Merge branch 'wasm-ci' into 'master'

Wasm ci

See merge request vtk/vtk-examples!321

.gitlab-ci.yml

+stages:
+    - prep
+    - build
+    - deploy
+
+default:
+    image: ubuntu:22.04
+    tags:
+        - linux-x86_64
+        - build
+        - vtk-examples
+    artifacts:
+        expire_in: 1 day
+
+build-vtk:
+    image: $CI_REGISTRY/vtk/vtk-examples:20240119
+    stage: prep
+    cache:
+        key: vtk-cache
+        paths:
+            - vtk
+        policy: pull-push
+    script:
+        - bash .gitlab/ci/scripts/build_vtk.sh
+    artifacts:
+        paths: 
+            - vtk
+
+package-data:
+    image: $CI_REGISTRY/vtk/vtk-examples:20240119
+    stage: build
+    script:
+        - bash .gitlab/ci/scripts/package_data.sh
+    artifacts:
+        paths:
+            - packaged_data/
+
+build-examples:
+    image: $CI_REGISTRY/vtk/vtk-examples:20240119
+    stage: build
+    script:
+        - bash .gitlab/ci/scripts/build_examples.sh
+    artifacts:
+        paths:
+            - build_examples/
+
+
+build-gh-pages:
+    rules:
+        - if: '$CI_COMMIT_REF_NAME == "master"'
+    stage: build
+    before_script:
+        - bash .gitlab/ci/scripts/before_build_gh-pages.sh
+    script:
+        - eval $(ssh-agent -s)
+        - ssh-add $GH_KEY
+        - bash .gitlab/ci/scripts/build_gh-pages.sh
+    environment:
+        name: deploy-gh-pages
+        url: https://github.com/Kitware/vtk-examples
+
+
+deploy-examples:
+    rules:
+        - if: '$CI_COMMIT_REF_NAME == "master"'
+    needs:
+        - build-examples
+    stage: deploy
+    dependencies:
+        - build-examples
+    before_script:
+        - bash .gitlab/ci/scripts/before_deploy_examples.sh
+    script:
+        - eval $(ssh-agent -s)
+        - ssh-add $RSYNC_KEY
+        - bash .gitlab/ci/scripts/deploy_examples.sh
+    environment:
+        name: deploy-examples
+        url: https://web.kitware.com
+
+deploy-data:
+    rules:
+        - if: '$CI_COMMIT_REF_NAME == "master"'
+    needs:
+        - package-data
+    stage: deploy
+    dependencies:
+        - package-data
+    before_script:
+        - bash .gitlab/ci/scripts/before_deploy_data.sh
+    script:
+        - eval $(ssh-agent -s)
+        - ssh-add $RSYNC_KEY
+        - bash .gitlab/ci/scripts/deploy_data.sh
+    environment:
+        name: deploy-examples
+        url: https://web.kitware.com

