Codegen for space view python blueprint classes (#6100)

### What

* Fixes #6081

Extends our codegen to accept a fourth object type, space views (in
addition to datatypes/components/archetypes). Meaning we can do special
codegen for space views now, making it easy to set them up consistently
and define what properties a space view can be constructed from.
Building up on the previous PR that exposed background3d color, this
generates almost identical code now.

Doesn't add yet any new view properties - this is going to happen in a
follow-up PR since it requires getting a few more things serializable
and subsequently also testing.

### 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 the web demo (if applicable):
* Using examples from latest `main` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/6100?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/6100?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG
* [x] If applicable, add a new check to the [release
checklist](https://github.com/rerun-io/rerun/blob/main/tests/python/release_checklist)!

- [PR Build Summary](https://build.rerun.io/pr/6100)
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To run all checks from `main`, comment on the PR with `@rerun-bot
full-check`.

crates/re_types/definitions/python/attributes.fbs

@@ -1,8 +1,6 @@
 namespace python.attributes;
 
-/// Defines the type aliases for a component, e.g. the types that make up `ComponentLike`.
-///
-/// Only applies to structs/unions that are components.
+/// Defines the type aliases for a component or view property archetype, e.g. the types that make up `ComponentLike`.
 attribute "attr.python.aliases";
 
 /// Defines the array type aliases for a component, e.g. the types that make up `ComponentArrayLike`.

crates/re_types/definitions/rerun/attributes.fbs

@@ -25,11 +25,16 @@ attribute "attr.rerun.component_optional";
 /// For lists this will apply to the inner element.
 attribute "attr.rerun.override_type";
 
-/// Set the scope of the type
+/// Set the scope of the type.
 ///
 /// This is used for example to scope blueprint types.
 attribute "attr.rerun.scope";
 
+/// Specifies the type identifier for a space view type.
+///
+/// This is mandatory for space view types.
+attribute "attr.rerun.view_identifier";
+
 /// Marks something as deprecated followed by a (mandatory!) migration note.
 ///
 /// If specified on an object (struct/enum/union), it becomes deprecated such

crates/re_types/definitions/rerun/blueprint.fbs

@@ -32,3 +32,11 @@ include "./blueprint/archetypes/viewport_blueprint.fbs";
 
 include "./blueprint/archetypes/plot_legend.fbs";
 include "./blueprint/archetypes/scalar_axis.fbs";
+
+include "./blueprint/views/bar_chart.fbs";
+include "./blueprint/views/spatial2d.fbs";
+include "./blueprint/views/spatial3d.fbs";
+include "./blueprint/views/tensor.fbs";
+include "./blueprint/views/text_document.fbs";
+include "./blueprint/views/text_log.fbs";
+include "./blueprint/views/time_series.fbs";

crates/re_types/definitions/rerun/blueprint/archetypes/background_3d.fbs

@@ -12,7 +12,8 @@ namespace rerun.blueprint.archetypes;
 
 /// Configuration for the background of the 3D space view.
 table Background3D (
-    "attr.rerun.scope": "blueprint"
+    "attr.rerun.scope": "blueprint",
+    "attr.python.aliases": "datatypes.Rgba32Like, blueprint_components.Background3DKindLike"
 ) {
     // --- Required ---
 

crates/re_types/definitions/rerun/blueprint/views/bar_chart.fbs

@@ -0,0 +1,9 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A bar chart view.
+table BarChartView (
+    "attr.rerun.view_identifier": "BarChart"
+) {
+}

crates/re_types/definitions/rerun/blueprint/views/spatial2d.fbs

@@ -0,0 +1,9 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A Spatial 2D view.
+table Spatial2DView (
+    "attr.rerun.view_identifier": "2D"
+) {
+}

crates/re_types/definitions/rerun/blueprint/views/spatial3d.fbs

@@ -0,0 +1,11 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A Spatial 3D view.
+table Spatial3DView (
+    "attr.rerun.view_identifier": "3D"
+) {
+    /// Configuration for the background of the 3D space view.
+    background: rerun.blueprint.archetypes.Background3D (order: 1000);
+}

crates/re_types/definitions/rerun/blueprint/views/tensor.fbs

@@ -0,0 +1,9 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A tensor view.
+table TensorView (
+    "attr.rerun.view_identifier": "Tensor"
+) {
+}

