Got a crash when testing, but probably caused by D12553: Geometry Nodes: Implicit Position input in Set Position node..

To reproduce:

• Add a curve spiral node and connect it to the output
• Drop a set position node on top of the link

1. I find strange to have a node that changes its socket from circle to diamond. I wonder if the solution from the mockup (the semi-circle-semi-diamond) works better as the initial shape.

2. I managed to get a memleak: "Error: Not freed memory blocks: 2, total unfreed memory 0.000000 MB"

3. (low priority) Attribute sockets should show as diamonds in the Output lists

4. In my setup I would expect the Greater Than node to have a diamond output (and also the Separate XYZ).

5. The statistics node is not updated yet.

Value input node output socket should be plain simple circle:

I think that it may still make sense to have the socket to be a full circle when the circle is connected. I find it strange that we change the hybrid socket when we connect a diamond, but not when we connect a circle.

An input is a circle to indicate that this input is required to be data instead of a field. Just because data is connected, does not mean that data is suddenly required on the input.
How about we use four socket shapes:

• Circle: This is data.
• Diamond: This is a field.
• Circle with dot: This is data, but is allowed to become a field.
• Diamond with dot: This is a field, but is allowed to become data.

1. Disconnect the output from "Greater Than" to the Set Position node.
2. Issue #1 both outputs noodles from Position are red. I don't think either of them should be red, but if they are, there shouldn't be both, only the lower one.
3. I can't make them go back to normal. No amount of reconnecting, save, load, ... can bring them back to normal.

Side bugs:

• I would expect the "Separate XYZ" to output Fields if a field is connected to its input.
• Same for "Greater Than"

Update: you don't even need to disconnect the output, just by trying to disconnect and cancelling it, already brings in the broken state.

This looks good to me. I will commit it with a few very small tweaks, mostly to comments.

There are a couple points where some brief comments would make understanding the code much easier, and I didn't feel like I could write a great one.

• dummy_socket_state
• propagate_field_status_from_left_to_right
• propagate_data_requirements_from_right_to_left

I see my comment had several inline comments attached to it, I totally forgot about them. They're either already done, not finished, or not actionable, so they can just be disregarded.