Mantis - Croquet
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2796 Hedgehog major always 02-14-06 22:39 04-02-06 02:38
0002796: Cannot carry portal into another space
Click on the grab icon on a portal frame, to carry it. This works while you are in the original space but when you try to carry the portal frame into one of the other spaces the frames you have grabbed are dropped and left behind when you cross a portat into a new space.
related to 0004488resolved mpm should have an easy way for users to ask for a two way portal 

03-07-06 21:30   
as discussed in the conference call monday, we need to carry a postcard into the new space rathe r than simply dropping the portal.
03-30-06 18:29   
I will writing up the stuff to allow you to carry a postcard, but... this will lead to madness. In order to resolve a postcard, you need to have the entire Island locally. This is a lot of overhead. If you have a world with 10 window/postcards from 10 different Islands, then all of these Islands need to be replicated locally. Good luck with that...

03-30-06 19:59   
I'm not quite following what the proposed postcard is to:
a) The new island contains a postcard to the original TWindow in the original island that contained the window?
b) The new island contains a new COPY of a TWindow, which contains a TPortal, which links via postcard to the possibly third island that the original portal led to?

In Dormouse, we dealt with carrying objects to another island in a uniform way matching (b), which matched what happens with the avatar itself:

1. When an avatar is carrying something and leaves an island, the avatar and everything it is carrying is removed from the original island.

2. When an avatar is carrying something and enters a new island, a new avatar is created on the new island, and everything it is carrying is COPIED over to the new island.

Note that there is an additional problem: The original TWindow/TPortal linked to another TWindow/TPortal which pointed back to it. The TPortal that the far end of the portal points to has now been deleted! There are two solutions here:

a. In Dormouse, all portals were one-way. If you want a door that works both ways, you create two portals back-to-back. This has the nice property that it works with copies. (Dormouse allows any object to be copied. Bidirectional portals would create a many-to-one problem.)

b. Very late in Dormouse, we created objects that maintain back pointers to things in other worlds that reference them. When something gets transferred, we send messages back to tell them to update to point to the new place. Of course, this creates all sorts of issues with replicated messages between islands, so I'm not advocating this solution in general.
04-01-06 00:42   
Hi Guys - Correct me if I'm wrong but didn't we jointly decide that this version won't allow you to carry portals between spaces (islands, really)? I do remember a discussion towards that end but maybe this here is the long-term how-to-fix-it-really-discussion, not the short-term one?!
04-02-06 02:38   
I don't recall the discussion on how to dispose of this.
My comments are regarding a long term fix.

My opinion is that this is a major part of the Croquet story, and we shoudn't leave it to developer's to roll their own over the lifetime of Hedgehog. I do NOT think, though, that we need this capabilty before release. So that still leaves the question of what to do for release -- How should we indicate notYetImplemented to end users?