ItemStacks

_data/links.yml

@@ -53,8 +53,14 @@
 
 - hr: true
 
-- title: Releasing a Mod
+- title: ItemStacks
   num:   12
+  link:  chapters/itemstacks.html
+
+- hr: true
+
+- title: Releasing a Mod
+  num: 13
   link: chapters/releasing.html
 
 - hr: true

chapters/itemstacks.md

@@ -0,0 +1,112 @@
+---
+title: ItemStack
+layout: default
+root: ../
+---
+
+## Introduction
+
+In this chapter you will learn how to use ItemStacks.
+
+* Creating ItemStacks
+* Name and Count
+* Wear
+* Copying a stack
+* Lua Tables
+* Metadata
+* More Methods
+
+## Creating ItemStacks
+
+An item stack is a... stack of items. It's basically just an item type with
+a count of items in the stack.
+
+You can create a stack like so:
+
+{% highlight lua %}
+local items = ItemStack("default:dirt")
+local items = ItemStack("default:stone 99")
+{% endhighlight %}
+
+You could alternatively create a blank ItemStack and fill it using methods:
+
+{% highlight lua %}
+local items = ItemStack()
+if items:set_name("default:dirt") then
+	items:set_count(99)
+else
+	print("An error occured!")
+end
+{% endhighlight %}
+
+## Name and Count
+
+{% highlight lua %}
+local items = ItemStack("default:stone")
+print(items:get_name()) -- default:stone
+print(items:get_count()) -- 1
+
+items:set_count(99)
+print(items:get_name()) -- default:stone
+print(items:get_count()) -- 99
+
+if items:set_name("default:dirt") then
+	print(items:get_name()) -- default:dirt
+	print(items:get_count()) -- 99
+else
+	error("This shouldn't happen")
+end
+{% endhighlight %}
+
+## Wear
+
+ItemStacks also have wear on them. Wear is a number out of 65535, the higher is
+more warn.
+
+You use `add_wear()`, `get_wear()` and `set_wear(wear)`.
+
+{% highlight lua %}
+local items = ItemStack("default:dirt")
+local max_uses = 10
+
+-- This is done automatically when you use a tool that digs things
+-- It increases the wear of an item by one use.
+items:add_wear(65535 / (max_uses - 1))
+{% endhighlight %}
+
+When digging a node, the amount of wear a tool gets may depends on the node
+being dug. So max_uses varies depending on what is being dug.
+
+## Copying a stack
+
+It's as simple as this:
+
+{% highlight lua %}
+local items2 = ItemStack(items)
+{% endhighlight %}
+
+## Lua Tables
+
+{% highlight lua %}
+local data = items:to_table()
+local items2 = ItemStack(data)
+{% endhighlight %}
+
+## Metadata
+
+ItemStacks can also have a single field of metadata attached to
+them.
+
+{% highlight lua %}
+local meta = items:get_metadata()
+print(dump(meta))
+meta = meta .. " ha!"
+items:set_metadata(meta)
+-- if ran multiple times, would give " ha! ha! ha!"
+{% endhighlight %}
+
+## More Methods
+
+Have a look at the
+[list of methods for an ItemStack](http://rubenwardy.com/minetest_modding_book/lua_api.html#methods_5).
+There are a lot more available than talked about here.