font standard_font= "Arial",1,20;

string npc1_str ="1.text";
string npc2_str ="2.text";
string npc3_str ="3.text";
string npc4_str ="4.text";
string npc5_str ="5.text";

text npc_txt
{
    layer = 22;
    pos_x = 0;
    pos_y = 300;
    font = standard_font;
    strings = 5;
    string = npc1_str; 
     flags = d3d;
   
} 

function npc_talks()
{
 while(1)
 {
      if (my.skill12 == 1) {npc_txt.string = npc1_str;} 
      if (my.skill12 == 2) {npc_txt.string = npc2_str;}  
      if (my.skill12 == 3) {npc_txt.string = npc3_str;} 
      if (my.skill12 == 4) {npc_txt.string = npc4_str;} 
      if (my.skill12 == 5) {npc_txt.string = npc5_str;} 
      
      if (my.skill12 > 5) {my.skill12 = 0;}
 wait(1);
 }
} 



function sprechen()
{
npc_txt.visible = on;
if (my.skill12 < 6) {my.skill12 += 1;}       
}   


action npc1
{
    npc_talks();//call this function only from this action 
    clip_size = 0;
    while (1)
    {
        
        temp.x = player.x - my.x;
        temp.y = player.y - my.y;
        temp.z = 0;
       
        
        
        my.skill10 = vec_dist(my.x, player.x);
        if (my.skill10 < 50) 
        {
             if (my.skill11 == 0)
            {
                npc_talks();
                my.skill11 = 50;
            }
        }
        else
        {
             my.skill11 = 0;
        }

        if(vec_dist(my.x,player.x)<500)//you need to set vec_dist that you want
        {
        if(key_l == 1)
        {
        sprechen();//call this function from action
        while(key_l == 1){wait(1);}
        }
        }
        else
        {
        my.skill2 = 0;
        npc_txt.visible = off;
        }
      
        wait (1);
    } 
}