Nodes: add descriptions for why links are invalid #121976

Jacques Lucke · 2024-05-19T14:24:49+02:00

Jacques Lucke commented

2024-05-19 14:24:49 +02:00

Blender shows invalid links in red in the node editor. However, it's not always obvious why some links don't work, especially for beginners. This patch adds additional information for every invalid link on the node that it links to.

The following error messages are added:

Invalid link because of missing implicit conversions.
Link cycle in node tree.
A link from a field to a socket that does not support fields.
Using the same menu on multiple Menu Switch nodes.

Currently, there are some per tree-type special cases in the link validation code. In the future, this should be moved to tree type specific callbacks.

Blender shows invalid links in red in the node editor. However, it's not always obvious why some links don't work, especially for beginners. This patch adds additional information for every invalid link on the node that it links to. The following error messages are added: * Invalid link because of missing implicit conversions. * Link cycle in node tree. * A link from a field to a socket that does not support fields. * Using the same menu on multiple Menu Switch nodes. Currently, there are some per tree-type special cases in the link validation code. In the future, this should be moved to tree type specific callbacks. ![image](/attachments/2e25d719-8b1a-4801-82d5-675a73edaf3f)

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👍 2 🚀 5

Jacques Lucke added 2 commits 2024-05-19 14:24:57 +02:00

initial invalid link info 4f31fe7680

add menu error message 9fe0288c1e

Jacques Lucke added 1 commit 2024-05-19 14:30:35 +02:00

add cyclic node tree info 328d642244

Jacques Lucke requested review from Simon Thommes 2024-05-19 14:34:29 +02:00

Jacques Lucke requested review from Hans Goudey 2024-05-19 14:34:29 +02:00

Jacques Lucke added 1 commit 2024-05-19 14:43:23 +02:00

Merge branch 'main' into invalid-links-info be7581e0fe

Hans Goudey reviewed 2024-05-20 01:46:32 +02:00

Hans Goudey left a comment

Overall +1, especially for the hint about node groups with the menu socket, that will probably help people.

source/blender/editors/space_node/node_draw.cc Outdated

						
				@ -2987,0 +3016,4 @@

				          continue;

				        }

				      }

				      if (tree.type == NTREE_GEOMETRY) {

Hans Goudey commented

2024-05-20 01:46:02 +02:00

I guess I bring this up a lot, but I don't really like how these tree types and socket types are hardcoded in code that could/should be more general. For example, another way for this to work would be more closely aligned with the existing code that makes links red in the UI. Error messages could be assigned at that point and drawn on the "to" node. That's basically extending the existing generic system.

Jacques Lucke commented

2024-05-20 19:33:23 +02:00

I moved the error messages closer to the code that makes the links invalid, that's a good idea. There is still some special case handling for geometry nodes going on there right now, but I think it's good enough now, better than having it in drawing code.

JacquesLucke marked this conversation as resolved

Jacques Lucke added 2 commits 2024-05-20 19:32:34 +02:00

Merge branch 'main' into invalid-links-info f736153eb4

move invalid link errors to tree update code 7e1b290da1

Hans Goudey approved these changes 2024-05-20 19:48:54 +02:00

Hans Goudey left a comment

I'm okay with this now, thanks. I think the next step is to make a slightly more powerful version of validate_link that returns an optional error message for why the link isn't valid. That seems like the right way to make the behavior generic. If you don't mind, could you mention that as a TODO in the code or the commit message?

I'm okay with this now, thanks. I think the next step is to make a slightly more powerful version of `validate_link` that returns an optional error message for why the link isn't valid. That seems like the right way to make the behavior generic. If you don't mind, could you mention that as a TODO in the code or the commit message?

Erindale commented

2024-05-21 17:08:23 +02:00

First-time contributor

This is looking good! Definitely makes these learning moments more valuable

Iliya Katushenock commented

2024-05-22 12:49:58 +02:00

+1 to remove NodeLinkError and just call std::optional<StringRef> bNodeTreeType::validate_link(...) const in draw code.

+1 to remove `NodeLinkError` and just call `std::optional<StringRef> bNodeTreeType::validate_link(...) const` in draw code.

Jacques Lucke commented

2024-05-22 16:04:42 +02:00

@mod_moder The error message is generated sometimes and thus can't just be stored in a StringRef. Also it's not really worth optimizing this, because there aren't many link errors overall.

@mod_moder The error message is generated sometimes and thus can't just be stored in a `StringRef`. Also it's not really worth optimizing this, because there aren't many link errors overall.

Iliya Katushenock commented

2024-05-22 16:08:05 +02:00

Total number of invalid cases not so many to do not just store them strings in some static array\

Simon Thommes requested changes 2024-05-22 19:55:19 +02:00

Dismissed

Simon Thommes left a comment

Looks great overall!

The overlay should ideally be shown only once with multiple conflicts per node and the tooltip should show a de-duplicated list.

Looks great overall! The overlay should ideally be shown only once with multiple conflicts per node and the tooltip should show a de-duplicated list. ![image](/attachments/93d036a1-d4e9-48b9-8d4e-097388c480c4)

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32 KiB

Jacques Lucke added 2 commits 2024-05-23 13:46:55 +02:00

Merge branch 'main' into invalid-links-info d028c03f90

batch multiple invalid links into one tooltip 5067bea034

Jacques Lucke requested review from Simon Thommes 2024-05-23 13:47:28 +02:00

Simon Thommes approved these changes 2024-05-23 14:22:28 +02:00

Simon Thommes left a comment

Looks good to me now!

Jacques Lucke merged commit 399f6a1c60 into main

2024-05-23 14:31:28 +02:00

Jacques Lucke referenced this issue from a commit