Problème pour des lumières

//Réinitialise
alpha = 0

//Si il y a un generateur de lumière très proche
if distance_to_point(instance_nearest(x,y,obj_parent_light).x,instance_nearest(x,y,obj_parent_light).y) < 35
{
alpha = instance_nearest(x,y,obj_parent_light).light_puissance
}

//Calcule la lumière
if alpha < instance_nearest(x - 32,y,obj_empty).alpha - 0.5
{
alpha = instance_nearest(x - 32,y,obj_empty).alpha - 0.5
}

if alpha < instance_nearest(x + 32,y,obj_empty).alpha - 0.5
{
alpha = instance_nearest(x + 32,y,obj_empty).alpha - 0.5
}

if alpha < instance_nearest(x,y - 32,obj_empty).alpha - 0.5
{
alpha = instance_nearest(x,y - 32,obj_empty).alpha - 0.5
}

if alpha < instance_nearest(x,y + 32,obj_empty).alpha - 0.5
{
alpha = instance_nearest(x,y + 32,obj_empty).alpha - 0.5
}