Derive pushed index levels per input and pop them when lifting requirements

node-graph/graph-craft/src/proto.rs

@@ -523,10 +523,13 @@ impl ProtoNetwork {
 		};
 
 		// Compute the dependencies for each branch and combine all of them
-		for &node in &inputs {
+		let pushed_levels = self.nodes[node_index].1.context_features.pushed_levels.clone();
+		for (input, &node) in inputs.iter().enumerate() {
 			let branch = self.find_context_dependencies(node);
 
-			combined_deps |= &branch.0;
+			let mut lifted = branch.0.clone();
+			lifted.index_levels = lifted.index_levels.popped(pushed_levels.get(input).copied().unwrap_or(0));
+			combined_deps |= &lifted;
 			branch_dependencies.push(branch);
 		}
 		let mut new_deps = combined_deps.clone();

node-graph/libraries/core-types/src/context.rs

@@ -57,10 +57,9 @@ pub trait ExtractIndices {
 	}
 }
 
-/// `LEVEL` is the level of the index chain a node reads, counted outwards from
+/// `LEVEL` is the index-chain level a node reads, counted outwards from the
-/// the innermost. Declaring it narrows the cache key to that level, and reading
+/// innermost; only declared levels survive in the cache key. Repeat the bound
-/// through `index` keeps the declaration and the read from drifting apart.
+/// to declare several, spelling the level at each `index` call.
-/// Repeat the bound to declare several, then spell the level at each read.
 pub trait ExtractIndex<const LEVEL: u8 = 0>: ExtractIndices {
 	fn index(&self) -> u64 {
 		self.try_index().and_then(|mut levels| levels.nth(LEVEL as usize)).unwrap_or(0) as u64
@@ -245,6 +244,17 @@ impl IndexLevels {
 		self.0 == u32::MAX
 	}
 
+	/// The same requirement seen from outside `levels` pushed levels. An
+	/// all-levels mask stays saturated, since its reader's level is not known at
+	/// compile time.
+	pub const fn popped(self, levels: u8) -> Self {
+		match self.0 {
+			u32::MAX => self,
+			_ if levels as u32 >= u32::BITS => Self(0),
+			mask => Self(mask >> levels),
+		}
+	}
+
 	/// Levels at or past `u32::BITS` are only readable through the all-levels
 	/// sentinel, so they count as declared whenever the mask is saturated.
 	pub const fn contains_level(self, level: usize) -> bool {
@@ -319,6 +329,9 @@ pub struct ContextDependencies {
 	/// written before the field existed default to the whole chain.
 	#[cfg_attr(feature = "serde", serde(default = "IndexLevels::innermost"))]
 	pub index_levels: IndexLevels,
+	/// Index levels pushed per input, in input order; a missing entry is 0.
+	#[cfg_attr(feature = "serde", serde(default))]
+	pub pushed_levels: Vec<u8>,
 	#[cfg_attr(feature = "serde", serde(default, deserialize_with = "deserialize_sorted_sources"))]
 	sources: Vec<SourceId>,
 }
@@ -333,6 +346,7 @@ impl ContextDependencies {
 			extract,
 			inject,
 			index_levels,
+			pushed_levels: Vec::new(),
 			sources: Vec::new(),
 		}
 	}
@@ -342,6 +356,11 @@ impl ContextDependencies {
 		self
 	}
 
+	pub fn with_pushed_levels(mut self, pushed_levels: Vec<u8>) -> Self {
+		self.pushed_levels = pushed_levels;
+		self
+	}
+
 	pub fn sources(&self) -> &[SourceId] {
 		&self.sources
 	}
@@ -496,6 +515,7 @@ impl From<&[ContextFeature]> for ContextDependencies {
 			extract,
 			inject,
 			index_levels,
+			pushed_levels: Vec::new(),
 			sources: Vec::new(),
 		}
 	}

node-graph/libraries/core-types/src/registry.rs

@@ -29,6 +29,8 @@ pub struct NodeMetadata {
 pub struct FieldMetadata {
 	pub name: &'static str,
 	pub description: &'static str,
+	/// Index levels the node pushes when evaluating this input.
+	pub pushed_levels: u8,
 	pub hidden: bool,
 	pub exposed: bool,
 	pub widget_override: RegistryWidgetOverride,

node-graph/node-macro/src/codegen.rs

@@ -178,6 +178,17 @@ pub(crate) fn generate_node_code(crate_ident: &CrateIdent, parsed: &ParsedNodeFn
 
 	let input_descriptions: Vec<_> = regular_fields.iter().map(|f| &f.description).collect();
 