crates/re_types/definitions/rerun/blueprint/views/text_document.fbs

@@ -0,0 +1,9 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A text document view.
+table TextDocumentView (
+    "attr.rerun.view_identifier": "TextDocument"
+) {
+}

crates/re_types/definitions/rerun/blueprint/views/text_log.fbs

@@ -0,0 +1,9 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A text log view.
+table TextLogView (
+    "attr.rerun.view_identifier": "TextLog"
+) {
+}

crates/re_types/definitions/rerun/blueprint/views/time_series.fbs

@@ -0,0 +1,9 @@
+include "rerun/attributes.fbs";
+
+namespace rerun.blueprint.views;
+
+/// A time series view.
+table TimeSeriesView (
+    "attr.rerun.view_identifier": "TimeSeries"
+) {
+}

crates/re_types/src/lib.rs

@@ -3,8 +3,8 @@
 //! This crate contains both the IDL definitions for Rerun types (flatbuffers) as well as the code
 //! generated from those using `re_types_builder`.
 //!
-//! All builtin archetypes, components and datatypes can be found in their respective top-level
-//! modules.
+//! All builtin archetypes, components, datatypes and space view definitions can be found in their
+//! respective top-level modules.
 //!
 //! ## Contributing
 //!

crates/re_types_builder/src/codegen/cpp/mod.rs

@@ -136,6 +136,10 @@ impl crate::CodeGenerator for CppCodeGenerator {
 
         ObjectKind::ALL
             .par_iter()
+            .filter(|&&object_kind| {
+                // TODO(#5521): Implement view codegen for Rust.
+                object_kind != ObjectKind::View
+            })
             .flat_map(|object_kind| {
                 scopes
                     .par_iter()
@@ -405,6 +409,10 @@ impl QuotedObject {
                 ObjectKind::Archetype => {
                     Ok(Self::from_archetype(obj, hpp_includes, hpp_type_extensions))
                 }
+                ObjectKind::View => {
+                    // TODO(#5521): Implement view codegen for Rust.
+                    unimplemented!();
+                }
             },
             ObjectClass::Enum => Ok(Self::from_enum(objects, obj, hpp_includes)),
             ObjectClass::Union => Ok(Self::from_union(

crates/re_types_builder/src/codegen/docs/mod.rs

@@ -56,6 +56,10 @@ impl CodeGenerator for DocsCodeGenerator {
                 ObjectKind::Datatype => datatypes.push(object),
                 ObjectKind::Component => components.push(object),
                 ObjectKind::Archetype => archetypes.push(object),
+                ObjectKind::View => {
+                    // TODO(#6082): Implement view docs generation.
+                    continue;
+                }
             }
 
             let page = object_page(reporter, object, object_map);
@@ -211,6 +215,9 @@ fn object_page(reporter: &Reporter, object: &Object, object_map: &ObjectMap) ->
             write_fields(&mut page, object, object_map);
         }
         ObjectKind::Archetype => write_archetype_fields(&mut page, object, object_map),
+        ObjectKind::View => {
+            // TODO(#6082): Implement view docs generation.
+        }
     }
 
     {
@@ -284,6 +291,9 @@ fn object_page(reporter: &Reporter, object: &Object, object_map: &ObjectMap) ->
                 }
             }
         }
+        ObjectKind::View => {
+            // TODO(#6082): Implement view docs generation.
+        }
     }
 
     page

crates/re_types_builder/src/codegen/python/mod.rs

@@ -1,5 +1,7 @@
 //! Implements the Python codegen pass.
 
+mod views;
+
 use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
 
 use anyhow::Context as _;
@@ -19,6 +21,8 @@ use crate::{
     ObjectKind, Objects, Reporter, Type, ATTR_PYTHON_ALIASES, ATTR_PYTHON_ARRAY_ALIASES,
 };
 
+use self::views::code_for_view;
+
 use super::common::ExampleInfo;
 
 /// The standard python init method.
@@ -322,7 +326,7 @@ impl PythonCodeGenerator {
                         ]
                     }
                 }
-                ObjectKind::Archetype => vec![obj.name.clone()],
+                ObjectKind::View | ObjectKind::Archetype => vec![obj.name.clone()],
             };
 
