paleolimbot commented on code in PR #45459: URL: https://github.com/apache/arrow/pull/45459#discussion_r2059536882
########## cpp/src/parquet/geospatial/util_internal.h: ########## @@ -0,0 +1,216 @@ +// 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. + +#pragma once + +#include <algorithm> +#include <array> +#include <cmath> +#include <limits> +#include <string> +#include <unordered_set> + +#include "arrow/util/logging_internal.h" +#include "parquet/platform.h" + +namespace parquet::geospatial { + +/// \brief Infinity, used to define bounds of empty bounding boxes +constexpr double kInf = std::numeric_limits<double>::infinity(); + +/// \brief Valid combinations of dimensions allowed by ISO well-known binary +/// +/// These values correspond to the 0, 1000, 2000, 3000 component of the WKB integer +/// geometry type (i.e., the value of geometry_type // 1000). +enum class Dimensions { + kXY = 0, + kXYZ = 1, + kXYM = 2, + kXYZM = 3, + kValueMin = 0, + kValueMax = 3 +}; + +/// \brief The supported set of geometry types allowed by ISO well-known binary +/// +/// These values correspond to the 1, 2, ..., 7 component of the WKB integer +/// geometry type (i.e., the value of geometry_type % 1000). +enum class GeometryType { + kPoint = 1, + kLinestring = 2, + kPolygon = 3, + kMultiPoint = 4, + kMultiLinestring = 5, + kMultiPolygon = 6, + kGeometryCollection = 7, + kValueMin = 1, + kValueMax = 7 +}; + +/// \brief A collection of intervals representing the encountered ranges of values +/// in each dimension. +/// +/// The Parquet specification also supports wraparound bounding boxes in the X +/// dimension; however, this structure assumes min < max always as it is used for +/// the purposes of accumulating this type of bounds. +/// +/// This class will ignore any NaN values it visits via UpdateXY[Z[M]](). This is +/// consistent with GEOS and ensures that ranges are accumulated in the same way that +/// other statistics in Parquet are accumulated (e.g., statistics of a double column will +/// return a min/max of all non-NaN values). In WKB specifically, POINT EMPTY is +/// represented by convention as all ordinate values filled with NaN, so this behaviour +/// allows for no special-casing of POINT EMPTY in the WKB reader. +/// +/// This class will propagate any NaN values (per dimension) that were explicitly +/// specified via setting mins/maxes directly or by merging another BoundingBox that +/// contained NaN values. This definition ensures that NaN bounds obtained via +/// EncodedGeoStatistics (which may have been written by some other writer that generated +/// NaNs, either on purpose or by accident) are not silently overwritten. +struct PARQUET_EXPORT BoundingBox { + using XY = std::array<double, 2>; + using XYZ = std::array<double, 3>; + using XYM = std::array<double, 3>; + using XYZM = std::array<double, 4>; + + BoundingBox(const XYZM& mins, const XYZM& maxes) : min(mins), max(maxes) {} + BoundingBox() : min{kInf, kInf, kInf, kInf}, max{-kInf, -kInf, -kInf, -kInf} {} + + BoundingBox(const BoundingBox& other) = default; + BoundingBox& operator=(const BoundingBox&) = default; + + /// \brief Update the X and Y bounds to ensure these bounds contain coord + void UpdateXY(::arrow::util::span<const double> coord) { + DCHECK_EQ(coord.size(), 2); + UpdateInternal(coord); + } + + /// \brief Update the X, Y, and Z bounds to ensure these bounds contain coord + void UpdateXYZ(::arrow::util::span<const double> coord) { + DCHECK_EQ(coord.size(), 3); + UpdateInternal(coord); + } + + /// \brief Update the X, Y, and M bounds to ensure these bounds contain coord + void UpdateXYM(::arrow::util::span<const double> coord) { + DCHECK_EQ(coord.size(), 3); + min[0] = std::min(min[0], coord[0]); + min[1] = std::min(min[1], coord[1]); + min[3] = std::min(min[3], coord[2]); + max[0] = std::max(max[0], coord[0]); + max[1] = std::max(max[1], coord[1]); + max[3] = std::max(max[3], coord[2]); + } + + /// \brief Update the X, Y, Z, and M bounds to ensure these bounds contain coord + void UpdateXYZM(::arrow::util::span<const double> coord) { + DCHECK_EQ(coord.size(), 4); + UpdateInternal(coord); + } + + /// \brief Reset these bounds to an empty state such that they contain no coordinates + void Reset() { + for (int i = 0; i < 4; i++) { + min[i] = kInf; + max[i] = -kInf; + } + } + + /// \brief Update these bounds such they also contain other + void Merge(const BoundingBox& other) { + for (int i = 0; i < 4; i++) { + if (std::isnan(min[i]) || std::isnan(max[i]) || std::isnan(other.min[i]) || + std::isnan(other.max[i])) { + min[i] = std::numeric_limits<double>::quiet_NaN(); + max[i] = std::numeric_limits<double>::quiet_NaN(); + } else { + min[i] = std::min(min[i], other.min[i]); + max[i] = std::max(max[i], other.max[i]); + } + } + } + + std::string ToString() const; + + XYZM min; + XYZM max; + + private: + // This works for XY, XYZ, and XYZM + template <typename Coord> + void UpdateInternal(Coord coord) { + for (size_t i = 0; i < coord.size(); i++) { + min[i] = std::min(min[i], coord[i]); + max[i] = std::max(max[i], coord[i]); + } + } +}; + +inline bool operator==(const BoundingBox& lhs, const BoundingBox& rhs) { + return lhs.min == rhs.min && lhs.max == rhs.max; +} + +inline bool operator!=(const BoundingBox& lhs, const BoundingBox& rhs) { + return !(lhs == rhs); +} + +class WKBBuffer; + +/// \brief Accumulate a BoundingBox and geometry types based on zero or more well-known +/// binary blobs +/// +/// Note that this class is NOT appropriate for bounding a GEOGRAPHY, +/// whose bounds are not a function purely of the vertices. Geography bounding +/// is not yet implemented. +class PARQUET_EXPORT WKBGeometryBounder { + public: + /// \brief Accumulate the bounds of a serialized well-known binary geometry + /// + /// Throws ParquetException for any parse errors encountered. Bounds for + /// any encountered coordinates are accumulated and the geometry type of + /// the geometry is added to the internal geometry type list. + void MergeGeometry(std::string_view bytes_wkb); Review Comment: Done! (And used in the tests to make them more concise!) -- 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: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
