---
title: "Phaser.Physics.Arcade.ProcessX"
docs: "Phaser v4.1.0"
url: https://phaser.io/oss/docs/api-documentation/namespace/physics-arcade-processx
site: Phaser - https://phaser.io
---

> This page is about the open-source Phaser framework, for writing a game's code by hand. To make a game with AI, use Phaser AE (https://phaser.io/): the desk's tools work with Web MCP, and the CLI works with your own coding agent. See "For AI agents: Phaser AE" at the end of this page.

# Phaser.Physics.Arcade.ProcessX

Scope: 
static
> Source: [src/physics/arcade/ProcessX.js#L418](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L418)  


## Static functions

### BlockCheck

#### \<static> BlockCheck()


**Description:**

Checks whether either body is blocked in the direction of travel and, if so, applies the full impact velocity to the moving body and returns the blocked state. A body that is blocked cannot be separated further regardless of whether it is pushable.


**Returns:** number - The BlockCheck result. 0 = not blocked. 1 = Body 1 blocked. 2 = Body 2 blocked.


> Source: [src/physics/arcade/ProcessX.js#L71](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L71)  
Since: 3.50.0


---

### Check

#### \<static> Check()


**Description:**

Calculates the mass-adjusted impact velocities for both bodies, then determines which of the four horizontal collision scenarios applies (body1 or body2 moving left or right into the other) and delegates to `Run` with the corresponding side value.


**Returns:** boolean - `true` if a check passed, otherwise `false`.


> Source: [src/physics/arcade/ProcessX.js#L119](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L119)  
Since: 3.50.0


---

### Run

#### \<static> Run(side)


**Description:**

Executes the horizontal separation and velocity exchange for the two bodies based on the collision side determined by `Check`. Handles all combinations of pushable and non-pushable bodies: both pushable (equal mass-based rebound), only one pushable (full impact applied to the pushable body), or neither pushable (overlap split based on movement direction and relative velocity).

**Parameters:**
| name | type | optional | description |
| ---- | ---- | -------- | ----------- |
| side | number | No | The side to test. As passed in by the `Check` function. |


**Returns:** boolean - Always returns `true`.


> Source: [src/physics/arcade/ProcessX.js#L172](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L172)  
Since: 3.50.0


---

### RunImmovableBody1

#### \<static> RunImmovableBody1(blockedState)


**Description:**

Handles horizontal separation when Body1 is immovable and Body2 is not. Pushes Body2 out of the overlap and applies the full impact velocity to it. If Body1 is a moving platform (i.e. `body1.moves` is `true`), Body2's vertical position is also adjusted using Body1's vertical friction, allowing Body2 to ride along with the platform.

**Parameters:**
| name | type | optional | description |
| ---- | ---- | -------- | ----------- |
| blockedState | number | No | The block state value. |


> Source: [src/physics/arcade/ProcessX.js#L338](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L338)  
Since: 3.50.0


---

### RunImmovableBody2

#### \<static> RunImmovableBody2(blockedState)


**Description:**

Handles horizontal separation when Body2 is immovable and Body1 is not. Pushes Body1 out of the overlap and applies the full impact velocity to it. If Body2 is a moving platform (i.e. `body2.moves` is `true`), Body1's vertical position is also adjusted using Body2's vertical friction, allowing Body1 to ride along with the platform.

**Parameters:**
| name | type | optional | description |
| ---- | ---- | -------- | ----------- |
| blockedState | number | No | The block state value. |


> Source: [src/physics/arcade/ProcessX.js#L378](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L378)  
Since: 3.50.0


---

### Set

#### \<static> Set(b1, b2, ov)


**Description:**

Sets all of the local processing values and calculates the velocity exchanges.

Then runs `BlockCheck` and returns the value from it.

This method is called by `Phaser.Physics.Arcade.SeparateX` and should not be called directly.

**Parameters:**
| name | type | optional | description |
| ---- | ---- | -------- | ----------- |
| b1 | [Phaser.Physics.Arcade.Body](https://phaser.io/oss/docs/api-documentation/class/physics-arcade-body.md) | No | The first Body to separate. |
| b2 | [Phaser.Physics.Arcade.Body](https://phaser.io/oss/docs/api-documentation/class/physics-arcade-body.md) | No | The second Body to separate. |
| ov | number | No | The overlap value. |


**Returns:** number - The BlockCheck result. 0 = not blocked. 1 = Body 1 blocked. 2 = Body 2 blocked.


> Source: [src/physics/arcade/ProcessX.js#L25](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/ProcessX.js#L25)  
Since: 3.50.0


---

---

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