Elements disappear without reason

[Zomis]

Bug Report: Elements disappear without reason

• Versions: Probably many.
  Bug Type: Game Engine, Custom Elements
  Example Level: For bug #2. http://www.zomis.net/rnd/download.php?id=546
  Location: Level Play, Custom Elements

Comments:
1. A custom element 1 with the settings "Can move when pushed" and "Can dig custom element 1" disappears immeadiatly.

2. In a small attempt of continuing with Solomon's Key 2, I discovered a bug with a Custom Element which changes for no intended reason. Seems like the engine emulates a "dig custom element 2" even though custom element 2 was digged by another custom element 1 earlier

[Holger]

Strange... I wasn't able to reproduce the second bug with playing your level, but I could clearly see it in your tape (so it also seems to be a timing issue).

These bugs also need further investigation...

[Zomis]

Yes, indeed it is a timing thing. I didn't succeed in reproducing the second bug either always, had to try a couple of times.

>These bugs also need further investigation...

Does that mean that you put it up on some list for some thing to do later? Or does it mean that you need help with investigating what exactly might cause it?

[Holger]

No, I think I already know the reason why this happens -- when the digging CE is removed ("changes to empty space"), a temporary field storing the dug element is not cleared at the same time, apparently causing the second digging element to vanish (which is not 100% clear why).

Completely fixing this bug needs changes at every place where an element is removed (and there are a lot of such places in the code), so I will have to find out all the places which can also trigger this bug, and how to change it in a way that does not break any tape. This will take a lot of time, and I probably won't start it immediately, so this bug has to go to a list of "known bugs" for some time...