.gitlab/GenerateHtmlCMake.py

+import argparse
+import json
+import shutil
+import subprocess
+import os
+
+def GetParameters():
+    parser = argparse.ArgumentParser(description='', epilog='')
+    parser.add_argument('source_path')
+    parser.add_argument('dest_path')
+    parser.add_argument('vtk_source_path')
+    args = parser.parse_args()
+    return args.source_path, args.dest_path, args.vtk_source_path
+
+def GenerateExample(example_name, source_path, dest_path, vtk_source_path):
+    shutil.copyfile('.gitlab/templates/index.html.template', os.path.join(dest_path, 'index.html'))
+    with open(os.path.join(dest_path, 'index.html'), 'r') as index:
+        data = index.read()
+    data = data.replace('XXX', example_name)
+    with open(os.path.join(dest_path, 'index.html'), 'w') as index:
+        index.write(data)
+    shutil.copyfile('.gitlab/templates/CMakeLists.txt.template', os.path.join(dest_path, 'CMakeLists.txt'))
+    with open(os.path.join(dest_path, 'CMakeLists.txt'), 'r') as cmake:
+        data = cmake.read()
+    data = data.replace('XXX', example_name)
+    try:
+        process = subprocess.run('python3 .gitlab/WhatModulesVTK.py ' + vtk_source_path + ' ' + source_path, shell=True, check=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        result = process.stdout.decode('utf-8')
+    except subprocess.CalledProcessError as err:
+        print('ERROR:', err)
+        if err.returncode != 0:
+            print('returncode:', err.returncode)
+            print('Have {} bytes in stdout:\n{}'.format(
+                    len(err.stdout),
+                    err.stdout.decode('utf-8'))
+                        )
+            print('Have {} bytes in stderr:\n{}'.format(
+                    len(err.stderr),
+                    err.stderr.decode('utf-8'))
+                        )
+        result = f"# The following error occurred running {err.cmd}\n"
+        for line in err.stderr.decode('utf-8').split('\n'):
+            result += f"# {line}\n"
+    data = data.replace('ZZZ', result)
+    with open(os.path.join(dest_path, 'CMakeLists.txt'), 'w') as cmake:
+        cmake.write(data)
+
+def GenerateExampleArgs(example_name, source_path, dest_path, vtk_source_path, args_data):
+    shutil.copyfile('.gitlab/templates/index_arguments.html.template', os.path.join(dest_path, 'index.html'))
+    with open(os.path.join(dest_path, 'index.html'), 'r') as index:
+        data = index.read()
+    data = data.replace('XXX', example_name)
+    module_arguments = []
+    for arg in args_data.get('args'):
+        module_arguments.append(arg)
+    data = data.replace('YYY', '\', \''.join(module_arguments))
+
+    script_lines = []
+    for file in args_data.get('files'):
+        script_lines.append('<script type="text/javascript" src="https://vtk.org/files/examples/data/' + file + '.js"></script>')
+    data = data.replace('ZZZ', '\n'.join(script_lines))
+
+    with open(os.path.join(dest_path, 'index.html'), 'w') as index:
+        index.write(data)
+    shutil.copyfile('.gitlab/templates/CMakeLists_arguments.txt.template', os.path.join(dest_path, 'CMakeLists.txt'))
+    with open(os.path.join(dest_path, 'CMakeLists.txt'), 'r') as cmake:
+        data = cmake.read()
+    data = data.replace('XXX', example_name)
+    try:
+        process = subprocess.run('python3 .gitlab/WhatModulesVTK.py ' + vtk_source_path + ' ' + source_path, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        result = process.stdout.decode('utf-8')
+    except subprocess.CalledProcessError as err:
+        print('ERROR:', err)
+        if err.returncode != 0:
+            print('returncode:', err.returncode)
+            print('Have {} bytes in stdout:\n{}'.format(
+                    len(err.stdout),
+                    err.stdout.decode('utf-8'))
+                        )
+            print('Have {} bytes in stderr:\n{}'.format(
+                    len(err.stderr),
+                    err.stderr.decode('utf-8'))
+                        )
+        result = f"# The following error occurred running {err.cmd}\n"
+        for line in err.stderr.decode('utf-8').split('\n'):
+            result += f"# {line}\n"
+    data = data.replace('ZZZ', result)
+
+    with open(os.path.join(dest_path, 'CMakeLists.txt'), 'w') as cmake:
+        cmake.write(data)
+
+
+def main():
+    source_path, dest_path, vtk_source_path = GetParameters()
+    example_name = os.path.splitext(os.path.basename(source_path))[0]
+    with open('src/Admin/WASM/ArgsNeeded.json') as f:
+        data = json.load(f)
+    if data.get(example_name, None):
+        print('arguments found')
+        GenerateExampleArgs(example_name, source_path, dest_path, vtk_source_path, data.get(example_name))
+    else:
+        print('no arguments found')
+        GenerateExample(example_name, source_path, dest_path, vtk_source_path)
+
+if __name__ == '__main__':
+    main()

.gitlab/GenerateSuperCMake.py

+import shutil
+import glob
+
+shutil.copyfile('.gitlab/templates/CMakeLists_global.txt.template', 'pregen_examples/CMakeLists.txt')
+with open('pregen_examples/CMakeLists.txt', 'r') as cmake:
+    data = cmake.read()
+
+subdirectories = []
+for path in glob.glob('pregen_examples/**/CMakeLists.txt', recursive=True):
+    if path != 'pregen_examples/CMakeLists.txt':
+        subdirectories.append('add_subdirectory(' + path.removeprefix('pregen_examples/').removesuffix('CMakeLists.txt') + ')')
+data = data.replace('XXX', '\n'.join(subdirectories))
+
+with open('pregen_examples/CMakeLists.txt', 'w') as cmake:
+    cmake.write(data)

