paleolimbot commented on code in PR #295: URL: https://github.com/apache/sedona-db/pull/295#discussion_r2518292353
########## c/sedona-geos/src/st_simplify.rs: ########## @@ -0,0 +1,604 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +use std::sync::Arc; + +use arrow_array::builder::BinaryBuilder; +use arrow_schema::DataType; +use datafusion_common::{cast::as_float64_array, DataFusionError, Result}; +use datafusion_expr::ColumnarValue; +use geos::{Geom, Geometry, GeometryTypes}; +use sedona_expr::scalar_udf::{ScalarKernelRef, SedonaScalarKernel}; +use sedona_geometry::wkb_factory::WKB_MIN_PROBABLE_BYTES; +use sedona_schema::{ + datatypes::{SedonaType, WKB_GEOMETRY}, + matchers::ArgMatcher, +}; + +use crate::executor::GeosExecutor; + +pub fn st_simplify_impl() -> ScalarKernelRef { + Arc::new(STSimplify {}) +} + +#[derive(Debug)] +struct STSimplify {} + +impl SedonaScalarKernel for STSimplify { + fn return_type(&self, args: &[SedonaType]) -> Result<Option<SedonaType>> { + let matcher = ArgMatcher::new( + vec![ArgMatcher::is_geometry(), ArgMatcher::is_numeric()], + WKB_GEOMETRY, + ); + + matcher.match_args(args) + } + + fn invoke_batch( + &self, + arg_types: &[SedonaType], + args: &[ColumnarValue], + ) -> Result<ColumnarValue> { + let executor = GeosExecutor::new(arg_types, args); + + let tolerance_value = args[1] + .cast_to(&DataType::Float64, None)? + .to_array(executor.num_iterations())?; + let tolerance_array = as_float64_array(&tolerance_value)?; + let mut tolerance_iter = tolerance_array.iter(); + + let mut builder = BinaryBuilder::with_capacity( + executor.num_iterations(), + WKB_MIN_PROBABLE_BYTES * executor.num_iterations(), + ); + + executor.execute_wkb_void(|wkb| { + match (wkb, tolerance_iter.next().unwrap()) { + (Some(wkb), Some(tolerance)) => { + invoke_scalar(&wkb, tolerance, &mut builder)?; + builder.append_value([]); + } + _ => builder.append_null(), + } + Ok(()) + })?; + + executor.finish(Arc::new(builder.finish())) + } +} + +fn invoke_scalar( + geos_geom: &geos::Geometry, + tolerance: f64, + writer: &mut impl std::io::Write, +) -> Result<()> { + let initial_type = geos_geom.geometry_type(); + let geometry = geos_geom + .simplify(tolerance) + .map_err(|e| DataFusionError::Execution(format!("Failed to simplify geometry: {e}")))?; + + let geometry = match (initial_type, geometry.geometry_type()) { + (GeometryTypes::MultiPolygon, GeometryTypes::Polygon) => { + Geometry::create_multipolygon(vec![geometry]).map_err(|e| { + DataFusionError::Execution(format!("Failed to revert geometry promotion: {e}")) + })? + } + (GeometryTypes::MultiLineString, GeometryTypes::LineString) => { + Geometry::create_multiline_string(vec![geometry]).map_err(|e| { + DataFusionError::Execution(format!("Failed to revert geometry promotion: {e}")) + })? + } + _ => geometry, + }; + + let wkb = geometry + .to_wkb() + .map_err(|e| DataFusionError::Execution(format!("Failed to convert to wkb: {e}")))?; + + writer.write_all(wkb.as_ref())?; + Ok(()) +} + +#[cfg(test)] +mod tests { + use super::*; + use arrow_array::Float64Array; + use datafusion_common::ScalarValue; + use rstest::rstest; + use sedona_expr::scalar_udf::SedonaScalarUDF; + use sedona_schema::datatypes::{WKB_GEOMETRY, WKB_VIEW_GEOMETRY}; + use sedona_testing::{ + compare::assert_array_equal, create::create_array, testers::ScalarUdfTester, + }; + + #[rstest] + fn udf(#[values(WKB_GEOMETRY, WKB_VIEW_GEOMETRY)] sedona_type: SedonaType) { Review Comment: It's useful for us to have the Rust tests because we'd like to implement a faster version at some point, and when we have Rust code we'll need the Rust tests to cover the behaviour. (But yes, the minimum requirement for wrapping external library behaviour is a "is it plugged in" check at the Rust level). -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
