Pixel movement messing with my code

ID:326542
 
Feb 22 2012, 12:39 pm
(See the best response by Solomn Architect.)
Code:
mob/var
    health

obj/beams/head
    var/damage
    icon='beams.dmi'
    icon_state="head"
    density=1
    damage=10
    Bump(mob/M)
        if(ismob(M))
            M.health -= damage
            del(src)
    New()
        spawn(20)
        del src
        ..()

obj/beams/tail
    icon='beams.dmi'
    icon_state="tail"
    density=1
    Move()
        var/T = new /obj/beams/tail(src.loc)
        T:dir=src.dir
        T:icon_state=src.icon_state
        T:icon=src.icon
        ..()
    New()
        spawn(20)
        del(src)
        ..()


mob/verb/kamehameha()
    var/fired
    if(fired) return
    if(usr.dir==null) return
    fired=1
    var/A = new /obj/beams/head(usr.loc)
    var/B = new /obj/beams/tail(usr.loc)
    A:dir=usr.dir
    B:dir=usr.dir
    if(A)
        walk(A,usr.dir)
        spawn(1)
        walk(B,usr.dir)
        spawn(19)
        fired=0


/*
    These are simple defaults for your project.
 */

world
    fps = 25      // 25 frames per second
    icon_size = 32    // 32x32 icon size by default

    view = 9     // show up to 6 tiles outward from center (13x13 view)


// Make objects move 8 pixels per tick when walking

mob
    step_size = 4

obj
    step_size = 8


Problem description:

Well the default pixel movement makes the beam act weird. like the beam goes about half a tile to the side of me. Any ideas how to fix it?
#1 Feb 22 2012, 1:33 pm
First of all, why are you using the depreciated ":" operator? the "." operator does exactly the same thing, but I digress. Your issue is:
mob/verb/kamehameha()
// ...
    fired=1
    var/A = new /obj/beams/head(usr.loc) <-- RIGHT THERE
    var/B = new /obj/beams/tail(usr.loc) <-- AND THERE
    A:dir=usr.dir
// ...


You're specifying the tile location of the target variables, but not the exact pixel location. That just requires a few more simple references and variables, but that's why your beam is off center from the player. I suggest looking up the step_x and the step_y variables to help you out. Extremely simple fix, should be really quick. It'll just require adding a little more code, I see no need to change anything. (Except the : operators...)
#2 Feb 22 2012, 1:53 pm
if i use the "." it says that the A.dir is an undefined var anyways im looking into the step vars now.
#3 Feb 22 2012, 2:24 pm
Best response
Ah, I see now. Try this:

mob/verb/kamehameha()
// ...
    var/obj/beams/head/A = new/obj/beams/head
    var/obj/beams/tail/B = new/obj/beams/tail
    A.dir=usr.dir
    B.dir=usr.dir
// ...

I suggest you use this method, as the : operator does not check whether the variable is valid for the referenced object at compile time. The . operator does. This minimizes chance for run-time errors related to the code. If you reference a variable not associated with the object, you'll get an error at run-time when you attempt to use the function.

Apologies for being off-topic. I was merely showing you what is a much more preferred solution. The : operator is perfectly fine, but you have to be careful. The . is the safest.
#4 Feb 22 2012, 5:09 pm
If pixel movement is messing up your projectiles, and pixel movement is not wanted then remove it and its entirety.

If you were planning on setting up a normal projectile system without having to have that unnecessary clot of var/obj/blahblah then you could do it this way:

obj/projectile
    var/mob/owner // the owner of the projectile
    var/movementspeed = 0 // how fast the projectile moves
    var/distance = 0 // not setting this will delete the projectile on create
    var/damage = 0 // the amount of damage the projectile does
    bullet
        icon = 'bullet.dmi'
        movementspeed = 1 // moves every tenth of a second
        distance = 5 // only moves 5 tiles
        damage = 10 // static damage of 10
    
    Bump(mob/m)
        if(istype(m)) // check if the atom being bumped is a /mob type
            m.takedamage(damage) // causes the player that it bumps to take damage
        del(src) // delete the projectile once it has bumped
    
    New(var/turf/newloc, var/newdir, var/mob/newowner)
        ..()
        loc = newloc
        dir = newdir
        owner = newloc
        spawn(-1)
            fireprojectile()
    
    proc/fireprojectile()
        if(!owner || !distance || !damage) // only fire if variables are set
            return
        for(var/i = distance, i > 0, i--) // lets get loopy
            if(!owner) // break the loop if there is no present owner
                break
            step(src, dir) // move!
            sleep(movementspeed) // wait out the movement delay to move again
        del(src) // delete the projectile once it runs out of distance

mob/verb/shootbullet()
    new/obj/projectile/bullet(get_step(usr, dir), dir, usr)
    // get_step(usr, dir) - finds the turf that is located infront of the usr
    // dir - the direction you are facing
    // usr - yourself, to be set as the owner

#5 Feb 22 2012, 5:22 pm
You have posted the same exact broken, terrible code in the past. Are you trying at all?