawers:basicdrawers:1,3#single#BlockEntityTag.Drawers.0.Item;BlockEntityTag.Drawers.0.Count
storagedrawers:basicdrawers:1,3#single#BlockEntityTag.Drawers.1.Item;BlockEntityTag.Drawers.1.Count
storagedrawers:basicdrawers:2,4#single#BlockEntityTag.Drawers.0.Item;BlockEntityTag.Drawers.0.Count
storagedrawers:basicdrawers:2,4#single#BlockEntityTag.Drawers.1.Item;BlockEntityTag.Drawers.1.Count
storagedrawers:basicdrawers:2,4#single#BlockEntityTag.Drawers.2.Item;BlockEntityTag.Drawers.2.Count
storagedrawers:basicdrawers:2,4#single#BlockEntityTag.Drawers.3.Item;BlockEntityTag.Drawers.3.Count

This rule supports further calculation to get the real item count if it's not in the tag directly but can be calculated from the values in the tag.
Calculations are a string starting with a operator in +-*/^% and followed by a path. The order of calculation is like that on a basic calculator that cannot input expressions.
All calculations is done in integer.

Example: Show content for compact drawers in storage drawers mod

storagedrawers:compdrawers#single#BlockEntityTag.Drawers.Items.0.Item;BlockEntityTag.Drawers.Count;/BlockEntityTag.Drawers.Items.0.Conv
storagedrawers:compdrawers#single#BlockEntityTag.Drawers.Items.1.Item;BlockEntityTag.Drawers.Count;/BlockEntityTag.Drawers.Items.1.Conv
storagedrawers:compdrawers#single#BlockEntityTag.Drawers.Items.2.Item;BlockEntityTag.Drawers.Count;/BlockEntityTag.Drawers.Items.2.Conv

Crafttweaker Support

Starting from v1.3, crafttweaker is supported to add custom functions to get what items to display.
It's suggested to only write entries in a script with #sideonly client Preprocessor. Otherwise it will cause errors on dedicated server, because this mod is client only.
import mods.backpackdisplay.BackpackDisplay; // IIngredient to match items to add the tooltip, function to return an array of items from a given itemstack BackpackDisplay.addBackDisplay( IIngredient, (IItemStack) -> IItemStack[] );

Example: show a crafting table and the crafting result for every wood log in <ore:logWood>

#sideonly client    
import mods.backpackdisplay.BackpackDisplay;
import crafttweaker.item.IItemStack;
BackpackDisplay.addBackDisplay(<ore:logWood>,function(item){
    var items = [<minecraft:crafting_table>,recipes.craft([[item]])] as IItemStack[];
    return items;
});

With both crafttweaker rules and normal rules present on an item, items from crafttweaker support will appear before items from normal rules.