[Bf-committers] Proposing a unique ID for Blender objects system, for use, with game engines. (Fergal Gribben)

[Ryan Inch]

Hi Fergal,
I would be very interested if you could share your UUID code with me as 
well, if you are willing.
I may be doing something similar with collections soon.

Ryan

On 2020-11-13 06:00 AM, bf-committers-request at blender.org wrote:
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> Today's Topics:
>
>     1. Proposing a unique ID for Blender objects system, for use
>        with game engines. (Juan Linietsky)
>     2. Re: Proposing a unique ID for Blender objects system, for use
>        with game engines. (Scott Wilson)
>     3. Re: Proposing a unique ID for Blender objects system, for use
>        with game engines. (Fergal Gribben)
>     4. Re: Proposing a unique ID for Blender objects system, for use
>        with game engines. (AMDBCG)
>     5. Re: Proposing a unique ID for Blender objects system, for use
>        with game engines. (Scott Wilson)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Thu, 12 Nov 2020 13:24:06 -0300
> From: Juan Linietsky <juan at godotengine.org>
> To: bf-blender developers <bf-committers at blender.org>
> Subject: [Bf-committers] Proposing a unique ID for Blender objects
> 	system, for use with game engines.
> Message-ID:
> 	<CAB2r+_uNNfy2U8qFfube+ifrw3UitOTnWmmw0wo-OZOzgYS0Pw at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Hi guys, lead Godot dev here.
>
> I wanted to discuss with you a problem we are often having that I am not
> certain how it can be solved entirely from our side, I add a proposal for
> this, but if you guys have a better recommendation, I'm very open to any
> ideas.
>
> Basically, Godot will import scenes (GLTF/FBX/DAE/etc) as they come from
> blender, and it generates the same object names, resource names, etc. as
> they come from Blender and the resource file.
>
> We use the same names so we can keep track of changes in the Blend file. If
> an object is moved, a material is changed, etc. we detect on re-import and
> everything is updated in Godot.
>
> This is especially more annoying in Godot than in other game engines,
> because Godot can read the whole Blender scene and keep it more or less
> intact, so users love using this for level design workflow (so they can
> design levels in Blender).
>
> So, the problem is that it often happens that for some reason, artists want
> to rename the objects in Blender. Be it because they didn't care at the
> beginning and they want to become more organized later, or because the
> scene became bigger and they need to make their naming of things more
> precise to navigate it around. In this situation, when something is renamed
> on the Blender side and re-exported, the game engines have no idea where
> this object went, so we need to either remove it (resulting in loss data)
> it or orphan it (resulting in duplicated data).
>
> While I do think that good practices solve this and this is probably not
> such an issue in a professional environment, truth is that game development
> has become a huge hobbyist activity, and our users find this situation
> constantly and are annoyed with it, and there is nothing we can do from our
> side.
>
> The obvious proposal to solve this would be to ask Blender whether it's
> possible to generate a unique object ID (UUID?) and make sure it does not
> change over time even if objects are renamed, then changing the exporters a
> bit to (optionally if selected in the export settings) add this information
> as extensions in the existing format (on GLTF it should be rather easy).
>
> If you guys think this is possible, it would be very helpful for us, if you
> have other ideas on how we could solve this, we are very open to discussion.
>
> Best
>
> Juan
>
>
> ------------------------------
>
> Message: 2
> Date: Thu, 12 Nov 2020 09:19:34 -0800
> From: Scott Wilson <gdragonmtn at gmail.com>
> To: bf-blender developers <bf-committers at blender.org>
> Cc: Juan Linietsky <juan at godotengine.org>
> Subject: Re: [Bf-committers] Proposing a unique ID for Blender objects
> 	system, for use with game engines.
> Message-ID:
> 	<CAK6zh-jEFCrW9fuC4eZtzrWFe3+DwTnvMGnorNEx7ZxTcuDSww at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Depending on how it is implemented, the unique IDs may be problematic. I
> know that some other 3d packages do have support for unique IDs, but if you
> reference in an asset multiple times, then you have duplicate IDs. If this
> is something that the developers are interested in doing, then I'd like to
> flag this as a possible issue.
>
> On Thu., Nov. 12, 2020, 8:24 a.m. Juan Linietsky via Bf-committers, <
> bf-committers at blender.org> wrote:
>
>> Hi guys, lead Godot dev here.
