Merge pull request #330 from geo-engine/point-clustering

Point clustering

Author: michaelmattig

datatypes/src/collections/feature_collection_builder.rs

@@ -227,6 +227,42 @@ where
         Ok(())
     }
 
+    /// Append a null to `column` if possible
+    pub fn push_null(&mut self, column: &str) -> Result<()> {
+        // also checks that column exists
+        let data_builder = if let Some(builder) = self.builders.get_mut(column) {
+            builder
+        } else {
+            return Err(FeatureCollectionError::ColumnDoesNotExist {
+                name: column.to_string(),
+            }
+            .into());
+        };
+
+        match self.types.get(column).expect("checked before") {
+            FeatureDataType::Category => {
+                let category_builder: &mut UInt8Builder = downcast_mut_array(data_builder.as_mut());
+                category_builder.append_null()?;
+            }
+            FeatureDataType::Int => {
+                let category_builder: &mut Int64Builder = downcast_mut_array(data_builder.as_mut());
+                category_builder.append_null()?;
+            }
+            FeatureDataType::Float => {
+                let category_builder: &mut Float64Builder =
+                    downcast_mut_array(data_builder.as_mut());
+                category_builder.append_null()?;
+            }
+            FeatureDataType::Text => {
+                let category_builder: &mut StringBuilder =
+                    downcast_mut_array(data_builder.as_mut());
+                category_builder.append_null()?;
+            }
+        }
+
+        Ok(())
+    }
+
     /// Indicate a finished row
     pub fn finish_row(&mut self) {
         self.rows += 1;

datatypes/src/operations/mod.rs

@@ -1,2 +1,5 @@
 pub mod image;
 pub mod reproject;
+mod spatial_relation;
+
+pub use spatial_relation::Contains;

datatypes/src/operations/spatial_relation.rs

@@ -0,0 +1,10 @@
+/// This method returns `true` iff `Self` contains the input `T`.
+/// It is valid if the `T` touches the `Self`'s borders.
+pub trait Contains<T> {
+    fn contains(&self, other: &T) -> bool;
+}
+
+/// This method returns `true` iff does this `Self` intersect with the input `T`
+pub trait Intersects<T> {
+    fn contains(&self, other: &T) -> bool;
+}

datatypes/src/primitives/bounding_box.rs

@@ -124,6 +124,35 @@ impl BoundingBox2D {
         BoundingBox2D::new_unchecked(lower_left_coordinate, upper_right_coordinate)
     }
 
+    /// Creates a new bounding box with `upper_left` and `lower_right` coordinates
+    /// This is usually used with raster data and matches with the gdal geotransform
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use geoengine_datatypes::primitives::{Coordinate2D, BoundingBox2D};
+    ///
+    /// let ul = Coordinate2D::new(1.0, 2.0);
+    /// let lr = Coordinate2D::new(2.0, 1.0);
+    /// let bbox = BoundingBox2D::new_upper_left_lower_right(ul, lr).unwrap();
+    /// ```
+    ///
+    /// # Errors
+    ///
+    /// This constructor fails if the order of coordinates is not correct
+    ///
+    pub fn new_from_center(
+        center: Coordinate2D,
+        half_width: f64,
+        half_height: f64,
+    ) -> Result<Self> {
+        // TODO: fail if half_width or half_height is negative
+
+        let lower_left_coordinate = (center.x - half_width, center.y - half_height).into();
+        let upper_right_coordinate = (center.x + half_width, center.y + half_height).into();
+        BoundingBox2D::new(lower_left_coordinate, upper_right_coordinate)
+    }
+
     /// Checks if a coordinate is located inside the bounding box
     ///
     /// # Examples
@@ -340,6 +369,49 @@ impl BoundingBox2D {
             f
         })
     }
+
+    /// This method generates four new `BoundingBox2D`s by splitting the current one in four quadrants.
+    pub fn split_into_quarters(&self) -> (Self, Self, Self, Self) {
+        let half_width = self.size_x() / 2.;
+        let half_height = self.size_x() / 2.;
+
+        let upper_left = Self::new_unchecked(
+            Coordinate2D::new(
+                self.lower_left_coordinate.x,
+                self.lower_left_coordinate.y + half_height,
+            ),
+            Coordinate2D::new(
+                self.lower_left_coordinate.x + half_width,
+                self.upper_right_coordinate.y,
+            ),
+        );
+        let upper_right = Self::new_unchecked(
+            Coordinate2D::new(
+                self.lower_left_coordinate.x + half_width,
+                self.lower_left_coordinate.y + half_height,
+            ),
+            self.upper_right_coordinate,
+        );
+        let lower_left = Self::new_unchecked(
+            self.lower_left_coordinate,
+            Coordinate2D::new(
+                self.lower_left_coordinate.x + half_width,
+                self.lower_left_coordinate.y + half_height,
+            ),
+        );
+        let lower_right = Self::new_unchecked(
+            Coordinate2D::new(
+                self.lower_left_coordinate.x + half_width,
+                self.lower_left_coordinate.y,
+            ),
+            Coordinate2D::new(
+                self.upper_right_coordinate.x,
+                self.lower_left_coordinate.y + half_height,
+            ),
+        );
+
+        (lower_left, lower_right, upper_left, upper_right)
+    }
 }
 
 impl AxisAlignedRectangle for BoundingBox2D {
@@ -481,6 +553,7 @@ impl TryFrom<BoundingBox2D> for gdal::vector::Geometry {
 mod tests {
 
     use crate::primitives::{AxisAlignedRectangle, BoundingBox2D, Coordinate2D, SpatialBounded};
+
     #[test]
     #[allow(clippy::float_cmp)]
     fn bounding_box_new() {
@@ -985,4 +1058,36 @@ mod tests {
         let bbox = BoundingBox2D::from_coord_ref_iter(coordinates.iter()).unwrap();
         assert_eq!(bbox, expected);
     }
+
+    #[test]
+    fn test_split_into_quarters() {
+        let bbox = BoundingBox2D::new((-50., -50.).into(), (50., 50.).into()).unwrap();
+
+        let (lower_left, lower_right, upper_left, upper_right) = bbox.split_into_quarters();
+
+        assert_eq!(
+            upper_left,
+            BoundingBox2D::new((-50., 0.).into(), (0., 50.).into()).unwrap()
+        );
+        assert_eq!(
+            upper_right,
+            BoundingBox2D::new((0., 0.).into(), (50., 50.).into()).unwrap()
+        );
+        assert_eq!(
+            lower_left,
+            BoundingBox2D::new((-50., -50.).into(), (0., 0.).into()).unwrap()
+        );
+        assert_eq!(
+            lower_right,
+            BoundingBox2D::new((0., -50.).into(), (50., 0.).into()).unwrap()
+        );
+    }
+
+    #[test]
+    fn test_new_from_center() {
+        assert_eq!(
+            BoundingBox2D::new_from_center((0., 0.).into(), 50., 50.).unwrap(),
+            BoundingBox2D::new((-50., -50.).into(), (50., 50.).into()).unwrap(),
+        );
+    }
 }