# Velocity from Direction & Speed (Random Direction) Menu Path : **Velocity > [Set/Add] Velocity from Direction & Speed (Random Direction)** The **Velocity from Direction And Speed (Random Direction)** Block calculates a velocity for the particle based on a blend ratio between a random direction (per-particle), and the direction attribute. The Block then scales the final direction vector by a speed, and composes it with the velocity attribute. ![](Images/Block-VelocityFromDirectionAndSpeed(RandomDirection)Example.gif) ## Block compatibility This Block is compatible with the following Contexts: - [Initialize](Context-Initialize.md) - [Update](Context-Update.md) ## Block settings | **Setting** | **Type** | **Description** | | --------------- | -------- | ------------------------------------------------------------ | | **Composition** | Enum | **(Inspector)** Specifies how this Block composes the velocity attribute. The options are:
• **Set**: Overwrites the velocity attribute with the new value.
• **Add**: Adds the new value to the velocity attribute value.
• **Multiply**: Multiplies the velocity attribute value by the new value.
• **Blend**: Interpolates between the velocity attribute value and the new value. You can specify the blend factor between 0 and 1. | | **Speed Mode** | Enum | Specifies how to calculate the speed. The options are:
• **Constant**: Applies a constant speed which you set in the **Speed** property.
• **Random**: Applies a random speed between **Min Speed** and **Max** **Speed**. | ## Block properties | **Input** | **Type** | **Description** | | ------------------- | -------- | ------------------------------------------------------------ | | **Speed** | float | The speed multiplier to apply to the direction vector in order to calculate the velocity.
This property only appears if you set **Speed Mode** to **Constant**. | | **Min Speed** | float | The minimum speed multiplier to apply to the direction vector in order to calculate the velocity.
This property only appears if you set **Speed Mode** to **Random**. | | **Max Speed** | float | The maximum speed multiplier to apply to the direction vector in order to calculate the velocity.
This property only appears if you set **Speed Mode** to **Random**. | | **Blend Direction** | float | The blend percentage between the current direction attribute value and the newly calculated direction value. | | **Blend Velocity** | float | The blend percentage between the current direction attribute value and the newly calculated direction value.
This property only appears if you set **Composition** to **Blend**. |