>>
>> I wanted to discuss with you a problem we are often having that I am not
>> certain how it can be solved entirely from our side, I add a proposal for
>> this, but if you guys have a better recommendation, I'm very open to any
>> ideas.
>>
>> Basically, Godot will import scenes (GLTF/FBX/DAE/etc) as they come from
>> blender, and it generates the same object names, resource names, etc. as
>> they come from Blender and the resource file.
>>
>> We use the same names so we can keep track of changes in the Blend file. If
>> an object is moved, a material is changed, etc. we detect on re-import and
>> everything is updated in Godot.
>>
>> This is especially more annoying in Godot than in other game engines,
>> because Godot can read the whole Blender scene and keep it more or less
>> intact, so users love using this for level design workflow (so they can
>> design levels in Blender).
>>
>> So, the problem is that it often happens that for some reason, artists want
>> to rename the objects in Blender. Be it because they didn't care at the
>> beginning and they want to become more organized later, or because the
>> scene became bigger and they need to make their naming of things more
>> precise to navigate it around. In this situation, when something is renamed
>> on the Blender side and re-exported, the game engines have no idea where
>> this object went, so we need to either remove it (resulting in loss data)
>> it or orphan it (resulting in duplicated data).
>>
>> While I do think that good practices solve this and this is probably not
>> such an issue in a professional environment, truth is that game development
>> has become a huge hobbyist activity, and our users find this situation
>> constantly and are annoyed with it, and there is nothing we can do from our
>> side.
>>
>> The obvious proposal to solve this would be to ask Blender whether it's
>> possible to generate a unique object ID (UUID?) and make sure it does not
>> change over time even if objects are renamed, then changing the exporters a
>> bit to (optionally if selected in the export settings) add this information
>> as extensions in the existing format (on GLTF it should be rather easy).
>>
>> If you guys think this is possible, it would be very helpful for us, if you
>> have other ideas on how we could solve this, we are very open to
>> discussion.
>>
>> Best
>>
>> Juan
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> https://lists.blender.org/mailman/listinfo/bf-committers
>>
>
> ------------------------------
>
> Message: 3
> Date: Thu, 12 Nov 2020 21:36:26 +0000
> From: Fergal Gribben <fgribben at gmail.com>
> To: bf-blender developers <bf-committers at blender.org>
> Cc: Scott Wilson <gdragonmtn at gmail.com>, Juan Linietsky
> 	<juan at godotengine.org>
> Subject: Re: [Bf-committers] Proposing a unique ID for Blender objects
> 	system, for use with game engines.
> Message-ID:
> 	<CAELP2O++M_dDE5xiviCaoWc8fahri4xNQYsaFAcwz9KZr2ktSw at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Hi Juan,
>
> Recently I've been experimenting with such a system, and the code I have
> works fine for what I need. I'm sure there are bugs in my code, and there
> are probably a few glaring omissions too, but in summary, the code can:
>
> - Generate a new UUID and assign it to a new object added to a scene
> - Generate a new UUID and assign it to a duplicated object
> - Remove the UUID from the list of known UUIDs when an object is deleted
>
> It also works across multiple scenes. I'm not sure if we're allowed to send
> zip files on this mailing list but if not I could send you the code
> directly? I've ripped it out of my addon so it works in isolation, and the
> best way to test it is to run Blender from the command line so you can see
> the list of UUIDs being printed as you add/delete objects.
>
> On Thu, 12 Nov 2020 at 17:20, Scott Wilson via Bf-committers <
> bf-committers at blender.org> wrote:
>
>> Depending on how it is implemented, the unique IDs may be problematic. I
>> know that some other 3d packages do have support for unique IDs, but if you
>> reference in an asset multiple times, then you have duplicate IDs. If this
>> is something that the developers are interested in doing, then I'd like to
>> flag this as a possible issue.
>>
>> On Thu., Nov. 12, 2020, 8:24 a.m. Juan Linietsky via Bf-committers, <
>> bf-committers at blender.org> wrote:
>>
>>> Hi guys, lead Godot dev here.
>>>
>>> I wanted to discuss with you a problem we are often having that I am not
>>> certain how it can be solved entirely from our side, I add a proposal for
>>> this, but if you guys have a better recommendation, I'm very open to any
>>> ideas.