             // NOTE: Isolating the file stem only works because we're handling datatypes, components
@@ -342,14 +346,18 @@ impl PythonCodeGenerator {
             code.push_indented(0, &format!("# {}", autogen_warning!()), 1);
             if let Some(source_path) = obj.relative_filepath() {
                 code.push_indented(0, &format!("# Based on {:?}.", format_path(source_path)), 2);
-                code.push_indented(
-                    0,
-                    &format!(
-                        "# You can extend this class by creating a {:?} class in {:?}.",
-                        ext_class.name, ext_class.file_name
-                    ),
-                    2,
-                );
+
+                if obj.kind != ObjectKind::View {
+                    // View type extension isn't implemented yet (shouldn't be hard though to add if needed).
+                    code.push_indented(
+                        0,
+                        &format!(
+                            "# You can extend this class by creating a {:?} class in {:?}.",
+                            ext_class.name, ext_class.file_name
+                        ),
+                        2,
+                    );
+                }
             }
 
             let manifest = quote_manifest(names);
@@ -436,13 +444,17 @@ impl PythonCodeGenerator {
 
             let obj_code = match obj.class {
                 crate::objects::ObjectClass::Struct => {
-                    code_for_struct(reporter, arrow_registry, &ext_class, objects, obj)
+                    if obj.kind == ObjectKind::View {
+                        code_for_view(reporter, objects, obj)
+                    } else {
+                        code_for_struct(reporter, arrow_registry, &ext_class, objects, obj)
+                    }
                 }
                 crate::objects::ObjectClass::Enum => {
                     code_for_enum(reporter, arrow_registry, &ext_class, objects, obj)
                 }
                 crate::objects::ObjectClass::Union => {
-                    code_for_union(arrow_registry, &ext_class, objects, obj)
+                    code_for_union(reporter, arrow_registry, &ext_class, objects, obj)
                 }
             };
 
@@ -458,7 +470,7 @@ impl PythonCodeGenerator {
             files_to_write.insert(filepath.clone(), code);
         }
 
-        // rerun/[{scope}]/{datatypes|components|archetypes}/__init__.py
+        // rerun/[{scope}]/{datatypes|components|archetypes|space_views}/__init__.py
         write_init_file(&kind_path, &mods, files_to_write);
         write_init_file(&test_kind_path, &test_mods, files_to_write);
         for (scope, mods) in scoped_mods {
@@ -476,6 +488,10 @@ fn write_init_file(
     mods: &BTreeMap<String, Vec<String>>,
     files_to_write: &mut BTreeMap<Utf8PathBuf, String>,
 ) {
+    if mods.is_empty() {
+        return;
+    }
+
     let path = kind_path.join("__init__.py");
     let mut code = String::new();
     let manifest = quote_manifest(mods.iter().flat_map(|(_, names)| names.iter()));
@@ -766,6 +782,9 @@ fn code_for_struct(
                 1,
             );
         }
+        ObjectKind::View => {
+            unreachable!("View processing shouldn't reach struct generation code.");
+        }
     }
 
     code
@@ -915,12 +934,16 @@ return pa.UnionArray.from_buffers(
                 1,
             );
         }
+        ObjectKind::View => {
+            reporter.error(&obj.virtpath, &obj.fqname, "A view cannot be an enum");
+        }
     }
 
     code
 }
 
 fn code_for_union(
+    reporter: &Reporter,
     arrow_registry: &ArrowRegistry,
     ext_class: &ExtensionClass,
     objects: &Objects,
@@ -1062,7 +1085,7 @@ fn code_for_union(
     match kind {
         ObjectKind::Archetype => (),
         ObjectKind::Component => {
-            unreachable!("component may not be a union")
+            reporter.error(&obj.virtpath, &obj.fqname, "An component cannot be an enum");
         }
         ObjectKind::Datatype => {
             code.push_indented(
@@ -1071,6 +1094,9 @@ fn code_for_union(
                 1,
             );
         }
+        ObjectKind::View => {
+            reporter.error(&obj.virtpath, &obj.fqname, "An view cannot be an enum");
+        }
     }
 
     code
@@ -1970,15 +1996,10 @@ fn quote_init_method(
             })
             .collect::<Vec<_>>()
     };
-    let doc_typedesc = match obj.kind {
-        ObjectKind::Datatype => "datatype",
-        ObjectKind::Component => "component",
-        ObjectKind::Archetype => "archetype",
-    };
-
     let mut doc_string_lines = vec![format!(
-        "Create a new instance of the {} {doc_typedesc}.",
-        obj.name
+        "Create a new instance of the {} {}.",
+        obj.name,
+        obj.kind.singular_name().to_lowercase()
     )];
     if !parameter_docs.is_empty() {
         doc_string_lines.push("\n".to_owned());