Add C++ point3d_ui_radius demo & C++ radius extensions

crates/re_types/definitions/rerun/archetypes/points3d.fbs

@@ -11,6 +11,7 @@ namespace rerun.archetypes;
 ///
 /// \example archetypes/point3d_simple !api title="Simple 3D points" image="https://static.rerun.io/point3d_simple/32fb3e9b65bea8bd7ffff95ad839f2f8a157a933/1200w.png"
 /// \example archetypes/point3d_random title="Randomly distributed 3D points with varying color and radius" image="https://static.rerun.io/point3d_random/7e94e1806d2c381943748abbb3bedb68d564de24/1200w.png"
+/// \example archetypes/point3d_ui_radius title="Log points with radii given in ui points" image="https://static.rerun.io/point3d_ui_radius/e051a65b4317438bcaea8d0eee016ac9460b5336/1200w.png"
 table Points3D (
   "attr.rust.derive": "PartialEq",
   "attr.docs.category": "Spatial 3D",

docs/snippets/all/archetypes/point3d_ui_radius.cpp

@@ -1,12 +1,31 @@
-// Log some very simple points.
+// Log some points with ui points & scene unit radii.
 
 #include <rerun.hpp>
 
 int main() {
     const auto rec = rerun::RecordingStream("rerun_example_points3d_ui_radius");
     rec.spawn().exit_on_failure();
 
-    rec.log("points", rerun::Points3D({{0.0f, 0.0f, 0.0f}, {1.0f, 1.0f, 1.0f}}));
-}
+    // Two blue points with scene unit radii of 0.1 and 0.3.
+    rec.log(
+        "scene_unit_points",
+        rerun::Points3D({{0.0f, 1.0f, 0.0f}, {1.0f, 1.0f, 1.0f}})
+            // By default, radii are interpreted as world-space units.
+            .with_radii({0.1f, 0.3f})
+            .with_colors(rerun::Color(0, 0, 255))
+    );
 
-// TODO: unfinished
+    // Two red points with ui point radii of 40 and 60.
+    // Ui points are independent of zooming in Views, but are sensitive to the application ui scaling.
+    // For 100% ui scaling, ui points are equal to pixels.
+    rec.log(
+        "ui_points_points",
+        rerun::Points3D({{0.0f, 0.0f, 0.0}, {1.0f, 0.0f, 1.0f}})
+            // rerun::Radius::ui_points produces radii that the viewer interprets as given in ui points.
+            .with_radii({
+                rerun::Radius::ui_points(40.0f),
+                rerun::Radius::ui_points(60.0f),
+            })
+            .with_colors(rerun::Color(255, 0, 0))
+    );
+}

docs/snippets/all/archetypes/point3d_ui_radius.py

@@ -22,7 +22,7 @@
     "ui_points_points",
     rr.Points3D(
         [[0, 0, 0], [1, 0, 1]],
-        # rr.Radius.ui_points produces radii that the viewer interprets as given in ui units.
+        # rr.Radius.ui_points produces radii that the viewer interprets as given in ui points.
         radii=rr.Radius.ui_points([40.0, 60.0]),
         colors=[255, 0, 0],
     ),

docs/snippets/all/archetypes/point3d_ui_radius.rs

@@ -18,7 +18,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     rec.log(
         "ui_points_points",
         &rerun::Points3D::new([(0.0, 0.0, 0.0), (1.0, 0.0, 1.0)])
-            // rr.Radius.ui_points produces radii that the viewer interprets as given in ui units.
+            // rerun::Radius::new_ui_points produces a radius that the viewer interprets as given in ui points.
             .with_radii([
                 rerun::Radius::new_ui_points(40.0),
                 rerun::Radius::new_ui_points(60.0),

rerun_cpp/src/rerun/components/radius_ext.cpp

@@ -0,0 +1,30 @@
+//#define EDIT_EXTENSION
+#if EDIT_EXTENSION
+
+#include "radius.hpp"
+
+// Uncomment for better auto-complete while editing the extension.
+
+namespace rerun {
+    namespace components {
+        // <CODEGEN_COPY_TO_HEADER>
+
+        /// Creates a new radius in scene units.
+        ///
+        /// Values passed must be finite positive.
+        static Radius scene_units(float radius_in_scene_units) {
+            return Radius(radius_in_scene_units);
+        }
+
+        /// Creates a new radius in ui points.
+        ///
+        /// Values passed must be finite positive.
+        static Radius ui_points(float radius_in_ui_points) {
+            return Radius(-radius_in_ui_points);
+        }
+
+        // </CODEGEN_COPY_TO_HEADER>
+    } // namespace components
+} // namespace rerun
+
+#endif