>>>
>>> Basically, Godot will import scenes (GLTF/FBX/DAE/etc) as they come from
>>> blender, and it generates the same object names, resource names, etc. as
>>> they come from Blender and the resource file.
>>>
>>> We use the same names so we can keep track of changes in the Blend file.
>> If
>>> an object is moved, a material is changed, etc. we detect on re-import
>> and
>>> everything is updated in Godot.
>>>
>>> This is especially more annoying in Godot than in other game engines,
>>> because Godot can read the whole Blender scene and keep it more or less
>>> intact, so users love using this for level design workflow (so they can
>>> design levels in Blender).
>>>
>>> So, the problem is that it often happens that for some reason, artists
>> want
>>> to rename the objects in Blender. Be it because they didn't care at the
>>> beginning and they want to become more organized later, or because the
>>> scene became bigger and they need to make their naming of things more
>>> precise to navigate it around. In this situation, when something is
>> renamed
>>> on the Blender side and re-exported, the game engines have no idea where
>>> this object went, so we need to either remove it (resulting in loss data)
>>> it or orphan it (resulting in duplicated data).
>>>
>>> While I do think that good practices solve this and this is probably not
>>> such an issue in a professional environment, truth is that game
>> development
>>> has become a huge hobbyist activity, and our users find this situation
>>> constantly and are annoyed with it, and there is nothing we can do from
>> our
>>> side.
>>>
>>> The obvious proposal to solve this would be to ask Blender whether it's
>>> possible to generate a unique object ID (UUID?) and make sure it does not
>>> change over time even if objects are renamed, then changing the
>> exporters a
>>> bit to (optionally if selected in the export settings) add this
>> information
>>> as extensions in the existing format (on GLTF it should be rather easy).
>>>
>>> If you guys think this is possible, it would be very helpful for us, if
>> you
>>> have other ideas on how we could solve this, we are very open to
>>> discussion.
>>>
>>> Best
>>>
>>> Juan
>>> _______________________________________________
>>> Bf-committers mailing list
>>> Bf-committers at blender.org
>>> https://lists.blender.org/mailman/listinfo/bf-committers
>>>
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> https://lists.blender.org/mailman/listinfo/bf-committers
>>
>
> ------------------------------
>
> Message: 4
> Date: Thu, 12 Nov 2020 18:20:24 -0700
> From: AMDBCG <amdbcg at gmail.com>
> To: bf-committers at blender.org
> Subject: Re: [Bf-committers] Proposing a unique ID for Blender objects
> 	system, for use with game engines.
> Message-ID: <caadf069-5e91-61fd-dda1-d1f4f2bac9ec at gmail.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
> Python has an id for each object that can be referenced in your Blender
> importer
>
> https://www.programiz.com/python-programming/methods/built-in/id - where
> id is the main id of the object
>
> -Robert Fornof (amdbcg)
>
> On 11/12/2020 9:24 AM, Juan Linietsky via Bf-committers wrote:
>> Hi guys, lead Godot dev here.
>>
>> I wanted to discuss with you a problem we are often having that I am not
>> certain how it can be solved entirely from our side, I add a proposal for
>> this, but if you guys have a better recommendation, I'm very open to any
>> ideas.
>>
>> Basically, Godot will import scenes (GLTF/FBX/DAE/etc) as they come from
>> blender, and it generates the same object names, resource names, etc. as
>> they come from Blender and the resource file.
>>
>> We use the same names so we can keep track of changes in the Blend file. If
>> an object is moved, a material is changed, etc. we detect on re-import and
>> everything is updated in Godot.
>>
>> This is especially more annoying in Godot than in other game engines,
>> because Godot can read the whole Blender scene and keep it more or less
>> intact, so users love using this for level design workflow (so they can
>> design levels in Blender).
>>
>> So, the problem is that it often happens that for some reason, artists want
>> to rename the objects in Blender. Be it because they didn't care at the
>> beginning and they want to become more organized later, or because the
>> scene became bigger and they need to make their naming of things more
>> precise to navigate it around. In this situation, when something is renamed
>> on the Blender side and re-exported, the game engines have no idea where
>> this object went, so we need to either remove it (resulting in loss data)
>> it or orphan it (resulting in duplicated data).
>>
>> While I do think that good practices solve this and this is probably not
>> such an issue in a professional environment, truth is that game development
>> has become a huge hobbyist activity, and our users find this situation
>> constantly and are annoyed with it, and there is nothing we can do from our
>> side.