.gitlab/WhatModulesVTK.py

+#!/usr/bin/env python
+
+import re
+import sys
+from collections import defaultdict
+from pathlib import Path
+
+def remove_prefix(text, prefix):
+    if sys.version_info > (3, 9):
+        return text.removeprefix(prefix)
+    else:
+        if text.startswith(prefix): # only modify the text if it starts with the prefix
+            text = text.replace(prefix, "", 1) # remove one instance of prefix
+        return text
+
+def get_program_parameters():
+    import argparse
+    description = 'Generate a find_package(VTK COMPONENTS ...) that lists all modules referenced by a set of files.'
+    epilogue = '''
+This uses the VTK source folder to determine the modules and headers.
+Then the user files/folders are looked at to find the headers being used.
+Finally a find_package() is output with the modules you need for
+ inclusion in your CMakeLists.txt file.
+
+Note:
+1) If include file(s) are not found when building your application.
+    You may need to search the VTK source to find where the file is.
+    Then look at contents of vtk.module in that folder and add the
+     module name to the find_package statement. 
+2) If linking fails, it usually means that the needed module has not been
+     built, so you may need to add it to your VTK build and rebuild VTK.
+3) More modules than strictly necessary may be included.     
+    '''
+    parser = argparse.ArgumentParser(description=description, epilog=epilogue,
+                                     formatter_class=argparse.RawDescriptionHelpFormatter)
+    parser.add_argument('vtk_path', help='The path to the VTK source tree.')
+    parser.add_argument('application', nargs='+', help='Paths to the application files or folders.')
+    args = parser.parse_args()
+    return args.vtk_path, args.application
+
+
+def check_paths(vtk_src_dir, application_srcs):
+    """
+    Check that the paths are valid.
+
+    :param vtk_src_dir: The path to the VTK source.
+    :param application_srcs: The user source files to be scanned for modules.
+    :return: True if paths, files exist.
+    """
+    ok = True
+    if not Path(vtk_src_dir).is_dir():
+        print('The path to your VTK Source folder does not exist.')
+        print(Path(vtk_src_dir))
+        ok = False
+    bad_paths = list()
+    for f in application_srcs:
+        p = Path(f)
+        if not (p.is_dir() or p.is_file()):
+            bad_paths.append(p)
+    if bad_paths:
+        print('These application paths or files do not exist.')
+        for p in bad_paths:
+            print(p)
+            ok = False
+    return ok
+
+
+def find_vtk_modules(vtk_src_dir):
+    """
+    Build a dict of the VTK Module name, library name(if it exists) and any header files.
+
+    :param vtk_src_dir: The path to the VTK source folder
+    :return: Module name, library name and headers.
+    """
+    vtk_modules = defaultdict(dict)
+    modules = [f for f in Path(vtk_src_dir).rglob('vtk.module')]
+    # Includes in the module path
+    file_patterns = ['vtk*.h', 'vtk*.h.in', 'QVTK*.h', '*QtQuick.h']
+    for module in modules:
+        content = module.read_text()
+        args = content.split('\n')
+        #  Assuming NAME is always there.
+        if 'NAME' in args:
+            name = args[args.index('NAME') + 1].strip()
+            if 'LIBRARY_NAME' in args:
+                library_name = args[args.index('LIBRARY_NAME') + 1].strip()
+            else:
+                library_name = None
+            headers = list()
+            for pattern in file_patterns:
+                if pattern == 'vtk*.h.in':
+                    # These files will be converted to header files in the build folder of VTK.
+                    headers.extend([f.with_suffix('').name for f in module.parent.glob(pattern)])
+                else:
+                    headers.extend([f.name for f in module.parent.glob(pattern)])
+            vtk_modules[name]['library_name'] = library_name
+            vtk_modules[name]['headers'] = headers
+    return vtk_modules
+
+
+def build_headers_modules(modules):
+    """
+    Make a dictionary whose key is the header filename and value is the module.
+
+    :param modules: The modules.
+    :return: Headers and their corresponding module.
+    """
+    # The headers should be unique to a module, however we will not assume this.
+    headers_modules = defaultdict(set)
+    for k, v in modules.items():
+        if 'headers' in v:
+            for k1 in v['headers']:
+                headers_modules[k1].add(k)
+    return headers_modules
+
+
+def find_application_includes(path):
+    """
+    Build a set that contains the vtk includes found in the file.
+
+    :param path: The path to the application file.
+    :return: The includes that were found.
+    """
+    includes = set()
+    include_hdr1 = re.compile(r'((?:vtk|QVTK).*\.h)')
+    include_hdr2 = re.compile(r'(\w+QtQuick\.h)')
+    content = path.read_text()
+    incs = include_hdr1.findall(content)
+    includes.update(incs)
+    incs = include_hdr2.findall(content)
+    includes.update(incs)
+    return includes
+
+
+def generate_find_package(vtk_src_dir, application_srcs):
+    """
+    Generate the find_package statement.
+    
+    :param vtk_src_dir: The VTK source folder.
+    :param application_srcs: A list of application folders and or files.
+    :return: The find_package statement.
+    """
+    vtk_modules = find_vtk_modules(vtk_src_dir)
+    # Test to see if VTK source is provided
+    if len(vtk_modules) == 0:
+        print(vtk_src_dir, 'is not a VTK source directory. It does not contain any vtk.module files.')
+        return None
+    vtk_headers_modules = build_headers_modules(vtk_modules)
+
+    valid_extensions = ['.h', '.hxx', '.txx', '.cpp', '.cxx', '.cc']
+
+    # Build a set of includes for all command line files
+    all_includes = set()
+    for app_src in application_srcs:
+        p = Path(app_src)
+        if p.is_file():
+            if p.suffix in valid_extensions:
+                all_includes.update(find_application_includes(p))
+        elif p.is_dir():
+            paths = list()
+            for ext in valid_extensions:
+                paths.extend([f for f in p.rglob('*' + ext) if f.is_file()])
+            for path in paths:
+                all_includes.update(find_application_includes(path))
+    if len(all_includes) == 0:
+        print('No VTK includes found in the application files.')
+        return None
+
+    # Build a set that contains all modules referenced in the user files.
+    all_modules = set()
+    for inc in all_includes:
+        if inc in vtk_headers_modules:
+            for m in vtk_headers_modules[inc]:
+                all_modules.add(m)
+
+    if 'VTK::RenderingCore' in all_modules:
+        all_modules.add('VTK::RenderingOpenGL2')
+        all_modules.add('VTK::InteractionStyle')
+        all_modules.add('VTK::RenderingFreeType')
+        # all_modules.add('VTK::RenderingGL2PSOpenGL2')
+        all_modules.add('VTK::RenderingContextOpenGL2')
+    if 'VTK::DomainsChemistry' in all_modules:
+        all_modules.add('VTK::DomainsChemistryOpenGL2')
+    if 'VTK::RenderingVolume' in all_modules:
+        all_modules.add('VTK::RenderingVolumeOpenGL2')
+    if 'VTK::RenderingContext2D' in all_modules:
+        all_modules.add('VTK::RenderingContextOpenGL2')
+    if 'VTK::IOExport' in all_modules:
+        all_modules.add('VTK::IOExportOpenGL2')
+        all_modules.add('VTK::IOExportPDF')
+        all_modules.add('VTK::RenderingContextOpenGL2')
+
+    res = ['find_package(VTK', ' COMPONENTS']
+    for m in sorted(all_modules):
+        m = remove_prefix(m, 'VTK::')
+        res.append(' ' * 2 + m)
+    res.append('REQUIRED)')
+    return res
+
+
+def main():
+    vtk_src_dir, application_srcs = get_program_parameters()
+    if not check_paths(vtk_src_dir, application_srcs):
+        return
+
+    res = generate_find_package(vtk_src_dir, application_srcs)
+    if res:
+        print('\n'.join(res))
+
+
+if __name__ == '__main__':
+    main()

