Make IfcParseExamples buildable outside of the main build tree

It's a very verbose version of consuming IfcOpenShell cmake package, but we'll be able to use it as a start point to build upon.

.github/workflows/ci.yml

@@ -118,6 +118,31 @@ jobs:
             -DCMAKE_CXX_FLAGS_INIT="-fPIC"
           sudo make -j$(nproc) install
 
+      # We need zstd and libxml2 just for cmake config files to test the examples build.
+      # zslibzstd-dev has cmake config only on Ubuntu 24.04+.
+      - name : Build zstd
+        run: |
+          git clone https://github.com/facebook/zstd --depth 1 --branch v1.5.7
+          cd zstd
+          # `build` already exists.
+          mkdir build_ && cd build_
+          cmake ../build/cmake -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+            -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+          sudo cmake --build . --target install -j $(nproc)
+
+      # libxml2-dev doesn't have cmake configs even on Ubuntu 24.04+.
+      - name: Build libxml2
+        run: |
+          git clone https://gitlab.gnome.org/GNOME/libxml2.git --branch v2.13.8 --depth 1
+          cd libxml2
+          mkdir build && cd build
+          cmake .. \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_C_COMPILER_LAUNCHER=ccache \
+            -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+          sudo cmake --build . --target install -j $(nproc)
+
       # Ubuntu has `swig` package, but we build it to match the version we use in the main build.
       # To avoid failing tests when checking stub generation.
       - name: build swig
@@ -178,6 +203,14 @@ jobs:
         run: |
           IfcConvert test/input/acad2010_walls.ifc test/input/acad2010_walls.obj
 
+      - name: Build standalone examples to test cmake package
+        run: |
+          cd src/examples
+          mkdir build && cd build
+          cmake .. -DCMAKE_BUILD_TYPE=Release
+          cmake --build .
+          ./IfcParseExamples "../IfcParseExamples_test.ifc"
+
       - name: Test ifcopenshell-python
         run: |
           cd test

.gitignore

@@ -4,6 +4,7 @@
 /_deps-vs*-x*-installed/
 /_installed-vs*-x*/
 /build/
+/src/examples/build/
 
 # output directories
 /cmake/out/

src/examples/CMakeLists.txt

@@ -17,31 +17,59 @@
 #                                                                              #
 ################################################################################
 
-if(SCHEMA_VERSIONS MATCHES "2x3")
+# Thils file can also be build standalone, outside of the IfcOpenShell build tree,
-    ADD_EXECUTABLE(IfcParseExamples IfcParseExamples.cpp)
+# to demonstrate the usage IfcOpenShell as a cmake package.
-    TARGET_LINK_LIBRARIES(IfcParseExamples IfcParse)
+if(NOT BUILD_EXAMPLES)
-    set_target_properties(IfcParseExamples PROPERTIES FOLDER Examples)
+    set(STANDALONE_PROJECT ON)
-    target_compile_features(IfcParseExamples PUBLIC cxx_std_17)
+endif()
 
-    if(WITH_OPENCASCADE)
+if(STANDALONE_PROJECT)
+    cmake_minimum_required(VERSION 3.21)
+    project(IfcOpenShellExamples)
 
-        ADD_EXECUTABLE(IfcOpenHouse IfcOpenHouse.cpp)
+    set(Boost_USE_STATIC_LIBS ON)
-        TARGET_LINK_LIBRARIES(IfcOpenHouse ${IFCOPENSHELL_LIBRARIES} ${OpenCASCADE_LIBRARIES})
+    set(Boost_USE_STATIC_RUNTIME OFF)
+    set(Boost_USE_MULTITHREADED ON)
+    set(Boost_COMPONENTS system program_options regex thread date_time iostreams)
+    find_package(Boost CONFIG REQUIRED COMPONENTS ${Boost_COMPONENTS})
+    find_package(zstd CONFIG REQUIRED)
+    find_package(RocksDB CONFIG REQUIRED)
+    find_package(LibXml2 CONFIG REQUIRED)
+    find_package(IfcOpenShell CONFIG REQUIRED)
+endif()
+
+if(STANDALONE_PROJECT OR SCHEMA_VERSIONS MATCHES "2x3")
+    add_executable(IfcParseExamples IfcParseExamples.cpp)
+
+    if(STANDALONE_PROJECT)
+        target_include_directories(IfcParseExamples PRIVATE ${Boost_INCLUDE_DIRS})
+        target_link_libraries(IfcParseExamples ${Boost_LIBRARIES})
+        target_link_libraries(IfcParseExamples IfcOpenShell::IfcParse)
+        target_compile_features(IfcParseExamples PRIVATE cxx_std_17)
+        target_compile_definitions(IfcParseExamples PRIVATE "SCHEMA_SEQ=(2x3)" HAS_SCHEMA_2x3 IFOPSH_WITH_ROCKSDB)
+    else()
+        target_link_libraries(IfcParseExamples IfcParse)
+        set_target_properties(IfcParseExamples PROPERTIES FOLDER Examples)
+        target_compile_features(IfcParseExamples PRIVATE cxx_std_17)
+    endif()
+
+    if(NOT STANDALONE_PROJECT AND WITH_OPENCASCADE)
+        add_executable(IfcOpenHouse IfcOpenHouse.cpp)
+        target_link_libraries(IfcOpenHouse ${IFCOPENSHELL_LIBRARIES} ${OpenCASCADE_LIBRARIES})
         set_target_properties(IfcOpenHouse PROPERTIES FOLDER Examples)
 
