vvvv-custom-nodes

Name: vvvv-custom-nodes
Author: tebjan

65installs5forks

How to install vvvv-custom-nodes?

tebjan/vvvv-skills/vvvv-custom-nodes

$npx -y skills add tebjan/vvvv-skills --skill vvvv-custom-nodes

Installs into the current project.

Summary

Helps write C# node classes for vvvv gamma — the [ProcessNode] lifecycle pattern, Update() method, out parameters, pin configuration, change detection, stateless operation nodes, the public-API import model, and service consumption via NodeContext (IFrameClock, Game access, loggi

Files · 1

View on GitHub

SKILL.md

1	# Writing Custom Nodes for vvvv gamma
2
3	## What `[ProcessNode]` actually does (and what it does NOT do)
4
5	Important reality check. vvvv imports every `public` class, struct, enum, method, and property from the assembly's configured namespaces — `[ProcessNode]` does NOT control whether a class becomes a node. A plain `public class Foo { public int Bar(int x) => x; }` will appear in the node browser exactly the same way as one decorated with `[ProcessNode]`. The attribute affects how the runtime treats the class, not whether it gets imported.
6
7	What `[ProcessNode]` DOES:
8
9	- Tells vvvv "this is a stateful node — keep ONE instance alive per node in the patch and call its `Update()` method each frame".
10	- Lets you set `Name = "..."` (rename for the node browser), `Category = "..."` (override the assembly's category), and `HasStateOutput = true` (expose the instance as an output pin).
11	- Engages live reload, `IDisposable` cleanup, and the `NodeContext` constructor injection.
12
13	What `[ProcessNode]` does NOT do:
14
15	- It does NOT make a class visible to vvvv. Visibility comes from the C# `public` access modifier plus an `[assembly: ImportAsIs/ImportNamespace/ImportType]` attribute. See vvvv-node-libraries for the import rules.
16	- It does NOT hide internal helpers. If a helper is `public`, it's a node — period. Use `internal` to hide.
17	- It does NOT change pin generation. Pin generation is driven by the `Update()` method signature for `[ProcessNode]` classes, and by public method/property signatures for non-`[ProcessNode]` classes.
18
19	When to use `[ProcessNode]`: the class needs frame-by-frame updates, persistent state between frames, or `IDisposable` cleanup. When to skip `[ProcessNode]`: stateless utility classes, value types, static helper methods — leaving the attribute off avoids the per-frame `Update()` ceremony, and the public methods become operation nodes automatically.
20
21	## ProcessNode Pattern — The Core Pattern
22
23	The canonical stateful C# node in vvvv gamma:
24
25	```csharp
26	[ProcessNode]
27	public class MyTransform : IDisposable
28	{
29	private float _lastInput;
30	private float _cachedResult;
31
32	/// <summary>
33	/// Transforms input values with caching.
34	/// </summary>
35	public void Update(
36	out float result, // OUT parameters FIRST
37	out string error, // More out params
38	float input = 0f, // Value inputs with defaults AFTER
39	bool reset = false)
40	{
41	error = null;
42
43	if (input != _lastInput \|\| reset)
44	{
45	_cachedResult = ExpensiveComputation(input);
46	_lastInput = input;
47	}
48
49	result = _cachedResult; // ALWAYS output cached data
50	}
51
52	public void Dispose() { /* cleanup */ }
53	}
54	```
55
56	Prerequisite: vvvv only sees a `[ProcessNode]` class (or any other public class) if its namespace is covered by an assembly-level import attribute — `[assembly: ImportAsIs]`, `[assembly: ImportNamespace]`, or `[assembly: ImportType]` for that specific class. Without one of those, the assembly's public API is invisible to the node browser entirely. Projects scaffolded by vvvv include `[assembly: ImportAsIs]` automatically. For multi-namespace libraries or hand-picked node lists, see vvvv-node-libraries — `ImportAsIs` is `AllowMultiple = false`, so you'll reach for `ImportNamespace` (multi-use) or `ImportType` (per-type) when one root attribute isn't enough.
57
58	### Non-Negotiable Rules
59
60	1. `[ProcessNode]` attribute on every stateful node class
61	2. No "Node" in the vvvv-visible name — everything in vvvv is already a node, so "Node" suffix is redundant
62	3. `out` parameters FIRST, value inputs with defaults AFTER
63	4. XML comments on class and Update method (shown as tooltip in vvvv)
64	5. ZERO allocations in Update — no `new`, no LINQ, cache everything
65	6. Change detection — only recompute when inputs actually change
66	7. Always output latest data — even when no work is done, output cached result
67	8. No unnecessary public members — data flows through Update in/out params only
68	9. `IDisposable` for any node holding native/unmanaged resources
69
70	### Live Reload Behavior
71
72	When the .v

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Type

vvvv-custom-nodes

65installs5forks

View on GitHub

How to install vvvv-custom-nodes?

tebjan/vvvv-skills/vvvv-custom-nodes

$npx -y skills add tebjan/vvvv-skills --skill vvvv-custom-nodes

Installs into the current project.

