Pushable Box Oddity

[dabyx]

Hi guys,

I need a bit of help again.

I have created a simple pushable sprite. Where it stops when hitting a wallblock.

The player should change image and animate when colliding and stop moving when the box also cannot move.

Everything works perfectly fine unless the player('s Y coord?) goes lower than the box and then back.

This makes the player NOT animate/change image and they pass through the box if against a wall.

However, the player will still push the box if able.

Also if the player('s Y coord?) goes higher than the box this does not produce the same bug.

I have attempted stripping code, rearranging and creating brand new, simpler scripts to test but always end up with the same result.

Could anyone shed some light on why this could be? I am stumped!

Thanks

Example Code for box pushing right
IF COLLISION 0
IF K > SETTINGA ;or if K = Y tried both - K = players Y coord
IF J < X ; if PLAYERS X coord is to the LEFT
IF KEY RIGHT
OTHER
LET IMAGE = 4 ;change to player push sprite
ANIMATE
ENDSPRITE
IF CANGORIGHT
SPRITERIGHT
ELSE
OTHER
LET IMAGE = 4
ANIMATE
UNDOSPRITEMOVE ;stop moving
ENDSPRITE
ENDIF
ENDIF
ENDIF
ENDIF
ENDIF

Example Code for Player


EVENT SPRITETYPE6

LET J = X
LET K = Y

IF KEY LEFT
   LET DIRECTION = LEFT
   LET IMAGE = 3
   IF X <= LEFTEDGE
       SCREENLEFT
       LET X = RIGHTEDGE
       EXIT
   ELSE
       IF CANGOLEFT
           SPRITELEFT
           ANIMATE
       ENDIF
   ENDIF
ENDIF

IF KEY RIGHT
   LET DIRECTION = RIGHT
   LET IMAGE = 2
   IF X >= RIGHTEDGE
       SCREENRIGHT
       LET X = LEFTEDGE
       EXIT
   ELSE
       IF CANGORIGHT
           SPRITERIGHT
           ANIMATE
       ENDIF
   ENDIF
ENDIF

IF KEY UP
  IF LADDERABOVE
     IF CANGOUP
       LET IMAGE = 11
    SPRITEUP
IF Q = 0
  BEEP 35
ENDIF
        LET DIRECTION = UP
 ANIMATE MEDIUM
   
    ENDIF
  ;ELSE ;I have tried cutting this block out in case it was an issue but does it either way...
   ;  SPRITELEFT
    ; IF LADDERABOVE
     ;ELSE
      ;  SPRITERIGHT
       ; SPRITERIGHT
        ;IF LADDERABOVE
     ; ELSE
      ;     SPRITELEFT
        ENDIF
     ENDIF
  ENDIF
ENDIF

IF KEY DOWN
  IF LADDERBELOW
   LET IMAGE = 11
     SPRITEDOWN
IF Q = 0
  BEEP 35
ENDIF
     LET DIRECTION = DOWN
  ANIMATE MEDIUM
;  ELSE
 ;    SPRITELEFT
  ;   IF LADDERBELOW
   ;  ELSE
    ;    SPRITERIGHT
     ;   SPRITERIGHT
      ;  IF LADDERBELOW
       ; ELSE
        ;   SPRITELEFT
        ENDIF
     ENDIF
ENDIF
ENDIF

IF KEY FIRE
   JUMP 7
ENDIF
FALL

IF DEADLY
   KILL
ENDIF

GETBLOCKS




[dabyx]

Oh and the bug happens whether the player ascends/descends a ladder or if they fall and then rise/SPRITEUP.

Basically always happens if the player is lower than the box at any point.

But if the player then climbs a ladder again, they can push the box properly.

[dabyx]

Adding a GIF  (sorry for low quality) which may help convey what I mean

GIF shows pushing correctly even when ascending but bugging out when going down a ladder.

Pushing GIF

[oss003]

I think the problem is the location for LET J = X and LET K = Y, the old coordinates of spritetype 6 are stored now.
After LET J = X and LET K = Y, SPRITEUP/DOWN/LEFT or RIGHT can be executed which changes the X and/or Y coordinates.
you can try to locate these lines at the end of EVENT SPRITETYPE6

For checking the coordinates, add these lines as first lines in EVENT SPRITETYPE6:

AT 0,0:DISPLAY J
PRINT ",":DISPLAY K
AT 0,8:DISPLAY X
PRINT",":DISPLAY Y

I can check the complete code if you upload the DELETEME.AGD file.

Greetings
Kees

[dabyx]

Ah that makes sense. I didn't even think of that, position of certain player code.

(Using sprite type 6 as a test as well but yeah, J=X and K=Y is also at the top of the player event)

I'll have another bash this week and test it recognising correct player X/Y coords.

If I can/can't sort it I'll reply again either way 😁

Thanks!!

(Really, really strange it only happens when the player's Y is higher than the box though!)

[dabyx]

Ok, I did some quick testing before examining my own code and I believe that this is something to do with the program itself

(Or at least my version/possibly bugged MPAGD)

Starting a new project and using only Minilop's code (hope that's alright chap!) for the player right/left/up and down ladders and their box code on the website the pushable box still behaves differently if the player's Y coord becomes greater.

Granted that this behaviour differs from my previous GIF but in this instance the player bounces against the box at all times UNLESS the player has been below the box and no higher. Which in this case they do not bounce but simply stick to it.

This pretty much confirms to me that it's an engine thing on my end at least.

Is this a bug? Not sure but at least I can sleep easy and work around it for now 🤣

Gif below of a test with Minilop's code showing bouncing against vs not:

ibb.co/VDM6m2G

[oss003]

Can you upload the DELETEME.AGD file of that example so I can have a look?

[dabyx]

Sure thing.

Here ya go

For now I've worked around it by checking if the player has been lower than the box and if so, if Player y = box y spawn a new box and remove the current one.

Attachments:

deleteme.agd (15.1 KB)

[ramon]

A different approach can inspire you from here: arcadegamedesigner.proboards.com/thread/1168/fun-solid-stackable-pushable