.gitlab/ci/docker/vtk-examples/Dockerfile

+FROM ubuntu:latest
+
+SHELL ["/bin/bash", "-c"]
+COPY install_deps.sh /
+RUN bash install_deps.sh
+COPY install_emsdk.sh /
+RUN bash install_emsdk.sh
+ENV PATH /emsdk:/emsdk/upstream/emscripten:/emsdk/node/16.20.0_64bit/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+ENV EMSDK /emsdk
+ENV EMSDK_NODE /emsdk/node/16.20.0_64bit/bin/node
+CMD /bin/bash

.gitlab/ci/docker/vtk-examples/install_deps.sh

+#!/bin/bash
+
+apt update -y
+apt upgrade -y
+apt install -y git python3 cmake git xz-utils ninja-build clang gcc unzip
+apt clean -y

.gitlab/ci/docker/vtk-examples/install_emsdk.sh

+#!/bin/bash
+
+git clone --depth 1 --branch 3.1.50 https://github.com/emscripten-core/emsdk.git
+cd emsdk
+./emsdk install 3.1.50
+./emsdk activate 3.1.50

.gitlab/ci/scripts/before_build_gh-pages.sh

+#!/bin/bash
+apt update -y
+apt install -y python3 python3-venv git openssh-client rsync
+python3 -m venv venv/vtk-examples-web
+mkdir -p ~/.ssh
+chmod 700 ~/.ssh
+cp "$SSH_KNOWN_HOSTS" ~/.ssh/known_hosts
+chmod 644 ~/.ssh/known_hosts
+chmod 400 $GH_KEY
+git config --global user.email kwrobot+vtk-examples@kitware.com
+git config --global user.name "Kitware Robot"

