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About building parametric objects with GDL.

Changes in the Graphisoft Library



"These objects <...> (red in attacment) seem to have a different Unique ID from previous versions, causing our object library that uses them as subtypes to not find them correctly. Is this intentional?"

Changed GUIDS in following:

Distribution Element
AC 26: {9BCE6139-F733-4E13-B439-AAF1AF232B89}-{D3E1DBCC-14B8-446D-88D3-E8A43E219682}
AC 27: {3D22AA23-782D-4368-8407-807FBAFCB031}-{AE0FE9B7-B57E-4A63-B751-B9A230A108EF}


Distribution Flow Element
AC 26: {30E58E66-1DA9-4D20-9341-700170100E12}-{C1C1305C-9A6B-4444-94AB-29520AC140F7}
AC 27: {7726F3A8-E76B-4D3F-A110-DE0BA98EF403}-{57E0C17E-2A7A-437F-A32B-4C903CC85CE7}


Flow Device
AC 26: {D39DF9D9-2191-4C4D-B004-2E8C1B298D7C}-{2526EDC4-93F0-4323-A579-F64547D0BBEF}
AC 27: {C0B99FA1-3EB6-445F-AC86-B9C466A9459F}-{1B894F91-187D-427F-B0CD-61CE0CD1CE4C}


Flow Equipment
AC 26: {0D6515ED-B372-41C6-8291-C527CE94BA43}-{A62B169E-C148-4A01-AD5B-F2BDFE5F69B3}
AC 27: {D58ADD1C-ED59-4763-B239-1F7D7E997682}-{5C704256-A1A9-4079-8F13-402DCD480806}


Flow Segment
AC 26: {8BDD43BD-7237-46D8-8AB1-76D794D6213A}-{9FE16543-FFC0-4CCE-AF67-7E6886DFD25E}
AC 27: {0ED8B445-401E-459D-96AA-39A2DD4DE28E}-{853243DF-7B4B-4852-B3D8-71C0D5515ADF}

Would You recommend using Your library's objects as subtypes in the future as well?








Barry Kelly

The MEP objects in 27 are new as far as I know and not compatible with the older objects.

What happens if you load the 'Migration' libraries along with the 27 library?



One of the forum moderators.
Versions 6.5 to 27
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We look for a future proof solution, how to build (local)connections to Graphisofts libraries. Those out of Graphisofts global library contents.  This considers the local Finnish distributor shared library, used in hundreds of offices, in thousands of projects. We can't ask all of them to use migration libraries for new projects.


Perhaps just better communication about changes (how to drive them to 3rd party solutions) and reasons behind would help.


Feature without explanation (or immediate fix) is a bug...



To be clear, these are not actual placeable objects, but objects that define subtypes, defined in the builtin library  (BuiltinLibraryParts.lcf) .


(1) The hierarchy of Distribution Element subtypes is identical between 26 and 27, (2) the object parameters they define seem to be identical, and (3) only four [five] of the many subtypes (image below [also should have the Distributed Flow Element highlighted]) have a new GUID, which makes me think this could be unintentional. Of course there might be some reason to only change the GUIDs while everything else remains unchanged that we aren't aware of.




Peter Baksa



Yes there changes were intentional, caused by the renewal of the MEP tools.

Opening a plan in AC27 from a previous version, MEP objects are converted to simple Objects (with the chair icon). The migration library is needed for these to function as standalone objects.

To use objects with the MEP tools, the libraries have to be re-saved with the new subtype IDs. This can be done fairly easy by de-compiling them to source code using LP_XMLConverter, some find&replace, then compiling again.

Routing elements' scripts need a change, if you need to access the attributes of the MEP system selected in the route settings dialog:


Edit: I've uploaded the subtype ID pairs in this topic:



Péter Baksa
Software Engineer, Library as a Platform
Graphisoft SE, Budapest
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