Stackable items

Stackable items are items that only take up one space in a player's inventory not being carried in note form. When multiple stackable items are carried in the inventory, a number is shown on the item's picture to indicate the quantity of items in the stack. Most items stored in the bank will stack, even if they don't stack in a player's inventory. A few exceptions would be brawling gloves, satchels, and the various forms of the morphic tool. Stackable items do not weigh anything, and cannot be withdrawn from the bank as a note.

Stackable items include bait, charms, runes, all arrows, all seeds, notes, and coins. Other stackable items include biscuits, bolts, bolt tips, darts, dart tips, nails, arrowtips, throwing knives, cannonballs, javelins, thrownaxes, feathers, arrow shafts, needles, thread, purple sweets, scrolls, skewer sticks, woad leaves, and proboscises. Also, swamp tar and anything made from swamp tar (such as swamp paste or guam tar) is always stackable.

Limit of a stack
The maximum number of an item that a player can hold in a stack is 2,147,483,647, as limited by a signed (positive and negative) 32-bit integer, i.e. 231 - 1.

Jagex would only be able to expand this if 64-bit integers were used instead, as unsigned (positive only) inte



gers do not exist as a primitive data type in Java. This would be problematic to implement, however, as it would require doubling the amount of storage space used for all item quantities. Using longs would enable up to 9,223,372,036,854,775,807 items in a stack.

Despite Java's lacking native support for unsigned arithmetic, a quick search through a computer's memory while it is playing RuneScape finds a 32-bit unsigned integer attached to every object in one's inventory that controls the amount of that object in the inventory slot. But, these variables are for local use only to draw the object, and changing them has no effect after the game updates the player's inventory.

It should also be noted that a player can own more than this amount of gold, but can only hold that many in a single stack. For instance, a player could hold 2,147,483,647 in an inventory and another 2,147,483,647 in his bank, so long as the two stacks are never combined.

In a recent question and answer session with Andrew Gower, he stated that they wouldn't switch to longs because there are too many lines of code to change in the RuneScape program.

Truncation convention
When referring to numbers, truncation is the removal of less significant digits from the end of a number. In RuneScape, stacks of items have their quantity truncated to reduce the number of characters required to show the quantity of an item in a stack.

For stacks of items containing less than 100,000, the amount is rendered precisely, such as "31633", and



the examine text is that of an individual item. For stacks of 100,000 or more, the examine text displays the exact number of items in the stack. The following conventions are used to display the quantity in a bank or inventory slot:

It should be noted that these truncation conventions are also applied to items other than coins.