.gitlab/ci/scripts/before_deploy_data.sh

+#!/bin/bash
+apt update -y
+apt install -y rsync openssh-client
+mkdir -p ~/.ssh
+chmod 700 ~/.ssh
+cp "$SSH_KNOWN_HOSTS" ~/.ssh/known_hosts
+chmod 644 ~/.ssh/known_hosts
+chmod 400 $RSYNC_KEY

.gitlab/ci/scripts/before_deploy_examples.sh

+#!/bin/bash
+apt update -y
+apt install -y rsync openssh-client
+mkdir -p ~/.ssh
+chmod 700 ~/.ssh
+cp "$SSH_KNOWN_HOSTS" ~/.ssh/known_hosts
+chmod 644 ~/.ssh/known_hosts
+chmod 400 $RSYNC_KEY

.gitlab/ci/scripts/build_examples.sh

+#!/bin/bash
+exclude_dirs=(Deprecated Untested Databases Developers Snippets Qt)
+shopt -s extglob
+mkdir build_examples
+mkdir pregen_examples
+for topic in src/Cxx/*/; do
+    topic_name=$(basename ${topic})
+    if [[ ! $(echo ${exclude_dirs[@]} | grep -Fw ${topic_name}) ]]; then
+        for f in ${topic}/*.cxx; do
+            name=$(basename ${f} .cxx)
+            if ! grep -Fxq "$name" src/Admin/WASM/exclude_wasm.txt; then
+                echo ${name}
+                target_path=pregen_examples/${topic_name}/${name}
+                mkdir -p ${target_path}
+                cp ${f} ${target_path}
+                for addon_file in ${topic}/${name}.!(md); do
+                    cp ${addon_file} ${target_path}
+                done
+                python3 .gitlab/GenerateHtmlCMake.py ${f} ${target_path} vtk
+            fi
+        done
+    fi
+done
+python3 .gitlab/GenerateSuperCMake.py
+emcmake cmake -GNinja \
+    -DEMSCRIPTEN:Bool=true \
+    -DVTK_DIR=$CI_PROJECT_DIR/vtk/build \
+    -DDEBUGINFO=NONE \
+    -S pregen_examples -B build_examples
+cmake --build build_examples

.gitlab/ci/scripts/build_gh-pages.sh

+#!/bin/sh
+source venv/vtk-examples-web/bin/activate
+python -m pip install --upgrade pip
+pip install wheel
+pip install mkdocs-material htmlmin
+git clone git@github.com:Kitware/vtk-examples.git /pages
+pushd /pages
+git checkout gh-pages
+popd
+OLDHOME=${HOME}
+HOME=${PWD}
+src/SyncSiteWithRepo.sh https://gitlab.kitware.com/vtk/vtk-examples https://examples.vtk.org/site/ https://github.com/Kitware/vtk-examples /pages vtk
+HOME=${OLDHOME}
+pushd /pages
+git add .
+git commit -m "nightly update"
+git push

.gitlab/ci/scripts/build_vtk.sh

+#!/bin/bash
+if [ ! -d vtk ]; then
+    git clone https://gitlab.kitware.com/vtk/vtk.git
+    cd vtk
+    mkdir build
+    emcmake cmake \
+        -GNinja -DBUILD_SHARED_LIBS:BOOL=OFF \
+        -DCMAKE_BUILD_TYPE:STRING=Release \
+        -DVTK_ENABLE_LOGGING:BOOL=OFF \
+        -DVTK_ENABLE_WRAPPING:BOOL=OFF \
+        -DVTK_MODULE_ENABLE_VTK_cli11:STRING=YES \
+        -DVTK_MODULE_ENABLE_VTK_RenderingLICOpenGL2:STRING=DONT_WANT \
+        -DVTK_BUILD_TESTING=ON \
+        -S . -B build
+else
+    cd vtk
+    git pull
+fi
+cmake --build build

.gitlab/ci/scripts/deploy_data.sh

+#!/bin/bash
+for file in packaged_data/*; do
+    gzip ${file}
+    mv ${file}.gz ${file}
+done
+rsync -av packaged_data/ kitware@web.kitware.com:/data/

