Unit Size

Unit Size is a mechanic that defines a unit's size in the game.

Definition
Only Selection Size can change as Model Size changes. Other unit sizes do not have relationship with each other.

Unit sizes are not directly set by a number in their data. Instead, sizes are standardized for all units, with the use of collision sizes and bound radius.

Size Values
The Collision Sizes and Bound Radius of units are not directly set by a number in their data. Instead, they are standardized for all units with the following hull sizes.

Both and 's Ancient uses the. Their exact collision size and bound radius can be found in.

Collision Size
Collision Size is a unit's internal size that cannot be passed through by other units, while phased movement allows units to ignore collision size and pass through other units. A unit's collision size can be shown with  with console enabled.

A unit's collision size is not directly affected by its model size or graphical model. Generally, collision size refers to the smallest possible distance between two units. Therefore, the smallest possible distance between two units is equal to the sum of the collision size of the units.

Collision size causes units to block each other with their bodies, and block units during pathfinding. Non-player-controlled units (i.e. lane creeps) do not try to path around the source that blocks them but simply walk against it as if it is not there. This effectively causes them to get stuck, until they change directions (e.g. when being aggro'd), or until the source that blocks them disappears.

Units with phased movement ignore the collision sizes of other units, causing both units to overlap. When multiple units overlap during the phase movement expiring, the units with lower collision size priority will be pushed away from the higher-priority collision size source as follows:

Collision size also affects illusion-creating sources. Since two heroes (or units) cannot be in the same coordinates without phased movement, and they will be pushed -distance away upon losing phased movement, regardless of the collision sizes. In the following table, and  have a collision size of  and  respectively. The illusions will spawn at different distances depending on the affected target's collision size as follows:


 * Example
 * casts  on an enemy  and . How far the Phantasm illusion will be spawned next to both of these enemy targets?


 * Collision Size:
 * Collision Size:
 * Collision Size:


 * Since both heroes' collision sizes are the same, the Phantasm illusion will spawn -distance away when does not have phased movement.
 * For the, the Phantasm illusion will spawn 87-distance away instead.

Ignoring Collision Size
Phased is a status that allows units to pass through other units, ignoring collision size. Phased units can freely walk through any other unit, including wards, but excluding buildings and trees. Other units can also walk through a stationary phased unit as if it is not there.

There are two different kinds of phased movement, pathing through units, and the rare kind which allows the unit to walk through anything, including buildings, cliffs and trees, which is more commonly referred to as unobstructed movement.

Certain abilities grant tree-walking, a buff that allows unobstructed movement through trees. All flying and unobstructed movement sources grant tree-walking as well.

Phased Movement
These abilities provide phased movement which allows moving through units:

The following units are permanently phased:

Unobstructed Movement
Free pathing (also known as unobstructed movement) allows affected units to path through buildings, cliffs and trees, on top of allowing them to path through other units. There is no limit to their movement and only a tiny amount of spells will block them. All sources of flying movement give units unobstructed movement. Uphill miss chance does not apply to flying units.

The following abilities provide unobstructed movement:

Flying Movement
Flying movement is similar to unobstructed movement, with only very small differences, one being that flying units hover a certain distance above the ground with unobstructed vision and that even fewer abilities block flying movement.

When a unit turns to Flying Movement, although its hitbox and model ascend above the z-axis, both its collision size and bound radius are still on the ground. The following abilities provide Flying Movement while active:

Bound Radius
The Bound Radius determines the absolute coordinates of a unit in the game and acts as a pseudo-buffer for certain ability types' cast range values and attack range-related values. A unit's bound radius can be shown with  with console enabled.

Bound radius also affects the size of an area of effect, if an ability is cast as a ground-targeted ability, the affected target's bound size is also considered as a buffer range for ability, therefore increasing the ability's maximum area of effect range. However, if an ability is cast centered on the caster (with double), the caster's bound radius value is ignored and no buffer range is added.

Equations
For normal attacks:  Actual Attack Range = Total Attack Range + Attacker Bound Radius + Target Bound Radius 

For abilities: MAX Cast Range = Total Ability Cast Range + Target Bound Radius

MAX Effect Radius = Total Ability Effect Radius + Target Bound Radius

: Maximum Distance for Attackable Range
 * Example 1a
 * A is attacking . Without other attack range-increasing sources, what is the maximum distance a normal attack would hit between the attacker and the unit being attacked?


