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Bifrost Combustion & Cache node

Message 1 of 7
1398 Views, 6 Replies

Bifrost Combustion & Cache node


I am trying to use the file_cache node with my combustion network.


I got an Error with complex traces (see the picture for the full explanation)


Any ideas ?


bifrost cache.jpg

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Message 2 of 7
in reply to: moiamy

You are trying to output an object of type array<Amino::Object> , while the output port of your graph has a type Amino::Object . In other words, you are trying to output an array into a single value port.


Judging from the output port name of your graph, you created the output port by connecting the output of simulate_aero, and then you've tried to plug the output of file_cache, which has a different type. If you pay attention, you can see that the output port out_objects on file_cache has a little hat-shaped icon. This means that this is an array and not a single value.


What you can do is just create another output port on your graph, or change the type of your current output port. 


Because this is the top level of your graph, the auto type feature on ports is disabled, so you have to be a little bit careful about it.

Maxime Jeanmougin - Technical Artist

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Message 3 of 7
in reply to: mjcg91

Thanks Mjcg91 for the clue.


Nevertheless when I try a "write_OpenVDB" node with consistent input/output, I got the same error.


bifrost cache 2.jpg

Message 4 of 7
in reply to: moiamy

Actually you were right. Just needed to connect the right output node


(Still I don't get why the vdb node doesn't work)


bifrost cache 3.jpg



Message 5 of 7
in reply to: moiamy

This is the same problem. Try connecting it to the second output and it will work.


Ian if you read this, maybe it should be better if the port icon doesn't change when incompatible. In case like this, if the port was still showing its original type, it would help new users to debug issues like this. 

Maxime Jeanmougin - Technical Artist

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Message 6 of 7
in reply to: mjcg91

I agree that the port appearance should not change in this case. It would be even better if auto-ports were possible on the output node, but having the correct affordance as you suggest is always a good idea. I've logged an improvement request. Thanks!

Ian Hooper
UX Architect
Message 7 of 7

Also, I am not sure connecting an array to the output node works very well with the bifShape. I would recommend using first_in_array or get_from_array to get the appropriate element from your file_cache node or write_OpenVDB instead of connecting the array out-port directly the the output node.


I.e. ----> write_OpenVDB -----> first_in_array -----> output

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