.gitlab/ci/scripts/deploy_examples.sh

+#!/bin/bash
+shopt -s extglob
+for topic in build_examples/!(CMakeFiles)/; do
+    for example in ${topic}/*/; do
+        mkdir ${example}/upload
+        example_name=$(basename ${example})
+        gzip ${example}/${example_name}.wasm
+        mv ${example}/${example_name}.wasm.gz ${example}/upload/${example_name}.wasm
+        gzip ${example}/${example_name}.js
+        mv ${example}/${example_name}.js.gz ${example}/upload/${example_name}.js
+        gzip ${example}/index.html
+        mv ${example}/index.html.gz ${example}/upload/index.html
+        rsync -r ${example}/upload/ kitware@web.kitware.com:/${example_name}/
+    done
+done

.gitlab/ci/scripts/package_data.sh

+#!/bin/bash
+for f in $(find src/SupplementaryData/Cxx -type f); do
+    if [[ "$f" == *.zip ]]; then
+        mkdir src/Testing/Data/$(basename $f .zip)
+        unzip $f -d src/Testing/Data/$(basename $f .zip)
+    else
+        cp $f src/Testing/Data
+    fi
+done
+mkdir packages_fs
+python3 .gitlab/make_packages.py
+mkdir packaged_data
+for f in packages_fs/*; do
+    filename=$(basename $f)
+    /emsdk/upstream/emscripten/tools/file_packager packaged_data/${filename}.data --preload $f@/ --js-output=packaged_data/${filename}.js
+done

.gitlab/make_packages.py

+import json
+import shutil
+import glob
+import os
+import errno
+
+with open('src/Admin/WASM/packaged_files.json') as f:
+    data = json.load(f)
+
+for package_attr, package_val in data.items():
+    os.makedirs('packages_fs/' + package_attr)
+    for filename_attr, filename_val in package_val.items():
+        if filename_val['type'] == 'dir':
+            os.makedirs('packages_fs/' + package_attr + '/' + filename_attr)
+            for target in filename_val['path']:
+                for globtarget in glob.glob('src/Testing/Data/' + target):
+                    try:
+                        shutil.copytree(globtarget, 'packages_fs/' + package_attr + '/' + filename_attr + '/' + os.path.basename(globtarget))
+                    except OSError as exc: # copy file or directory
+                        if exc.errno in (errno.ENOTDIR, errno.EINVAL):
+                            shutil.copy(globtarget, 'packages_fs/' + package_attr + '/' + filename_attr)
+                        elif exc.errno == errno.EEXIST:
+                            pass
+                        else: raise
+        else:
+            shutil.copy('src/Testing/Data/' + filename_val['path'][0], 'packages_fs/' + package_attr + '/' + filename_attr)

