# SetParticlesDirection

## Description

Sets the initial direction of new particles when they emerge from the emitter. This can be used along with the SetParticlesAngle command to set the range of variation from this initial direction that new particles can choose. This also sets the initial speed of the particles by taking the length of the vector as units per second. For example if the initial direction is vx=10, vy=-15, particles will begin by moving to the right at a rate of 10 units per second and upwards at a rate of 15 units per second and will continue this rate of motion for their entire life unless influenced by forces added with AddParticlesForce.

## Definition

SetParticlesDirection( ID, vx, vy )

void agk::SetParticlesDirection( UINT ID, float vx, float vy )

## Parameters

- ID - The ID of the emitter to modify.
- vx - The x direction that particles will move initially.
- vy - The y direction that particles will move initially.