-        ADD_EXECUTABLE(IfcAdvancedHouse IfcAdvancedHouse.cpp)
+        add_executable(IfcAdvancedHouse IfcAdvancedHouse.cpp)
-        TARGET_LINK_LIBRARIES(IfcAdvancedHouse ${IFCOPENSHELL_LIBRARIES} ${OpenCASCADE_LIBRARIES})
+        target_link_libraries(IfcAdvancedHouse ${IFCOPENSHELL_LIBRARIES} ${OpenCASCADE_LIBRARIES})
         set_target_properties(IfcAdvancedHouse PROPERTIES FOLDER Examples)
-
     endif()
-endif(SCHEMA_VERSIONS MATCHES "2x3")
+endif()
 
-if(SCHEMA_VERSIONS MATCHES "4x3_add2")
+if(NOT STANDALONE_PROJECT AND SCHEMA_VERSIONS MATCHES "4x3_add2")
-    ADD_EXECUTABLE(IfcAlignment IfcAlignment.cpp)
+    add_executable(IfcAlignment IfcAlignment.cpp)
-    TARGET_LINK_LIBRARIES(IfcAlignment ${IFCOPENSHELL_LIBRARIES})
+    target_link_libraries(IfcAlignment ${IFCOPENSHELL_LIBRARIES})
     set_target_properties(IfcAlignment PROPERTIES FOLDER Examples)
 
-    ADD_EXECUTABLE(IfcSimplifiedAlignment IfcSimplifiedAlignment.cpp)
+    add_executable(IfcSimplifiedAlignment IfcSimplifiedAlignment.cpp)
-    TARGET_LINK_LIBRARIES(IfcSimplifiedAlignment ${IFCOPENSHELL_LIBRARIES})
+    target_link_libraries(IfcSimplifiedAlignment ${IFCOPENSHELL_LIBRARIES})
     set_target_properties(IfcSimplifiedAlignment PROPERTIES FOLDER Examples)
 endif()

