wip: proj transform

Author: michaelkirk

geozero/Cargo.toml

@@ -24,6 +24,7 @@ with-postgis-sqlx = ["with-wkb", "sqlx/postgres"]
 with-postgis-postgres = ["with-wkb", "postgres-types", "bytes"]
 with-mvt = ["prost"]
 with-tessellator = ["lyon"]
+with-proj = ["proj", "delegate"]
 
 [dependencies]
 thiserror = "1.0"
@@ -40,6 +41,8 @@ postgres-types = { version = "0.2", optional = true }
 bytes = { version = "1.1", optional = true }
 prost = { version = "0.9.0", optional = true }
 wkt = { version = "0.10.0", optional = true }
+proj = { version = "0.25.2", optional = true }
+delegate = { version = "0.6.2", optional = true }
 
 [dev-dependencies]
 seek_bufread = "1.2"

geozero/src/lib.rs

@@ -33,6 +33,7 @@ pub mod error;
 mod feature_processor;
 mod geometry_processor;
 mod multiplex;
+mod proj;
 mod property_processor;
 
 pub use api::*;
@@ -72,6 +73,9 @@ pub mod svg;
 #[cfg(feature = "with-svg")]
 pub use crate::svg::conversion::*;
 
+#[cfg(feature = "with-proj")]
+pub use crate::proj::ToProjected;
+
 #[cfg(feature = "with-tesselator")]
 pub mod tessellator;
 

geozero/src/proj.rs

@@ -0,0 +1,139 @@
+use crate::error::Result;
+use crate::{
+    ColumnValue, CoordDimensions, FeatureProcessor, GeomProcessor, GeozeroDatasource,
+    PropertyProcessor,
+};
+
+use delegate::delegate;
+use proj::Proj;
+
+use std::rc::Rc;
+
+/// ```
+/// use proj::Proj;
+/// use geozero::{ToProjected, ProcessToJson, wkt::WktStr};
+///
+/// // Convert from [NAD 83 US Survey Feet](https://epsg.io/2230) to [NAD 83 Meters](https://epsg.io/26946) Using EPSG Codes
+/// let from = "EPSG:2230";
+/// let to = "EPSG:26946";
+/// let proj = Proj::new_known_crs(from, to, None).unwrap();
+///
+/// let wkt = WktStr("POINT (4760096.421921 3744293.729449)");
+/// let expected = r#"{"type": "Point", "coordinates": [1450880.2910605022,1141263.0111604782]}"#;
+/// assert_eq!(expected, &wkt.to_projected(proj).to_json().unwrap());
+/// ```
+pub trait ToProjected: GeozeroDatasource + Sized {
+    fn to_projected(self, proj: Proj) -> ProjectorReader<Self>;
+}
+
+impl<Input: GeozeroDatasource> ToProjected for Input {
+    fn to_projected(self, proj: Proj) -> ProjectorReader<Input> {
+        ProjectorReader {
+            proj: Rc::new(proj),
+            input: self,
+        }
+    }
+}
+
+pub struct ProjectorReader<Input: GeozeroDatasource> {
+    proj: Rc<Proj>,
+    input: Input,
+}
+
+struct ProjWriter<'a> {
+    proj: Rc<Proj>,
+    output: &'a mut dyn FeatureProcessor,
+}
+
+impl<Input: GeozeroDatasource> GeozeroDatasource for ProjectorReader<Input> {
+    fn process<P: FeatureProcessor>(&mut self, processor: &mut P) -> Result<()> {
+        let mut wrapped = ProjWriter {
+            proj: self.proj.clone(),
+            output: processor,
+        };
+        self.input.process(&mut wrapped)
+    }
+}
+
+impl FeatureProcessor for ProjWriter<'_> {
+    delegate! {
+         to self.output {
+             fn dataset_begin(&mut self, name: Option<&str>) -> Result<()>;
+             fn dataset_end(&mut self) -> Result<()>;
+             fn feature_begin(&mut self, idx: u64) -> Result<()>;
+             fn feature_end(&mut self, idx: u64) -> Result<()>;
+             fn properties_begin(&mut self) -> Result<()>;
+             fn properties_end(&mut self) -> Result<()>;
+             fn geometry_begin(&mut self) -> Result<()>;
+             fn geometry_end(&mut self) -> Result<()>;
+        }
+    }
+}
+
+impl PropertyProcessor for ProjWriter<'_> {
+    delegate! {
+        to self.output {
+            fn property(&mut self, idx: usize, name: &str, value: &ColumnValue) -> Result<bool>;
+        }
+    }
+}
+
+impl GeomProcessor for ProjWriter<'_> {
+    fn coordinate(
+        &mut self,
+        x: f64,
+        y: f64,
+        z: Option<f64>,
+        m: Option<f64>,
+        t: Option<f64>,
+        tm: Option<u64>,
+        idx: usize,
+    ) -> Result<()> {
+        let (x, y) = self.proj.convert((x, y)).unwrap();
+        self.output.coordinate(x, y, z, m, t, tm, idx)
+    }
+
+    fn xy(&mut self, x: f64, y: f64, idx: usize) -> Result<()> {
+        let (x, y) = self.proj.convert((x, y)).unwrap();
+        self.output.xy(x, y, idx)
+    }
+
+    delegate! {
+        to self.output {
+            fn dimensions(&self) -> CoordDimensions;
+            fn multi_dim(&self) -> bool;
+            fn srid(&mut self, srid: Option<i32>) -> Result<()>;
+            fn empty_point(&mut self, idx: usize) -> Result<()>;
+            fn point_begin(&mut self, idx: usize) -> Result<()>;
+            fn point_end(&mut self, idx: usize) -> Result<()>;
+            fn multipoint_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn multipoint_end(&mut self, idx: usize) -> Result<()>;
+            fn linestring_begin(&mut self, tagged: bool, size: usize, idx: usize) -> Result<()>;
+            fn linestring_end(&mut self, tagged: bool, idx: usize) -> Result<()>;
+            fn multilinestring_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn multilinestring_end(&mut self, idx: usize) -> Result<()>;
+            fn polygon_begin(&mut self, tagged: bool, size: usize, idx: usize) -> Result<()>;
+            fn polygon_end(&mut self, tagged: bool, idx: usize) -> Result<()>;
+            fn multipolygon_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn multipolygon_end(&mut self, idx: usize) -> Result<()>;
+            fn geometrycollection_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn geometrycollection_end(&mut self, idx: usize) -> Result<()>;
+            fn circularstring_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn circularstring_end(&mut self, idx: usize) -> Result<()>;
+            fn compoundcurve_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn compoundcurve_end(&mut self, idx: usize) -> Result<()>;
+            fn curvepolygon_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn curvepolygon_end(&mut self, idx: usize) -> Result<()>;
+            fn multicurve_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn multicurve_end(&mut self, idx: usize) -> Result<()>;
+            fn multisurface_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn multisurface_end(&mut self, idx: usize) -> Result<()>;
+            fn triangle_begin(&mut self, tagged: bool, size: usize, idx: usize) -> Result<()>;
+            fn triangle_end(&mut self, tagged: bool, idx: usize) -> Result<()>;
+            fn polyhedralsurface_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn polyhedralsurface_end(&mut self, idx: usize) -> Result<()>;
+            fn tin_begin(&mut self, size: usize, idx: usize) -> Result<()>;
+            fn tin_end(&mut self, idx: usize) -> Result<()>;
+        }
+    }
+}