From prometheus.sma
Code:
/*
*
* Determines velocity (new_velocity) that
* you would set an entity to in order for
* it to go at "speed" from "origin1" to
* "origin2".
*
* By GHW_Chronic
*
*/
stock get_speed_vector(const Float:origin1[3],const Float:origin2[3],Float:speed, Float:new_velocity[3])
{
new_velocity[0] = origin2[0] - origin1[0];
new_velocity[1] = origin2[1] - origin1[1];
new_velocity[2] = origin2[2] - origin1[2];
new Float:num = floatsqroot(speed*speed / (new_velocity[0]*new_velocity[0] + new_velocity[1]*new_velocity[1] + new_velocity[2]*new_velocity[2]));
new_velocity[0] *= num;
new_velocity[1] *= num;
new_velocity[2] *= num;
return 1;
}