Add guideline for evaluating proposals

[clayjohn]

This adds a lot of clarification to the process used for selecting and rejecting proposals. This should assist users in writing proposals and should assist reviewers in applying clear and fair criteria to proposals.

All these considerations have been in use, and have been discussed among the core developers, but have not been formally verbalized yet.

[Calinou]

Thanks for taking the time to formalize this 🙂

I made some grammar suggestions below.

[Xrayez]

3. Can this proposal be implemented with an addon?

Evaluate whether it is possible for the proposal to be implemented in an addon. The likelihood of such a proposal being accepted depends on the amount of expressed community support, but if the proposal is a good candidate to be implemented in an addon while not receiving much feedback for some prolonged amount time, advise the person to propose the feature via Community Channels such as godot-ideas repository instead, closing the proposal.

The linked repo can help/close #91.

I've already re-implemented some core features via GDScript, so I don't think that "if can be implemented as addon" is enough to justify the decision to close such a proposal.

8. Can the feature be worked around in script with a few lines?

If the feature is intended to save users a few lines of code it is unlikely to be accepted, unless it solves a very common use case which can help to improve the overall usability of the engine (QoL features).

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Core developers have discretion to weigh the factors as they see fit.

🤷‍♂️

[clayjohn]

I've already re-implemented some core features via GDScript, so I don't think that "if can be implemented as addon" is enough to justify the decision to close such a proposal.

Only guideline 1 (also rule 1) can be used to justify closing a proposal on its own. All guidelines are factors to be weighed when making a decision.

[clayjohn]

@akien-mga This should be ready for final review/merging now.

Sorry for the long delay. I forgot about it completely. :P

[akien-mga]

Thanks!