Implement roundtrip-ready DisconnectedSpace archetype (#2833)

What the title says.

This does **not** migrate off of the legacy `DisconnectedSpace`, that's
for a future PR.

Part of #2791

### What

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested [demo.rerun.io](https://demo.rerun.io/pr/2833) (if
applicable)

- [PR Build Summary](https://build.rerun.io/pr/2833)
- [Docs
preview](https://rerun.io/preview/pr%3Acmc%2Froundtrippable_disconnected_transform/docs)
- [Examples
preview](https://rerun.io/preview/pr%3Acmc%2Froundtrippable_disconnected_transform/examples)

crates/re_space_view_spatial/src/parts/mod.rs

@@ -103,7 +103,7 @@ pub fn picking_id_from_instance_key(
 
 /// Process [`Color`] components using annotations and default colors.
 #[allow(dead_code)]
-pub fn process_colors_arch<'a, A: Archetype>(
+pub fn process_colors<'a, A: Archetype>(
     arch_view: &'a re_query::ArchetypeView<A>,
     ent_path: &'a EntityPath,
     annotation_infos: &'a [ResolvedAnnotationInfo],
@@ -122,7 +122,7 @@ pub fn process_colors_arch<'a, A: Archetype>(
 
 /// Process [`re_types::components::Radius`] components to [`re_renderer::Size`] using auto size
 /// where no radius is specified.
-pub fn process_radii_arch<'a, A: Archetype>(
+pub fn process_radii<'a, A: Archetype>(
     arch_view: &'a re_query::ArchetypeView<A>,
     ent_path: &EntityPath,
 ) -> Result<impl Iterator<Item = re_renderer::Size> + 'a, re_query::QueryError> {

crates/re_space_view_spatial/src/parts/points2d.rs

@@ -14,7 +14,7 @@ use crate::{
     contexts::{EntityDepthOffsets, SpatialSceneEntityContext},
     parts::{
         entity_iterator::process_archetype_views, load_keypoint_connections,
-        process_annotations_and_keypoints_arch, process_colors_arch, process_radii_arch, UiLabel,
+        process_annotations_and_keypoints_arch, process_colors, process_radii, UiLabel,
         UiLabelTarget,
     },
     view_kind::SpatialSpaceViewKind,
@@ -82,13 +82,13 @@ impl Points2DPart {
             Points2D,
         >(query, arch_view, &ent_context.annotations)?;
 
-        let colors = process_colors_arch(arch_view, ent_path, &annotation_infos)?;
-        let radii = process_radii_arch(arch_view, ent_path)?;
+        let colors = process_colors(arch_view, ent_path, &annotation_infos)?;
+        let radii = process_radii(arch_view, ent_path)?;
 
         if arch_view.num_instances() <= self.max_labels {
             // Max labels is small enough that we can afford iterating on the colors again.
             let colors =
-                process_colors_arch(arch_view, ent_path, &annotation_infos)?.collect::<Vec<_>>();
+                process_colors(arch_view, ent_path, &annotation_infos)?.collect::<Vec<_>>();
 
             let instance_path_hashes_for_picking = {
                 re_tracing::profile_scope!("instance_hashes");

crates/re_space_view_spatial/src/parts/points3d.rs

@@ -14,7 +14,7 @@ use crate::{
     contexts::{EntityDepthOffsets, SpatialSceneEntityContext},
     parts::{
         entity_iterator::process_archetype_views, load_keypoint_connections,
-        process_annotations_and_keypoints_arch, process_colors_arch, process_radii_arch, UiLabel,
+        process_annotations_and_keypoints_arch, process_colors, process_radii, UiLabel,
         UiLabelTarget,
     },
     view_kind::SpatialSpaceViewKind,
@@ -85,13 +85,13 @@ impl Points3DPart {
             Points3D,
         >(query, arch_view, &ent_context.annotations)?;
 
-        let colors = process_colors_arch(arch_view, ent_path, &annotation_infos)?;
-        let radii = process_radii_arch(arch_view, ent_path)?;
+        let colors = process_colors(arch_view, ent_path, &annotation_infos)?;
+        let radii = process_radii(arch_view, ent_path)?;
 
         if arch_view.num_instances() <= self.max_labels {
             // Max labels is small enough that we can afford iterating on the colors again.
             let colors =
-                process_colors_arch(arch_view, ent_path, &annotation_infos)?.collect::<Vec<_>>();
+                process_colors(arch_view, ent_path, &annotation_infos)?.collect::<Vec<_>>();
 
             let instance_path_hashes_for_picking = {
                 re_tracing::profile_scope!("instance_hashes");

crates/re_types/definitions/rerun/archetypes.fbs

@@ -1,3 +1,4 @@
+include "./archetypes/disconnected_space.fbs";
 include "./archetypes/points2d.fbs";
 include "./archetypes/points3d.fbs";
 include "./archetypes/transform3d.fbs";

