Spatial Indexing

.github/workflows/cmake-multi-platform.yml

@@ -41,9 +41,6 @@ jobs:
         run: |
           echo "build-output-dir=${{ github.workspace }}/build" >> \
           "$GITHUB_OUTPUT"
-      - name: Install OpenMP
-        run: sudo apt -y install libomp-18-dev
-        if: matrix.cpp_compiler == 'clang++'
       - name: Configure CMake
         run: >
           cmake -B ${{ steps.strings.outputs.build-output-dir }}  -DCMAKE_CXX_COMPILER=${{ matrix.cpp_compiler }} -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -S ${{ github.workspace }}

CMakeLists.txt

@@ -3,6 +3,11 @@
 
 cmake_minimum_required(VERSION 3.20)
 
+project(
+  LAS++
+  VERSION 0.0.0
+  LANGUAGES CXX)
+
 option(LASPP_DEBUG_ASSERTS "Enable debugging asserts" ON)
 option(LASPP_BUILD_TESTS "Build tests" ON)
 # Default benchmarks to OFF if this is a subproject (to avoid downloading
@@ -18,11 +23,6 @@ option(LASPP_AGGRESSIVE_OPTIMIZATIONS
        "Enable aggressive performance optimizations (-march=native, etc.)" ON)
 
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-
-project(
-  LAS++
-  VERSION 0.0.0
-  LANGUAGES CXX)
 set(COPYRIGHT "Copyright (c) 2024 Trailblaze Software. All rights reserved.")
 
 if(LASPP_BUILD_TESTS OR LASPP_BUILD_BENCHMARK)
@@ -86,81 +86,103 @@ endif()
 
 # ── Performance optimization flags for aggressive Release builds
 # ──────────────────────────
-if(CMAKE_BUILD_TYPE MATCHES "Release" AND LASPP_AGGRESSIVE_OPTIMIZATIONS)
-  if(MSVC)
-    # Apply only to Release configuration using generator expressions
-    add_compile_options("$<$<CONFIG:Release>:/O2>" "$<$<CONFIG:Release>:/Ob2>"
-                        "$<$<CONFIG:Release>:/GL>")
-    add_link_options("$<$<CONFIG:Release>:/LTCG>")
-    if(HAVE_AVX2)
-      add_compile_options("$<$<CONFIG:Release>:/arch:AVX2>")
-      message(STATUS "AVX2 optimizations enabled for Release builds")
-    endif()
-    message(
-      STATUS "Aggressive performance optimizations enabled for Release builds")
-  elseif(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
-    # For single-config generators (Unix Makefiles), CMAKE_BUILD_TYPE check is
-    # sufficient
-    add_compile_options("-O3" "-march=native" "-flto" "-funroll-loops")
-    add_link_options("-flto")
-    if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-      add_compile_options("-fomit-frame-pointer" "-fno-semantic-interposition")
+# Only apply when this is the top-level project to avoid affecting consuming
+# projects
+if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
+  if(CMAKE_BUILD_TYPE MATCHES "Release" AND LASPP_AGGRESSIVE_OPTIMIZATIONS)
+    if(MSVC)
+      # Apply only to Release configuration using generator expressions
+      add_compile_options(
+        "$<$<CONFIG:Release>:/O2>" "$<$<CONFIG:Release>:/Ob2>"
+        "$<$<CONFIG:Release>:/GL>")
+      add_link_options("$<$<CONFIG:Release>:/LTCG>")
+      if(HAVE_AVX2)
+        add_compile_options("$<$<CONFIG:Release>:/arch:AVX2>")
+        message(STATUS "AVX2 optimizations enabled for Release builds")
+      endif()
+      message(
+        STATUS "Aggressive performance optimizations enabled for Release builds"
+      )
+    elseif(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
+      # For single-config generators (Unix Makefiles), CMAKE_BUILD_TYPE check is
+      # sufficient
+      add_compile_options("-O3" "-march=native" "-flto" "-funroll-loops")
+      add_link_options("-flto")
+      if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+        add_compile_options("-fomit-frame-pointer"
+                            "-fno-semantic-interposition")
+      endif()
+      message(
+        STATUS "Aggressive performance optimizations enabled for Release builds"
+      )
     endif()
+  elseif(CMAKE_BUILD_TYPE MATCHES "Release")
     message(
-      STATUS "Aggressive performance optimizations enabled for Release builds")
+      STATUS
+        "Using standard Release optimizations (LASPP_AGGRESSIVE_OPTIMIZATIONS=OFF)"
+    )
   endif()
-elseif(CMAKE_BUILD_TYPE MATCHES "Release")
-  message(
-    STATUS
-      "Using standard Release optimizations (LASPP_AGGRESSIVE_OPTIMIZATIONS=OFF)"
-  )
 endif()
 