+	let subject_depth = node.inputs.iter().find(|input| input.subject).map_or(0, |input| input.shape.depth);
+	let pushed_levels = (node.output.shape.depth as i8 - subject_depth as i8).max(0) as u8;
+	let field_pushed_levels: Vec<u8> = regular_fields
+		.iter()
+		.map(|field| match &field.ty {
+			ParsedFieldType::Regular(RegularParsedField { list_levels, .. }) if *list_levels > 0 => *list_levels as u8,
+			ParsedFieldType::Node(_) => pushed_levels,
+			_ => 0,
+		})
+		.collect();
+
 	// Generate struct fields: data fields (concrete types) + regular fields (generic types)
 	let data_field_defs = data_fields.iter().map(|field| {
 		let name = &field.pat_ident.ident;
@@ -633,6 +644,7 @@ pub(crate) fn generate_node_code(crate_ident: &CrateIdent, parsed: &ParsedNodeFn
 								name: #input_names,
 								widget_override: #widget_override,
 								description: #input_descriptions,
+								pushed_levels: #field_pushed_levels,
 								hidden: #input_hidden,
 								exposed: #exposed,
 								value_source: #value_sources,

node-graph/nodes/path-bool/src/lib.rs

@@ -98,7 +98,7 @@ fn boolean_core<'e>(
 /// Combines the geometric forms of one or more closed paths into a new vector path that results from cutting or joining the paths by the chosen method.
 #[node_macro::node(category("Vector: Modifier"), memoize)]
 fn boolean_operation<'e>(
-	ctx: impl Ctx + ExtractArena<'e> + core_types::ExtractIndex + core_types::InjectIndex + Copy,
+	ctx: impl Ctx + ExtractArena<'e> + core_types::InjectIndex + Copy,
 	/// The wire of vector paths to perform the boolean operation on. Nested groups are automatically flattened.
 	content: IList<Graphic>,
 	/// Which boolean operation to perform on the paths.
@@ -134,7 +134,7 @@ fn boolean_operation<'e>(
 /// The boolean operation over a plain vector level, as [`boolean_operation`].
 #[node_macro::node(category(""))]
 fn boolean_operation_vector<'e>(
-	ctx: impl Ctx + ExtractArena<'e> + core_types::ExtractIndex + core_types::InjectIndex + Copy,
+	ctx: impl Ctx + ExtractArena<'e> + core_types::InjectIndex + Copy,
 	content: IList<Vector>,
 	operation: BooleanOperation,
 ) -> Result<

node-graph/nodes/vector/src/vector_nodes.rs

@@ -237,9 +237,8 @@ fn assign_colors_graphic<'e>(
 	Ok((element, transform, layer_path))
 }
 
-/// Where each lane's colors start in the level's flattened vector run, so the
+/// Where each lane's colors start in the level's flattened vector run, valid
-/// level is counted once per evaluation rather than once per lane. `offsets`
+/// for one key and generation. `offsets` holds one entry per lane plus the total.
-/// holds one entry per lane plus the total.
 #[derive(Debug)]
 pub struct LaneOffsets {
 	key: u64,

node-graph/preprocessor/src/lib.rs

@@ -205,7 +205,7 @@ impl Preprocessor {
 				implementation: DocumentNodeImplementation::ProtoNode(id.clone()),
 				visible: true,
 				skip_deduplication: false,
-				context_features: ContextDependencies::from(metadata.context_features.as_slice()),
+				context_features: ContextDependencies::from(metadata.context_features.as_slice()).with_pushed_levels(metadata.fields.iter().map(|field| field.pushed_levels).collect()),
 				..Default::default()
 			};
 
@@ -256,7 +256,7 @@ impl Preprocessor {
 					call_argument: node_io.call_argument.clone(),
 					implementation: DocumentNodeImplementation::ProtoNode(id.clone()),
 					visible: true,
-					context_features: ContextDependencies::from(metadata.context_features.as_slice()),
+					context_features: ContextDependencies::from(metadata.context_features.as_slice()).with_pushed_levels(metadata.fields.iter().map(|field| field.pushed_levels).collect()),
 					..Default::default()
 				};
 				inject_scopes.insert(id.clone(), (template, node_io.return_value.clone()));