VECTOR Weatherbox;
VECTOR Wind_direction; //Movement speed and direction

Wind_direction.x = 0;
Wind_direction.y = 0;
Wind_direction.z = -20;

BMAP* Weather_bmap = "raindrop.tga"; //The particle bmap

function Weather_part_event()
{
//keep the particle within the box
vec_set(my.x,vector(
cycle(my.x,camera.x-Weatherbox.x,camera.x+Weatherbox.x),
cycle(my.y,camera.y-Weatherbox.y,camera.y+Weatherbox.y),
cycle(my.z,camera.z-Weatherbox.z,camera.z+Weatherbox.z)));

//update the movement speed and direction
vec_set(my.vel_x,vector(Wind_direction.x,Wind_direction.y,Wind_direction.z));

my.lifespan = 100; // live forever
}

function Weather_part()
{
//place particles at random positions within the box
vec_set(my.x,vector(camera.x+random(Weatherbox.x*2)-Weatherbox.x,
camera.y+random(Weatherbox.y*2)-Weatherbox.y,
camera.z+random(Weatherbox.z*2)-Weatherbox.z));

my.bmap = Weather_bmap;
my.size = random(1)+2;
my.move = on;

my.function = Weather_part_event;
}

function CreateWeatherParticles(cx,cy,cz,numparticles)
{
Weatherbox.x = cx/2;
Weatherbox.y = cy/2;
Weatherbox.z = cz/2;

//create the particles
effect(Weather_part,numparticles,nullvector,nullvector);
}

my.move
Ist dieses Flag gesetzt, bewegt sich der Partikel mit seinem Geschwindigkeitsvektor und beschleunigt mit seiner Schwerkraftsbeschleunigung.
Wertebereich:
on - Partikel können sich bewegen
off - keine Partikelbewegung (default:off)