Summary

Files · 1

View on GitHub

SKILL.md

1	# Writing Custom Nodes for vvvv gamma
2
3	## What `[ProcessNode]` actually does (and what it does NOT do)
4
5	Important reality check. vvvv imports every `public` class, struct, enum, method, and property from the assembly's configured namespaces — `[ProcessNode]` does NOT control whether a class becomes a node. A plain `public class Foo { public int Bar(int x) => x; }` will appear in the node browser exactly the same way as one decorated with `[ProcessNode]`. The attribute affects how the runtime treats the class, not whether it gets imported.
6
7	What `[ProcessNode]` DOES:
8
9	- Tells vvvv "this is a stateful node — keep ONE instance alive per node in the patch and call its `Update()` method each frame".
10	- Lets you set `Name = "..."` (rename for the node browser), `Category = "..."` (override the assembly's category), and `HasStateOutput = true` (expose the instance as an output pin).
11	- Engages live reload, `IDisposable` cleanup, and the `NodeContext` constructor injection.
12
13	What `[ProcessNode]` does NOT do:
14
15	- It does NOT make a class visible to vvvv. Visibility comes from the C# `public` access modifier plus an `[assembly: ImportAsIs/ImportNamespace/ImportType]` attribute. See vvvv-node-libraries for the import rules.
16	- It does NOT hide internal helpers. If a helper is `public`, it's a node — period. Use `internal` to hide.
17	- It does NOT change pin generation. Pin generation is driven by the `Update()` method signature for `[ProcessNode]` classes, and by public method/property signatures for non-`[ProcessNode]` classes.
18
19	When to use `[ProcessNode]`: the class needs frame-by-frame updates, persistent state between frames, or `IDisposable` cleanup. When to skip `[ProcessNode]`: stateless utility classes, value types, static helper methods — leaving the attribute off avoids the per-frame `Update()` ceremony, and the public methods become operation nodes automatically.
20
21	## ProcessNode Pattern — The Core Pattern
22
23	The canonical stateful C# node in vvvv gamma:
24
25	```csharp
26	[ProcessNode]
27	public class MyTransform : IDisposable
28	{
29	private float _lastInput;
30	private float _cachedResult;
31
32	/// <summary>
33	/// Transforms input values with caching.
34	/// </summary>
35	public void Update(
36	out float result, // OUT parameters FIRST
37	out string error, // More out params
38	float input = 0f, // Value inputs with defaults AFTER
39	bool reset = false)
40	{
41	error = null;
42
43	if (input != _lastInput \|\| reset)
44	{
45	_cachedResult = ExpensiveComputation(input);
46	_lastInput = input;
47	}
48
49	result = _cachedResult; // ALWAYS output cached data
50	}
51
52	public void Dispose() { /* cleanup */ }
53	}
54	```
55
56	Prerequisite: vvvv only sees a `[ProcessNode]` class (or any other public class) if its namespace is covered by an assembly-level import attribute — `[assembly: ImportAsIs]`, `[assembly: ImportNamespace]`, or `[assembly: ImportType]` for that specific class. Without one of those, the assembly's public API is invisible to the node browser entirely. Projects scaffolded by vvvv include `[assembly: ImportAsIs]` automatically. For multi-namespace libraries or hand-picked node lists, see vvvv-node-libraries — `ImportAsIs` is `AllowMultiple = false`, so you'll reach for `ImportNamespace` (multi-use) or `ImportType` (per-type) when one root attribute isn't enough.
57
58	### Non-Negotiable Rules
59
60	1. `[ProcessNode]` attribute on every stateful node class
61	2. No "Node" in the vvvv-visible name — everything in vvvv is already a node, so "Node" suffix is redundant
62	3. `out` parameters FIRST, value inputs with defaults AFTER
63	4. XML comments on class and Update method (shown as tooltip in vvvv)
64	5. ZERO allocations in Update — no `new`, no LINQ, cache everything
65	6. Change detection — only recompute when inputs actually change
66	7. Always output latest data — even when no work is done, output cached result
67	8. No unnecessary public members — data flows through Update in/out params only
68	9. `IDisposable` for any node holding native/unmanaged resources
69
70	### Live Reload Behavior
71
72	When the .v

People who liked this also viewed

6 picks

Type