superPilipala Spinebot's reply oversimplified the situation, so I would like to clarify our actual position.
Godot does support exporting C# projects to Android and iOS. However, that does not mean providing and maintaining Android and iOS export templates for the Spine custom engine module is a straightforward addition. Our previous investigation found that supporting this particular combination involves nontrivial work related to Godot's C# mobile export pipeline, and we have not been able to prioritize the development and ongoing maintenance that would be required.
To answer your questions directly:
1. Will we provide Android and iOS export templates for the Spine Godot C# custom engine module?
At present, we are not actively developing those templates.
We have not decided against supporting them in the future, but there is no active development on them at present.
2. Is there a planned version or milestone?
No. There is currently no target version or milestone for this work, so I cannot give you a concrete release date.
3. Does that mean the complete C# integration is permanently desktop only?
No. We do not consider it permanently desktop only.
The practical issue is one of development priorities and resources. Maintaining the Spine Runtimes across the many game engines and frameworks we support, and keeping them compatible with changes and new features in Spine itself, already requires substantial development work. We have therefore not been able to prioritize further development of the C# mobile export path for spine-godot.
The current situation is that the Spine Godot C# custom module does not have Android or iOS export templates provided by us.
4. What is the official migration path for an existing project using SpineSprite, SpineSlotNode, AnimationState, and the other module APIs?
There is currently no official migration path that preserves that integration unchanged while moving the project to Android or iOS.
Depending on the project, it may be possible to use another Spine Runtime integration, build on the lower level Spine Runtime APIs, or modify the spine-godot runtime for the project's specific requirements. However, those approaches are not equivalent to having an officially maintained Android or iOS template for the existing C# module, and I do not want to suggest otherwise.
I also want to clarify one broader point regarding the fact that Spine is commercial software.
A Spine license gives you the right to use the Spine Editor and the Spine Runtimes under the terms of the license. It does not constitute a guarantee that every Spine Runtime will support every platform, language, engine configuration, or combination of features that a particular project may require.
We provide runtimes for a wide range of engines and frameworks, as well as lower level runtimes that developers can use for custom integrations. The runtime source is also available so that developers can adapt an integration to requirements that are not covered by the configurations we officially provide and maintain.
That does not make your request unreasonable. Android and iOS support for the C# module would certainly be useful, and we understand why it matters for a project that has already been built around that API. However, the fact that this configuration would be useful does not by itself make it a feature that we have committed to provide as part of the Spine license.
Given our current team structure, we do not have staff dedicated exclusively to bug fixes and improvements for spine-godot. Development and maintenance of the runtime are handled alongside our other runtime and Spine development responsibilities. As a result, some spine-godot requests and improvements have remained open considerably longer than we would ideally like.
We would like to improve this situation, but at present we cannot provide a specific timeline for when particular spine-godot improvements, including Android and iOS support for the C# module, will be addressed.
