Merge pull request #417 from hannobraun/get_handle

Add `Shape::get_handle`, `Shape::get_handle_or_insert`

fj-kernel/src/shape/api.rs

@@ -6,7 +6,7 @@ use super::{
     stores::{
         Curves, Cycles, Edges, Faces, Points, Stores, Surfaces, Vertices,
     },
-    Geometry, Object, Topology, ValidationResult,
+    Geometry, Handle, Object, Topology, ValidationResult,
 };
 
 /// The boundary representation of a shape
@@ -68,6 +68,45 @@ impl Shape {
         Ok(handle)
     }
 
+    /// Access the handle of an object
+    ///
+    /// Returns the handle that refers to the given object, if it is part of the
+    /// shape. Returns `None`, if it isn't.
+    ///
+    /// # Implementation note
+    ///
+    /// If `object` is present multiple times, the handle of the first that is
+    /// found is returned. This is weird. It would be better, if objects were
+    /// unique, but currently they are stored in `Vec`s.
+    ///
+    /// This probably isn't worth thinking too much about right now. At some
+    /// point, we need smarter and probably more performant object storage
+    /// anyway.
+    pub fn get_handle<T>(&self, object: &T) -> Option<Handle<T>>
+    where
+        T: Object,
+    {
+        self.stores
+            .get::<T>()
+            .iter()
+            .find(|obj| &obj.get() == object)
+    }
+
+    /// Get handle of an identical object, if it exists, or add the object
+    ///
+    /// In any case, returns a handle that refers to an object that is identical
+    /// to the provided object.
+    pub fn get_handle_or_insert<T>(&mut self, object: T) -> ValidationResult<T>
+    where
+        T: Object,
+    {
+        if let Some(handle) = self.get_handle(&object) {
+            return Ok(handle);
+        }
+
+        self.insert(object)
+    }
+
     /// Access the shape's geometry
     pub fn geometry(&mut self) -> Geometry {
         Geometry {
@@ -93,3 +132,70 @@ impl Default for Shape {
         Self::new()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use fj_math::Point;
+
+    use crate::{
+        geometry::{Curve, Surface},
+        shape::Shape,
+        topology::{Cycle, Edge, Face, Vertex},
+    };
+
+    #[test]
+
+    fn get_handle() -> anyhow::Result<()> {
+        let mut shape = Shape::new();
+
+        let point = Point::from([1., 0., 0.]);
+        let curve = Curve::x_axis();
+        let surface = Surface::x_y_plane();
+
+        assert!(shape.get_handle(&point).is_none());
+        assert!(shape.get_handle(&curve).is_none());
+        assert!(shape.get_handle(&surface).is_none());
+
+        let point = shape.insert(point)?;
+        let curve = shape.insert(curve)?;
+        let surface = shape.insert(surface)?;
+
+        assert!(shape.get_handle(&point.get()).as_ref() == Some(&point));
+        assert!(shape.get_handle(&curve.get()).as_ref() == Some(&curve));
+        assert!(shape.get_handle(&surface.get()).as_ref() == Some(&surface));
+
+        let vertex = Vertex { point };
+        let edge = Edge {
+            curve,
+            vertices: None,
+        };
+
+        assert!(shape.get_handle(&vertex).is_none());
+        assert!(shape.get_handle(&edge).is_none());
+
+        let vertex = shape.insert(vertex)?;
+        let edge = shape.insert(edge)?;
+
+        assert!(shape.get_handle(&vertex.get()).as_ref() == Some(&vertex));
+        assert!(shape.get_handle(&edge.get()).as_ref() == Some(&edge));
+
+        let cycle = Cycle { edges: vec![edge] };
+        assert!(shape.get_handle(&cycle).is_none());
+
+        let cycle = shape.insert(cycle)?;
+        assert!(shape.get_handle(&cycle.get()).as_ref() == Some(&cycle));
+
+        let face = Face::Face {
+            surface,
+            exteriors: Vec::new(),
+            interiors: Vec::new(),
+            color: [0, 0, 0, 0],
+        };
+        assert!(shape.get_handle(&face).is_none());
+
+        let face = shape.insert(face)?;
+        assert!(shape.get_handle(&face.get()).as_ref() == Some(&face));
+
+        Ok(())
+    }
+}

fj-kernel/src/shape/object.rs

@@ -8,7 +8,10 @@ use crate::{
 use super::validate::Validate;
 
 /// Marker trait for geometric and topological objects
-pub trait Object: 'static + Validate + private::Sealed {}
+pub trait Object:
+    'static + Clone + PartialEq + Validate + private::Sealed
+{
+}
 
 impl private::Sealed for Point<3> {}
 impl private::Sealed for Curve {}

fj-kernel/src/shape/stores.rs

@@ -28,7 +28,7 @@ pub struct Stores {
 }
 
 impl Stores {
-    pub fn get<T>(&mut self) -> Store<T>
+    pub fn get<T>(&self) -> Store<T>
     where
         T: Object,
     {