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
-if(WIN32)
-  if(${CMAKE_CXX_COMPILER} MATCHES ".*mingw.*")
-    add_compile_options("-fstrict-enums" "-Wall" "-Wextra" "-Wpedantic"
-                        "-Werror")
-  else()
-    add_compile_options(
-      "/W4"
-      "/WX"
-      # C4267/C4244: size_t/type narrowing inside MSVC STL template bodies.
-      "/wd4267" # size_t narrowing in MSVC STL <xutility> template
-                # instantiations
-      "/wd4244") # type narrowing in MSVC STL <xutility> template instantiations
-  endif()
-elseif(UNIX)
-  if(NOT CMAKE_BUILD_TYPE MATCHES "Release")
-    add_compile_options("-Werror")
-  endif()
-  if(CMAKE_BUILD_TYPE MATCHES "Debug")
-    add_compile_options("-fsanitize=address,undefined"
-                        "-fno-sanitize-recover=all")
-    add_link_options("-fsanitize=address,undefined")
-  endif()
-  add_compile_options(
-    "-fstrict-enums"
-    "-Wall"
-    "-Wextra"
-    "-Wpedantic"
-    "-Wdouble-promotion"
-    "-Wshadow"
-    "-Wpointer-arith"
-    "-Wstrict-aliasing"
-    "-Wnull-dereference"
-    "-Wdouble-promotion"
-    "-Wold-style-cast"
-    "-Wconversion"
-    "-Wsign-conversion")
-  if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+
+# Only apply strict compiler flags when this is the top-level project.
+if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
+  if(WIN32)
+    if(${CMAKE_CXX_COMPILER} MATCHES ".*mingw.*")
+      add_compile_options("-fstrict-enums" "-Wall" "-Wextra" "-Wpedantic"
+                          "-Werror")
+    else()
+      add_compile_options(
+        "/W4"
+        "/WX"
+        # C4267/C4244: size_t/type narrowing inside MSVC STL template bodies.
+        "/wd4267" # size_t narrowing in MSVC STL <xutility> template
+                  # instantiations
+        "/wd4244") # type narrowing in MSVC STL <xutility> template
+                   # instantiations
+    endif()
+  elseif(UNIX)
+    if(NOT CMAKE_BUILD_TYPE MATCHES "Release")
+      add_compile_options("-Werror")
+    endif()
+    if(CMAKE_BUILD_TYPE MATCHES "Debug")
+      # Clang's static ASan conflicts with WSL2's address space layout (Windows
+      # kernel mappings can overlap with ASan's shadow memory region), causing
+      # random segfaults during ASan initialization. Use UBSan only for Clang;
+      # GCC's dynamic ASan works fine.
+      if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+        add_compile_options("-fsanitize=undefined" "-fno-sanitize-recover=all")
+        add_link_options("-fsanitize=undefined")
+      else()
+        add_compile_options("-fsanitize=address,undefined"
+                            "-fno-sanitize-recover=all")
+        add_link_options("-fsanitize=address,undefined")
+      endif()
+    endif()
     add_compile_options(
-      "-Wduplicated-branches" "-Wlogical-op" "-Wrestrict" "-Wcast-align=strict"
-      "-Wduplicated-cond" "-Wuseless-cast")
+      "-fstrict-enums"
+      "-Wall"
+      "-Wextra"
+      "-Wpedantic"
+      "-Wdouble-promotion"
+      "-Wshadow"
+      "-Wpointer-arith"
+      "-Wstrict-aliasing"
+      "-Wnull-dereference"
+      "-Wdouble-promotion"
+      "-Wold-style-cast"
+      "-Wconversion"
+      "-Wsign-conversion")
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+      add_compile_options(
+        "-Wduplicated-branches" "-Wlogical-op" "-Wrestrict"
+        "-Wcast-align=strict" "-Wduplicated-cond" "-Wuseless-cast")
+    endif()
+  else()
+    message(FATAL_ERROR "Unsupported platform")
   endif()
-else()
-  message(FATAL_ERROR "Unsupported platform")
 endif()
 