src/examples/IfcParseExamples_test.ifc

@@ -0,0 +1,97 @@
+ISO-10303-21;
+HEADER;
+FILE_DESCRIPTION(('ViewDefinition[DesignTransferView]'),'2;1');
+FILE_NAME('IfcParseExamples_test.ifc','2025-12-12T13:49:19+05:00',(''),(''),'IfcOpenShell 0.0.0','Bonsai 0.8.5-alpha251212-a47cbc3','Nobody');
+FILE_SCHEMA(('IFC2X3'));
+ENDSEC;
+DATA;
+#1=IFCPERSON('HSeldon','Seldon','Hari',$,$,$,$,$);
+#2=IFCORGANIZATION('APTR','Aperture Science',$,$,$);
+#3=IFCPERSONANDORGANIZATION(#1,#2,$);
+#4=IFCACTORROLE(.USERDEFINED.,'CONTRIBUTOR',$);
+#5=IFCORGANIZATION('IfcOpenShell','IfcOpenShell','IfcOpenShell is an open source software library that helps users and software developers to work with IFC data.',(#4),(#6));
+#6=IFCTELECOMADDRESS(.USERDEFINED.,$,'WEBPAGE',$,$,$,$,'https://ifcopenshell.org');
+#7=IFCAPPLICATION(#5,'0.8.5','Bonsai','Bonsai-0.8.5');
+#8=IFCOWNERHISTORY(#3,#7,.READWRITE.,.ADDED.,1765520605,#3,#7,1765520605);
+#9=IFCPROJECT('3GSSvm5SP5U96O5iar8uYb',#8,'My Project',$,$,$,$,(#22,#34),#17);
+#10=IFCSIUNIT(*,.LENGTHUNIT.,$,.METRE.);
+#11=IFCSIUNIT(*,.AREAUNIT.,$,.SQUARE_METRE.);
+#12=IFCSIUNIT(*,.VOLUMEUNIT.,$,.CUBIC_METRE.);
+#13=IFCDIMENSIONALEXPONENTS(0,0,0,0,0,0,0);
+#14=IFCSIUNIT(*,.PLANEANGLEUNIT.,$,.RADIAN.);
+#15=IFCMEASUREWITHUNIT(IFCREAL(0.0174532925199433),#14);
+#16=IFCCONVERSIONBASEDUNIT(#13,.PLANEANGLEUNIT.,'degree',#15);
+#17=IFCUNITASSIGNMENT((#12,#10,#16,#11));
+#18=IFCCARTESIANPOINT((0.,0.,0.));
+#19=IFCDIRECTION((0.,0.,1.));
+#20=IFCDIRECTION((1.,0.,0.));
+#21=IFCAXIS2PLACEMENT3D(#18,#19,#20);
+#22=IFCGEOMETRICREPRESENTATIONCONTEXT($,'Model',3,1.E-05,#21,$);
+#23=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Body','Model',*,*,*,*,#22,$,.MODEL_VIEW.,$);
+#24=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Axis','Model',*,*,*,*,#22,$,.GRAPH_VIEW.,$);
+#25=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Box','Model',*,*,*,*,#22,$,.MODEL_VIEW.,$);
+#26=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Annotation','Model',*,*,*,*,#22,$,.SECTION_VIEW.,$);
+#27=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Annotation','Model',*,*,*,*,#22,$,.ELEVATION_VIEW.,$);
+#28=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Annotation','Model',*,*,*,*,#22,$,.MODEL_VIEW.,$);
+#29=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Annotation','Model',*,*,*,*,#22,$,.PLAN_VIEW.,$);
+#30=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Profile','Model',*,*,*,*,#22,$,.ELEVATION_VIEW.,$);
+#31=IFCCARTESIANPOINT((0.,0.));
+#32=IFCDIRECTION((1.,0.));
+#33=IFCAXIS2PLACEMENT2D(#31,#32);
+#34=IFCGEOMETRICREPRESENTATIONCONTEXT($,'Plan',2,1.E-05,#33,$);
+#35=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Axis','Plan',*,*,*,*,#34,$,.GRAPH_VIEW.,$);
+#36=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Body','Plan',*,*,*,*,#34,$,.PLAN_VIEW.,$);
+#37=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Annotation','Plan',*,*,*,*,#34,$,.PLAN_VIEW.,$);
+#38=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Annotation','Plan',*,*,*,*,#34,$,.REFLECTED_PLAN_VIEW.,$);
+#39=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765520605,#3,#7,1765520605);
+#40=IFCSITE('2Ys4j4OOf3x9UYeALDJ_g3',#39,'My Site',$,$,#66,$,$,.ELEMENT.,$,$,$,$,$);
+#46=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765520605,#3,#7,1765520605);
+#47=IFCBUILDING('3e580MQFTCD9tCSaZWRPi9',#46,'My Building',$,$,#73,$,$,.ELEMENT.,$,$,$);
+#53=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765520605,#3,#7,1765520605);
+#54=IFCBUILDINGSTOREY('3XFkAr6KbAsP5wR3gxi3my',#53,'My Storey',$,$,#80,$,$,.ELEMENT.,$);
+#60=IFCOWNERHISTORY(#3,#7,.READWRITE.,.ADDED.,1765520605,#3,#7,1765520605);
+#61=IFCRELAGGREGATES('2OWfFyDQn0qP0Vd6NWGX7k',#60,$,$,#9,(#40));
+#62=IFCCARTESIANPOINT((0.,0.,0.));
+#63=IFCDIRECTION((0.,0.,1.));
+#64=IFCDIRECTION((1.,0.,0.));
+#65=IFCAXIS2PLACEMENT3D(#62,#63,#64);
+#66=IFCLOCALPLACEMENT($,#65);
+#67=IFCOWNERHISTORY(#3,#7,.READWRITE.,.ADDED.,1765520605,#3,#7,1765520605);
+#68=IFCRELAGGREGATES('3_X_vfPpXDaO3NODBJgmSp',#67,$,$,#40,(#47));
+#69=IFCCARTESIANPOINT((0.,0.,0.));
+#70=IFCDIRECTION((0.,0.,1.));
+#71=IFCDIRECTION((1.,0.,0.));
+#72=IFCAXIS2PLACEMENT3D(#69,#70,#71);
+#73=IFCLOCALPLACEMENT(#66,#72);
+#74=IFCOWNERHISTORY(#3,#7,.READWRITE.,.ADDED.,1765520605,#3,#7,1765520605);
+#75=IFCRELAGGREGATES('3ScF98CZD3pAa0SW$mhBHF',#74,$,$,#47,(#54));
+#76=IFCCARTESIANPOINT((0.,0.,0.));
+#77=IFCDIRECTION((0.,0.,1.));
+#78=IFCDIRECTION((1.,0.,0.));
+#79=IFCAXIS2PLACEMENT3D(#76,#77,#78);
+#80=IFCLOCALPLACEMENT(#73,#79);
+#110=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765529359,#3,#7,1765520632);
+#111=IFCWALL('1lfiJzSCH1a8vjDuSLL4Ii',#110,'Cube',$,$,#203,$,$);
+#112=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765520818,#3,#7,1765520632);
+#113=IFCRELCONTAINEDINSPATIALSTRUCTURE('2Gqx6vP7jB4x_h65Tawn0f',#112,$,$,(#111,#182,#150),#54);
+#149=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765529359,#3,#7,1765520810);
+#150=IFCWINDOW('1eE0btB_54tBL59wLXKO1B',#149,'Cube',$,$,#208,$,$,$,$);
+#181=IFCOWNERHISTORY(#3,#7,.READWRITE.,.MODIFIED.,1765529359,#3,#7,1765520818);
+#182=IFCBUILDINGELEMENTPART('0fmaoBJgz0kPBavO$EJkPn',#181,'Cube',$,$,#198,$,$);
+#194=IFCCARTESIANPOINT((-3.82147288322449,-0.987768530845642,1.78445267677307));
+#195=IFCDIRECTION((0.,0.,1.));
+#196=IFCDIRECTION((1.,0.,0.));
+#197=IFCAXIS2PLACEMENT3D(#194,#195,#196);
+#198=IFCLOCALPLACEMENT(#80,#197);
+#199=IFCCARTESIANPOINT((0.,0.,0.));
+#200=IFCDIRECTION((0.,0.,1.));
+#201=IFCDIRECTION((1.,0.,0.));
+#202=IFCAXIS2PLACEMENT3D(#199,#200,#201);
+#203=IFCLOCALPLACEMENT(#80,#202);
+#204=IFCCARTESIANPOINT((0.,4.25822639465332,0.));
+#205=IFCDIRECTION((0.,0.,1.));
+#206=IFCDIRECTION((1.,0.,0.));
+#207=IFCAXIS2PLACEMENT3D(#204,#205,#206);
+#208=IFCLOCALPLACEMENT(#80,#207);
+ENDSEC;
+END-ISO-10303-21;