crates/re_types/definitions/rerun/archetypes/disconnected_space.fbs

@@ -0,0 +1,32 @@
+include "fbs/attributes.fbs";
+
+include "rerun/datatypes.fbs";
+include "rerun/components.fbs";
+
+namespace rerun.archetypes;
+
+/// Specifies that the entity path at which this is logged is disconnected from its parent.
+///
+/// This is useful for specifying that a subgraph is independent of the rest of the scene.
+///
+/// If a transform or pinhole is logged on the same path, this archetype's components
+/// will be ignored.
+///
+/// \py Example
+/// \py -------
+/// \py
+/// \py ```python
+/// \py \include:../../../../../docs/code-examples/disconnected_space_v2.py
+/// \py ```
+///
+/// \rs ## Example
+/// \rs
+/// \rs ```ignore
+/// \rs \include:../../../../../docs/code-examples/disconnected_space_v2.rs
+/// \rs ```
+table DisconnectedSpace (
+  "attr.rust.derive": "Copy, PartialEq, Eq",
+  order: 100
+) {
+  disconnected_space: rerun.components.DisconnectedSpace ("attr.rerun.component_required", required, order: 1000);
+}

crates/re_types/definitions/rerun/components.fbs

@@ -1,5 +1,6 @@
 include "./components/class_id.fbs";
 include "./components/color.fbs";
+include "./components/disconnected_space.fbs";
 include "./components/draw_order.fbs";
 include "./components/instance_key.fbs";
 include "./components/keypoint_id.fbs";

crates/re_types/definitions/rerun/components/class_id.fbs

@@ -8,16 +8,16 @@ namespace rerun.components;
 
 // ---
 
-// TODO(#2801): serde should be cfg_attr gated here
-
 /// A 16-bit ID representing a type of semantic class.
 ///
 /// \rs Used to look up a `crate::components::ClassDescription` within the `crate::components::AnnotationContext`.
 struct ClassId (
   "attr.python.aliases": "int",
   "attr.python.array_aliases": "int, npt.NDArray[np.uint8], npt.NDArray[np.uint16], npt.NDArray[np.uint32], npt.NDArray[np.uint64]",
   "attr.rerun.legacy_fqname": "rerun.class_id",
-  "attr.rust.derive": "Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash, ::serde::Serialize, ::serde::Deserialize",
+  "attr.rust.derive": "Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash",
+  "attr.rust.custom_clause":
+    'cfg_attr(feature = "serde", derive(::serde::Serialize, ::serde::Deserialize))',
   order: 100
 ) {
   id: ushort (order: 100);

crates/re_types/definitions/rerun/components/disconnected_space.fbs

@@ -0,0 +1,25 @@
+include "arrow/attributes.fbs";
+include "python/attributes.fbs";
+include "rust/attributes.fbs";
+
+include "rerun/datatypes.fbs";
+include "rerun/attributes.fbs";
+
+namespace rerun.components;
+
+// ---
+
+/// Specifies that the entity path at which this is logged is disconnected from its parent.
+///
+/// This is useful for specifying that a subgraph is independent of the rest of the scene.
+///
+/// If a transform or pinhole is logged on the same path, this component will be ignored.
+struct DisconnectedSpace (
+  "attr.python.aliases": "bool",
+  "attr.python.array_aliases": "bool, npt.NDArray[np.bool_]",
+  "attr.rerun.legacy_fqname": "rerun.disconnected_space",
+  "attr.rust.derive": "Copy, PartialEq, Eq",
+  order: 100
+) {
+  is_disconnected: bool (order: 100);
+}

crates/re_types/definitions/rerun/components/keypoint_id.fbs

@@ -8,8 +8,6 @@ namespace rerun.components;
 
 // ---
 
-// TODO(#2801): serde should be cfg_attr gated here
-
 /// A 16-bit ID representing a type of semantic keypoint within a class.
 ///
 /// \py `KeypointId`s are only meaningful within the context of a [`rerun.components.ClassDescription`][].
@@ -24,7 +22,9 @@ struct KeypointId (
   "attr.python.aliases": "float",
   "attr.python.array_aliases": "float, npt.NDArray[np.uint8], npt.NDArray[np.uint16], npt.NDArray[np.uint32]",
   "attr.rerun.legacy_fqname": "rerun.keypoint_id",
-  "attr.rust.derive": "Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash, ::serde::Serialize, ::serde::Deserialize",
+  "attr.rust.derive": "Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash",
+  "attr.rust.custom_clause":
+    'cfg_attr(feature = "serde", derive(::serde::Serialize, ::serde::Deserialize))',
   order: 200
 ) {
   id: ushort (order: 100);