 set(LIBRARY_NAME las++)
@@ -203,6 +225,10 @@ if(LASPP_BUILD_TESTS)
     target_link_libraries(${TEST_NAME} PRIVATE ${LIBRARY_NAME})
     add_test(NAME ${TEST_NAME} COMMAND ${TEST_NAME})
     target_compile_definitions(${TEST_NAME} PRIVATE LASPP_DEBUG_ASSERTS)
+    # MSVC needs /bigobj for large translation units in debug mode
+    if(MSVC)
+      target_compile_options(${TEST_NAME} PRIVATE $<$<CONFIG:Debug>:/bigobj>)
+    endif()
   endforeach()
 
   if(TARGET test_laszip_interop)

apps/CMakeLists.txt

@@ -7,12 +7,31 @@ add_executable(${LAS2LAS++_EXE_NAME} las2las++.cpp)
 
 target_link_libraries(${LAS2LAS++_EXE_NAME} ${LIBRARY_NAME})
 
+# MSVC needs /bigobj for large translation units in debug mode
+if(MSVC)
+  target_compile_options(${LAS2LAS++_EXE_NAME}
+                         PRIVATE $<$<CONFIG:Debug>:/bigobj>)
+endif()
+
 # Utility to create test files for benchmarking
 add_executable(create_test_file create_test_file.cpp)
 target_link_libraries(create_test_file PRIVATE ${LIBRARY_NAME})
 
+set(INSPECT_VLRS_EXE_NAME las++-inspect-vlrs)
+
+add_executable(${INSPECT_VLRS_EXE_NAME} inspect_vlrs.cpp)
+
+target_link_libraries(${INSPECT_VLRS_EXE_NAME} ${LIBRARY_NAME})
+
+set(VALIDATE_SPATIAL_INDEX_EXE_NAME las++-validate-spatial-index)
+
+add_executable(${VALIDATE_SPATIAL_INDEX_EXE_NAME} validate_spatial_index.cpp)
+
+target_link_libraries(${VALIDATE_SPATIAL_INDEX_EXE_NAME} ${LIBRARY_NAME})
+
 install(
-  TARGETS ${LAS2LAS++_EXE_NAME}
+  TARGETS ${LAS2LAS++_EXE_NAME} ${INSPECT_VLRS_EXE_NAME}
+          ${VALIDATE_SPATIAL_INDEX_EXE_NAME}
   DESTINATION bin
   COMPONENT applications)
 

apps/create_test_file.cpp

@@ -73,12 +73,12 @@ int main(int argc, char* argv[]) {
 
   // Format 1 with compression (0x81)
   LASWriter writer(ofs, 0x81);
-  writer.header().transform().m_scale_factors.x() = 0.01;
-  writer.header().transform().m_scale_factors.y() = 0.01;
-  writer.header().transform().m_scale_factors.z() = 0.01;
-  writer.header().transform().m_offsets.x() = 0.0;
-  writer.header().transform().m_offsets.y() = 0.0;
-  writer.header().transform().m_offsets.z() = 0.0;
+  writer.header().transform().scale_factors().x() = 0.01;
+  writer.header().transform().scale_factors().y() = 0.01;
+  writer.header().transform().scale_factors().z() = 0.01;
+  writer.header().transform().offsets().x() = 0.0;
+  writer.header().transform().offsets().y() = 0.0;
+  writer.header().transform().offsets().z() = 0.0;
 
