DefinitionsItem budget - The sum of the stats of an item. See Item Level for more information

Item level or short ilvl - The item level of an item is what determines its item budget in the same rarity and slot

Slot or item slot - The slot in which the item can be equipped

Rarity - The rarity of an item. Examples are uncommon, rare, epic, legendary

Tier - A loot tier. Molten Core was Tier 1, Blackwing Lair Tier 2, and so on

Class - The class of a toon: Warrior, Priest, Rogue, and so on

Spec - The spec a class plays: Protection, Arms, Fury, Restoration, and so on

White stats - The inherent stats of an item which do not depend on choices of Blizzard's itemization. These
are: armor of an item, white dps on a weapon

Green stats - All the stats that are not white stats on an item

как видно количество ГП определяется не только от итем лвл шмота, но также еще и от самих статов, которые тем или иным путем бафнут игрока, выбирающего шмотку.

2 - Design of the GP formula

When designing the GP formula the following requirements were set:
Total GP for each class/spec should be ideally the same.
Items of a whole new and better tier should be increasingly more expensive. A factor of two was chosen for each tier.
Each item should cost as much GP as it's power according to the class/spec that uses it.

учитывая пункт 1 - создается ГП формула, получается то число, которое мы видим в аддоне для определенной шмотки.

While the relative item budget between slots is widely known (Item Level) there are class/spec combinations for which an item is more beneficial than others. These depend on how the class/spec is designed and what kind of stats it prefers or primarily uses. The cases we are more interested in are:

Shields: A tanking shield is used by shield capable tanking classes. In that case a tank is interested in both the white stats and the green stats of an item. A healing shield, which is used by shield capable healers, is used primarily, if not exlusively, for its green stats. This should be taken into account by the GP formula.

Weapons: Melee classes use both the green and white stats of a weapon. Both the dps of the weapon and the stats on it are useful. The white stats of a weapon are not at all useful for a hunter. This also needs to be taken into consideration.

Note: Casters get the white dps of a weapon and make it into spell power through some fixed formulas, so spell power on weapons is considered a white stat.

Ranged weapons: Hunters use ranged weapons for both their white stats and the green stats. This is not true for melee classes which use these items only for their green stats.

Off-hand weapons: These weapons are used by dual wielding classes/specs and because of the off hand weapons 50% damage modifier, the white stats on these items are severely less important. Obviously GP needs to account for this as well.

вот приводится пример о стоимости оружия для конкретных спеков, классов которая высчитывается исходя из ГП формулы.

With the above in mind the following formula was devised:

GP = 0.483 x 2 ilvl/26 + (rarity - 4) x slot mod

какбе сама ГП формула. рарити или ценность предмета для эпических шмоток состовляет 4, легенды 5.

3 - слот мод - как я понял, число указывающее принадлежность шмотки к тому или иному слоту в эквипе и зависит от конкретного класса персонажа =).

Slot modifiers depend on the slot each item can be equipped. In addition to that, the forementioned differences between the use of certain weapons/offhands is taken into consideration. This means some items have two possible GP values which depending on who uses them and how they are used.

The basic values slot modifiers for each slot are:

Slot mod

2H Weapon 2

1H Weapon 1.5

Head, Chest, Legs, 2H weapon 1 (не понятно почему 2h weapon здесь считается как 1, видимо для войнов)

Shoulder, Hands, Waist, Feet, Trinket 0.75

Wrist, Neck, Back, Finger, Off-hand,
Shield, Wand, Ranged Weapon 0.5

Опять же приведен пример для различных классов персонажей -

Under certain circumstances a different modifier is used. These are:

2H Weapon:
If it is going to be used as an offhand (TG warriors for example) the modifier becomes 1 (down from 2)
If it is going to be used by a hunter the modifier becomes 1 (down from 2)

1H Weapon:
If it is going to be used by a hunter the modifier becomes 0.5 (down from 1.5)
If it is going to be used by a tank for tanking purposes the modifier becomes 0.5 (down from 1.5)
If it is going to be used as an off-hand the modifier becomes 0.5 (down from 1.5)

Shield:
If it is going to be used by a tank for tanking purposes the modifier becomes 1.5 (up from 0.5)

Ranged:
If it is going to be used by a hunter the modifier becomes 1.5 (up from 0.5)

То есть в зависимости от класса слот мод увеличивается или уменьшается, тем самым общая ГП формула изменяется в большую либо меньшую сторону, значение.

Далее мы видим таблицу с описанием ГП коэффициента (слот мода) уже для тех классов, у которых чаще всего бывает неразбериха с дуал вайлдом, либо с щитами и прочим.

Class/Spec MH OH/Shield Ranged Total

Tank with shield 0.5 1.5 0.5 2.5

2H melee 2 - 0.5 2.5

Hunter 2H 1 - 1.5 2.5

Hunter MH+OH 0.5 0.5 1.5 2.5

Dual-wield 2H 2 1 0.5 3.5

Caster with shield 1.5 0.5 0.5 2.5

по своим скормным рассчетам для оружия получается именно так как написано аддоном в самой вещи.
есть вопросы - выслушаю в венте или в игровом чате