.gitlab/templates/CMakeLists.txt.template

+
+cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
+
+project(XXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+# # -----------------------------------------------------------------------------
+# # EMSCRIPTEN only
+# # -----------------------------------------------------------------------------
+
+if (NOT EMSCRIPTEN)
+  message("Skipping example: This needs to run inside an Emscripten build environment")
+  return ()
+endif ()
+
+# -----------------------------------------------------------------------------
+# Handle VTK dependency
+# -----------------------------------------------------------------------------
+
+ZZZ
+
+if (NOT VTK_FOUND)
+  message("Skipping example: ${VTK_NOT_FOUND_MESSAGE}")
+  return ()
+endif ()
+
+# -----------------------------------------------------------------------------
+# Compile example code
+# -----------------------------------------------------------------------------
+
+add_executable(XXX XXX.cxx)
+
+target_link_libraries(XXX
+  PRIVATE
+  ${VTK_LIBRARIES}
+)
+# -----------------------------------------------------------------------------
+
+# WebAssembly build options
+# -----------------------------------------------------------------------------
+set(emscripten_link_options)
+set(emscripten_compile_options)
+
+list(APPEND emscripten_link_options
+  "SHELL:-s WASM=1"
+  "SHELL:-s ALLOW_MEMORY_GROWTH=1"
+  "SHELL:-s STACK_SIZE=2mb"
+)
+
+set(emscripten_debug_options)
+set(DEBUGINFO "PROFILE" CACHE STRING "Type of debug info")
+set_property(CACHE DEBUGINFO PROPERTY
+  STRINGS
+    NONE              # -g0
+    READABLE_JS       # -g1
+    PROFILE           # -g2
+    DEBUG_NATIVE      # -g3
+)
+
+if(DEBUGINFO STREQUAL "NONE")
+  list(APPEND emscripten_debug_options
+    "-g0"
+  )
+elseif(DEBUGINFO STREQUAL "READABLE_JS")
+  list(APPEND emscripten_debug_options
+    "-g1"
+  )
+  list(APPEND emscripten_link_options
+    "SHELL:-s DEMANGLE_SUPPORT=1"
+  )
+elseif(DEBUGINFO STREQUAL "PROFILE")
+  list(APPEND emscripten_debug_options
+    "-g2"
+  )
+  list(APPEND emscripten_link_options
+    "SHELL:-s DEMANGLE_SUPPORT=1"
+  )
+elseif(DEBUGINFO STREQUAL "DEBUG_NATIVE")
+  list(APPEND emscripten_debug_options
+    "-g3"
+  )
+  list(APPEND emscripten_link_options
+    "SHELL:-s ASSERTIONS=1"
+    "SHELL:-s DEMANGLE_SUPPORT=1"
+  )
+endif()
+
+# -----------------------------------------------------------------------------
+# Build options
+# -----------------------------------------------------------------------------
+set(emscripten_optimizations)
+set(OPTIMIZE "SMALLEST_WITH_CLOSURE" CACHE STRING "Emscripten optimization")
+set_property(CACHE OPTIMIZE PROPERTY
+  STRINGS
+    NO_OPTIMIZATION       # -O0
+    LITTLE                # -O1
+    MORE                  # -O2
+    BEST                  # -O3
+    SMALL                 # -Os
+    SMALLEST              # -Oz
+    SMALLEST_WITH_CLOSURE # -Oz --closure 1
+)
+
+if(OPTIMIZE STREQUAL "NO_OPTIMIZATION")
+  list(APPEND emscripten_optimizations
+    "-O0"
+  )
+elseif(OPTIMIZE STREQUAL "LITTLE")
+  list(APPEND emscripten_optimizations
+    "-O1"
+  )
+elseif(OPTIMIZE STREQUAL "MORE")
+  list(APPEND emscripten_optimizations
+    "-O2"
+  )
+elseif(OPTIMIZE STREQUAL "BEST")
+  list(APPEND emscripten_optimizations
+    "-O3"
+  )
+elseif(OPTIMIZE STREQUAL "SMALL")
+  list(APPEND emscripten_optimizations
+    "-Os"
+  )
+elseif(OPTIMIZE STREQUAL "SMALLEST")
+  list(APPEND emscripten_optimizations
+    "-Oz"
+  )
+elseif(OPTIMIZE STREQUAL "SMALLEST_WITH_CLOSURE")
+  list(APPEND emscripten_optimizations
+    "-Oz"
+  )
+  list(APPEND emscripten_link_options
+    "--closure 1"
+  )
+endif()
+
+target_compile_options(XXX
+  PUBLIC
+    ${emscripten_compile_options}
+    ${emscripten_optimizations}
+    ${emscripten_debug_options}
+)
+
+target_link_options(XXX
+  PUBLIC
+    ${emscripten_link_options}
+    ${emscripten_optimizations}
+    ${emscripten_debug_options}
+)
+
+# -----------------------------------------------------------------------------
+# VTK modules initialization
+# -----------------------------------------------------------------------------
+
+vtk_module_autoinit(
+  TARGETS  XXX
+  MODULES  ${VTK_LIBRARIES}
+)
+
+# -----------------------------------------------------------------------------
+# Copy HTML to build directory
+# -----------------------------------------------------------------------------
+
+add_custom_command(
+  TARGET XXX
+  POST_BUILD
+  COMMAND
+    ${CMAKE_COMMAND} -E copy_if_different
+      "${CMAKE_CURRENT_SOURCE_DIR}/index.html"
+      $<TARGET_FILE_DIR:XXX>
+)