   writer.write_points<LASPointFormat1>(std::span<const LASPointFormat1>(points), 50000);
 

apps/inspect_vlrs.cpp

@@ -0,0 +1,91 @@
+/*
+ * SPDX-FileCopyrightText: (c) 2025-2026 Trailblaze Software, all rights reserved
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <cmath>
+#include <fstream>
+#include <iomanip>
+#include <iostream>
+#include <string>
+
+#include "las_reader.hpp"
+#include "spatial_index.hpp"
+#include "utilities/assert.hpp"
+#include "utilities/printing.hpp"
+#include "vlr.hpp"
+
+using namespace laspp;
+
+int main(int argc, char* argv[]) {
+  if (argc != 2) {
+    std::cerr << "Usage: " << argv[0] << " <laz_file>" << std::endl;
+    return 1;
+  }
+
+  std::string filename = argv[1];
+  std::filesystem::path file_path(filename);
+  LASReader reader(file_path);
+
+  std::cout << "=== VLRs ===" << std::endl;
+  const auto& vlrs = reader.vlr_headers();
+  for (size_t i = 0; i < vlrs.size(); ++i) {
+    const auto& vlr = vlrs[i];
+    std::cout << "VLR " << i << ":" << std::endl;
+    std::cout << indented(vlr, "  ");
+    std::cout << "  Is LAZ VLR: " << (vlr.is_laz_vlr() ? "yes" : "no") << std::endl;
+    std::cout << "  Is LAStools spatial index VLR: "
+              << (vlr.is_lastools_spatial_index_vlr() ? "yes" : "no") << std::endl;
+    std::cout << std::endl;
+  }
+
+  std::cout << "=== EVLRs ===" << std::endl;
+  const auto& evlrs = reader.evlr_headers();
+  for (size_t i = 0; i < evlrs.size(); ++i) {
+    const auto& evlr = evlrs[i];
+    std::cout << "EVLR " << i << ":" << std::endl;
+    std::cout << indented(evlr, "  ");
+    std::cout << "  Is LAZ VLR: " << (evlr.is_laz_vlr() ? "yes" : "no") << std::endl;
+    std::cout << "  Is LAStools spatial index EVLR: "
+              << (evlr.is_lastools_spatial_index_evlr() ? "yes" : "no") << std::endl;
+
+    // If it's a LAStools spatial index, show more details
+    if (evlr.is_lastools_spatial_index_evlr()) {
+      LASPP_ASSERT(reader.has_lastools_spatial_index(),
+                   "Failed to load LAStools spatial index from EVLR.");
+      std::cout << "Spatial index: " << std::endl;
+      const auto& index = reader.lastools_spatial_index();
+      const auto& quadtree = index.quadtree_header();
+
+      std::cout << "  Spatial index header:" << std::endl;
+      std::cout << indented(quadtree, "    ");
+      std::cout << "  Number of cells: " << index.num_cells() << std::endl;
+
+      // Show cell details
+      size_t total_intervals = 0;
+      for (const auto& [cell_index, cell] : index.cells()) {
+        total_intervals += cell.intervals.size();
+      }
+      std::cout << "  Total intervals: " << total_intervals << std::endl;
+      std::cout << "  Average intervals per cell: " << std::fixed << std::setprecision(1)
+                << (index.num_cells() > 0 ? static_cast<double>(total_intervals) /
+                                                static_cast<double>(index.num_cells())
+                                          : 0.0)
+                << std::endl;
+
+      // Show first few cells as examples
+      std::cout << indented(limited_map(index.cells(), 3), "    ") << std::endl;
+    }
+    std::cout << std::endl;
+  }
+
+  if (reader.has_lastools_spatial_index()) {
+    const auto& spatial_index = reader.lastools_spatial_index();
+    std::cout << "Loaded LAStools spatial index with " << spatial_index.num_cells() << " cells."
+              << std::endl;
+    std::cout << "Spatial index details:" << std::endl;
+    std::cout << indented(spatial_index, "  ") << std::endl;
+  }
+
+  return 0;
+}