 * attack range:
 * bound radius:
 * bound radius:


 * Maximum attack range against


 * The has a  maximum attack range against . Since the Tower cannot move, the  attack range buffer does not apply in this case.


 * Example 1b
 * With Attack Buffer Range
 * is attacking . Without other attack range-increasing sources, what is the maximum distance a normal attack would hit between the attacker and the unit being attacked?


 * attack range:
 * bound radius:
 * bound radius:
 * Motion buffer distance:


 * Maximum attack range against


 * has a maximum attack range against, and her attack cancels when  is beyond  distance from her.
 * Therefore, units with a smaller bound radius will have a lesser actual attack range value against them.

: An Ability's Maximum Effect Radius Between Two Casters
 * Example 2
 * What is the maximum area of effect range for 's affecting ?
 * If acquires  via, what is the maximum area of effect range for Rubick's Song of the Siren affecting ?


 * max radius:
 * bound radius:
 * bound radius:


 * Maximum effect radius against :


 * Maximum effect radius against :


 * Therefore, Naga Siren's has a greater area of effect of  compared to 's.
 * Assuming both Rubick and Naga Siren are at ± distance apart, an acquired Song of the Siren via might not affect Naga Siren if she is not within the actual effect radius since Naga Siren has a smaller bound radius as shown in the diagram on the right.

Selection Box
The selection box (or hitbox) is the range size of a unit being clickable, or when drag is used to select units.

Most units have a minimum of two selection boxes, one exterior big cuboid, and at least one cuboid on the inside. For buildings, the cuboid inside might be larger than the exterior cuboid. Clicking outside the unit's selection box will not select the unit.

The selection box is bound to the unit's model and its values can be found using Workshop Tools. The selection boxes' size also scales with the current unit's model size. A unit's selection boxes can be shown with  with console enabled.

Certain cosmetic items change the value of the selection boxes due to having a different model as follows:
 * of 's.
 * Custom.

Has the following priority when the selection boxes of multiple units overlap:
 * The internal cuboid(s) ➤ The external cuboid ➤ The unit closest to the player's camera.



Model Size
A unit's Model Size is stored as a fixed scale value in  or. Model Size can be shown with both  and   with console enabled.

Model Size shown in  is equal to   in either   or.

It has no correlation with a unit's collision size or bound radius. However, increasing the model size increases the size of a unit's selection boxes.

Also, a unit's model animations do not determine the unit's current facing direction, certain ability interactions with the current unit's model may not correctly represent the current facing direction of the unit.

In most cases, ability animations with special model animations do not change the unit's facing direction. This includes all Taunt (Equipment) and the following abilities:

Different Model
The following sources directly change or replace the unit's current model. Certain abilities increase the model size as an effect as well, with more details can be found on their respective ability notes.

Percentage-Based Changes
All percentage-based model scale sources stack independently and additively of each other.

Total Model Size = Base Scale × (1 + Percentage-Based Scale i)


 * Example
 * currently has a model scale of 1.12. What is his current model scale upon activating ?


 * model scale increase: 30%


 * 1.12 × (1 + 0.3)


 * has a model scale of upon activating  as shown in the picture example on the left.

Edge Cases
In some edge cases, the unit's model size does affect gameplay and has some unique interactions between units and abilities.

Since a unit's model determines the entity attachments of projectiles, model size may indirectly affect attack animations and certain trajectories for projectiles. This may affect the following things:
 * The projectile of starts from the front end of the hero's weapon. The larger the hero model, the closer the starting point of the projectile is to the target. Hence, the projectile will reach the target in a slightly shorter time.
 * As shown in the right attachment, with 's original model scale, all attack projectiles are blocked by.
 * After casting and increasing its model scale, the front edge of her weapon is considered inside the  on certain attack animations, making some of her attack bypassing the Arena of Blood, and therefore damaging.
 * The same also applies to, who has certain attack animations releasing projectiles from the tip of the weapon.
 * with equipped may attack targets near the  within 150 range since the cosmetic uses a different attack animation in certain attack range.

Recent Changes
Размер существа 单位体积