>>
>> The obvious proposal to solve this would be to ask Blender whether it's
>> possible to generate a unique object ID (UUID?) and make sure it does not
>> change over time even if objects are renamed, then changing the exporters a
>> bit to (optionally if selected in the export settings) add this information
>> as extensions in the existing format (on GLTF it should be rather easy).
>>
>> If you guys think this is possible, it would be very helpful for us, if you
>> have other ideas on how we could solve this, we are very open to discussion.
>>
>> Best
>>
>> Juan
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> https://lists.blender.org/mailman/listinfo/bf-committers
>
> ------------------------------
>
> Message: 5
> Date: Thu, 12 Nov 2020 17:51:03 -0800
> From: Scott Wilson <gdragonmtn at gmail.com>
> To: bf-blender developers <bf-committers at blender.org>
> Subject: Re: [Bf-committers] Proposing a unique ID for Blender objects
> 	system, for use with game engines.
> Message-ID:
> 	<CAK6zh-jWEDzQgVdgM3i52VcGeOS9r3Dn9eZX=Jv=iH-PN3-hAw at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> That's only valid for the lifetime of the object, though (it uses the
> memory location of the object). If you restart Blender, delete the Python
> object, or create a new Python object that points to the same memory in C,
> then all the IDs will likely be different for the same object in C. Also,
> the C objects' memory locations will likely change between Blender
> restarts, and deletions.
>
> On Thu., Nov. 12, 2020, 5:20 p.m. AMDBCG via Bf-committers, <
> bf-committers at blender.org> wrote:
>
>> Python has an id for each object that can be referenced in your Blender
>> importer
>>
>> https://www.programiz.com/python-programming/methods/built-in/id - where
>> id is the main id of the object
>>
>> -Robert Fornof (amdbcg)
>>
>> On 11/12/2020 9:24 AM, Juan Linietsky via Bf-committers wrote:
>>> Hi guys, lead Godot dev here.
>>>
>>> I wanted to discuss with you a problem we are often having that I am not
>>> certain how it can be solved entirely from our side, I add a proposal for
>>> this, but if you guys have a better recommendation, I'm very open to any
>>> ideas.
>>>
>>> Basically, Godot will import scenes (GLTF/FBX/DAE/etc) as they come from
>>> blender, and it generates the same object names, resource names, etc. as
>>> they come from Blender and the resource file.
>>>
>>> We use the same names so we can keep track of changes in the Blend file.
>> If
>>> an object is moved, a material is changed, etc. we detect on re-import
>> and
>>> everything is updated in Godot.
>>>
>>> This is especially more annoying in Godot than in other game engines,
>>> because Godot can read the whole Blender scene and keep it more or less
>>> intact, so users love using this for level design workflow (so they can
>>> design levels in Blender).
>>>
>>> So, the problem is that it often happens that for some reason, artists
>> want
>>> to rename the objects in Blender. Be it because they didn't care at the
>>> beginning and they want to become more organized later, or because the
>>> scene became bigger and they need to make their naming of things more
>>> precise to navigate it around. In this situation, when something is
>> renamed
>>> on the Blender side and re-exported, the game engines have no idea where
>>> this object went, so we need to either remove it (resulting in loss data)
>>> it or orphan it (resulting in duplicated data).
>>>
>>> While I do think that good practices solve this and this is probably not
>>> such an issue in a professional environment, truth is that game
>> development
>>> has become a huge hobbyist activity, and our users find this situation
>>> constantly and are annoyed with it, and there is nothing we can do from
>> our
>>> side.
>>>
>>> The obvious proposal to solve this would be to ask Blender whether it's
>>> possible to generate a unique object ID (UUID?) and make sure it does not
>>> change over time even if objects are renamed, then changing the
>> exporters a
>>> bit to (optionally if selected in the export settings) add this
>> information
>>> as extensions in the existing format (on GLTF it should be rather easy).
>>>
>>> If you guys think this is possible, it would be very helpful for us, if
>> you
>>> have other ideas on how we could solve this, we are very open to
>> discussion.
>>> Best
>>>
>>> Juan
>>> _______________________________________________
>>> Bf-committers mailing list
>>> Bf-committers at blender.org
>>> https://lists.blender.org/mailman/listinfo/bf-committers
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> https://lists.blender.org/mailman/listinfo/bf-committers
>>
>
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>
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>
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