Re: What does the "transparent" tag do?
Posted: Wednesday, 2nd February 2011, 16:21The 'transparent' tag prevents the squares of the vault from being associated with its map index, and from being marked with MMT_OPAQUE.
The former prevents the vault from, for example, showing up in death reports, as there is no association between the map coordinate and the vault.
MMT_OPAQUE needs some more explanation: By default, all vaults are marked with it, and that makes the level connectivity checking code (the one that finds isolated regions) assume that the vaults are non-passable. Quoting dungeon.cc:
"Don't peek inside MMT_OPAQUE vaults (all vaults are opaque by default) because vaults may choose to create isolated or otherwise cause connectivity issues even if the map is travel-passable."
The 'transparent' tags cancels that behaviour, so the passability of vaults that have it is checked in accordance with their actual terrain.
Other use cases include dummy portal vault entries (they're just portals, they cannot affect connectivity), vaults that place uniques (they just place monsters---same rationale).
The former prevents the vault from, for example, showing up in death reports, as there is no association between the map coordinate and the vault.
MMT_OPAQUE needs some more explanation: By default, all vaults are marked with it, and that makes the level connectivity checking code (the one that finds isolated regions) assume that the vaults are non-passable. Quoting dungeon.cc:
"Don't peek inside MMT_OPAQUE vaults (all vaults are opaque by default) because vaults may choose to create isolated or otherwise cause connectivity issues even if the map is travel-passable."
The 'transparent' tags cancels that behaviour, so the passability of vaults that have it is checked in accordance with their actual terrain.
Other use cases include dummy portal vault entries (they're just portals, they cannot affect connectivity), vaults that place uniques (they just place monsters---same rationale).