src/examples/README.md

@@ -0,0 +1,22 @@
+
+Example of building IfcParseExamples outside of the IfcOpenShell build tree.
+
+```powershell
+$IFCOPENSHELL_ROOT="L:\Projects\Github\IfcOpenShell"
+$PREFIX_PATH="$IFCOPENSHELL_ROOT\_deps\boost_1_86_0\stage\vs2022-x64"
+$PREFIX_PATH+=";$IFCOPENSHELL_ROOT\_installed-vs2022-x64"
+$PREFIX_PATH+=";$IFCOPENSHELL_ROOT\_deps-vs2022-x64-installed\rocksdb"
+$PREFIX_PATH+=";$IFCOPENSHELL_ROOT\_deps-vs2022-x64-installed\zstd"
+$PREFIX_PATH+=";L:\Software\usr\libxml2"
+
+cmake .. -G Ninja -DCMAKE_PREFIX_PATH="$PREFIX_PATH" -DCMAKE_BUILD_TYPE=Release
+ninja -v
+./IfcParseExamples.exe "../IfcParseExamples_test.ifc"
+# Scanning file...
+# Done scanning file
+# Done resolving references
+# Found 3 elements in ..\IfcParseExamples_test.ifc:
+# #182=IfcBuildingElementPart('0fmaoBJgz0kPBavO$EJkPn',#181,'Cube',$,$,#193,#183,$)
+# #111=IfcWall('1lfiJzSCH1a8vjDuSLL4Ii',#110,'Cube',$,$,#119,#114,$)
+# #150=IfcWindow('1eE0btB_54tBL59wLXKO1B',#149,'Cube',$,$,#188,#151,$,$,$)
+```