.gitlab/templates/CMakeLists_arguments.txt.template

+
+
+cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
+
+project(XXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+# # -----------------------------------------------------------------------------
+# # EMSCRIPTEN only
+# # -----------------------------------------------------------------------------
+
+if (NOT EMSCRIPTEN)
+  message("Skipping example: This needs to run inside an Emscripten build environment")
+  return ()
+endif ()
+
+# -----------------------------------------------------------------------------
+# Handle VTK dependency
+# -----------------------------------------------------------------------------
+
+ZZZ
+
+if (NOT VTK_FOUND)
+  message("Skipping example: ${VTK_NOT_FOUND_MESSAGE}")
+  return ()
+endif ()
+
+# -----------------------------------------------------------------------------
+# Compile example code
+# -----------------------------------------------------------------------------
+
+add_executable(XXX XXX.cxx)
+
+target_link_libraries(XXX
+  PRIVATE
+  ${VTK_LIBRARIES}
+)
+# -----------------------------------------------------------------------------
+
+# WebAssembly build options
+# -----------------------------------------------------------------------------
+set(emscripten_link_options)
+set(emscripten_compile_options)
+
+list(APPEND emscripten_link_options
+  "SHELL:-s WASM=1"
+  "SHELL:-s ALLOW_MEMORY_GROWTH=1"
+  "SHELL:-s STACK_SIZE=2mb"
+  "SHELL:-s FORCE_FILESYSTEM"
+)
+
+list(APPEND emscripten_compile_options
+  "SHELL:-std=c++17"
+)
+
+set(emscripten_debug_options)
+set(DEBUGINFO "PROFILE" CACHE STRING "Type of debug info")
+set_property(CACHE DEBUGINFO PROPERTY
+  STRINGS
+    NONE              # -g0
+    READABLE_JS       # -g1
+    PROFILE           # -g2
+    DEBUG_NATIVE      # -g3
+)
+
+if(DEBUGINFO STREQUAL "NONE")
+  list(APPEND emscripten_debug_options
+    "-g0"
+  )
+elseif(DEBUGINFO STREQUAL "READABLE_JS")
+  list(APPEND emscripten_debug_options
+    "-g1"
+  )
+  list(APPEND emscripten_link_options
+    "SHELL:-s DEMANGLE_SUPPORT=1"
+  )
+elseif(DEBUGINFO STREQUAL "PROFILE")
+  list(APPEND emscripten_debug_options
+    "-g2"
+  )
+  list(APPEND emscripten_link_options
+    "SHELL:-s DEMANGLE_SUPPORT=1"
+  )
+elseif(DEBUGINFO STREQUAL "DEBUG_NATIVE")
+  list(APPEND emscripten_debug_options
+    "-g3"
+  )
+  list(APPEND emscripten_link_options
+    "SHELL:-s ASSERTIONS=1"
+    "SHELL:-s DEMANGLE_SUPPORT=1"
+  )
+endif()
+
+# -----------------------------------------------------------------------------
+# Build options
+# -----------------------------------------------------------------------------
+set(emscripten_optimizations)
+set(OPTIMIZE "SMALLEST_WITH_CLOSURE" CACHE STRING "Emscripten optimization")
+set_property(CACHE OPTIMIZE PROPERTY
+  STRINGS
+    NO_OPTIMIZATION       # -O0
+    LITTLE                # -O1
+    MORE                  # -O2
+    BEST                  # -O3
+    SMALL                 # -Os
+    SMALLEST              # -Oz
+    SMALLEST_WITH_CLOSURE # -Oz --closure 1
+)
+
+if(OPTIMIZE STREQUAL "NO_OPTIMIZATION")
+  list(APPEND emscripten_optimizations
+    "-O0"
+  )
+elseif(OPTIMIZE STREQUAL "LITTLE")
+  list(APPEND emscripten_optimizations
+    "-O1"
+  )
+elseif(OPTIMIZE STREQUAL "MORE")
+  list(APPEND emscripten_optimizations
+    "-O2"
+  )
+elseif(OPTIMIZE STREQUAL "BEST")
+  list(APPEND emscripten_optimizations
+    "-O3"
+  )
+elseif(OPTIMIZE STREQUAL "SMALL")
+  list(APPEND emscripten_optimizations
+    "-Os"
+  )
+elseif(OPTIMIZE STREQUAL "SMALLEST")
+  list(APPEND emscripten_optimizations
+    "-Oz"
+  )
+elseif(OPTIMIZE STREQUAL "SMALLEST_WITH_CLOSURE")
+  list(APPEND emscripten_optimizations
+    "-Oz"
+  )
+  list(APPEND emscripten_link_options
+    "--closure 1"
+  )
+endif()
+
+target_compile_options(XXX
+  PUBLIC
+    ${emscripten_compile_options}
+    ${emscripten_optimizations}
+    ${emscripten_debug_options}
+)
+
+target_link_options(XXX
+  PUBLIC
+    ${emscripten_link_options}
+    ${emscripten_optimizations}
+    ${emscripten_debug_options}
+)
+
+# -----------------------------------------------------------------------------
+# VTK modules initialization
+# -----------------------------------------------------------------------------
+
+vtk_module_autoinit(
+  TARGETS  XXX
+  MODULES  ${VTK_LIBRARIES}
+)
+
+# -----------------------------------------------------------------------------
+# Copy HTML to build directory
+# -----------------------------------------------------------------------------
+
+add_custom_command(
+  TARGET XXX
+  POST_BUILD
+  COMMAND
+    ${CMAKE_COMMAND} -E copy_if_different
+      "${CMAKE_CURRENT_SOURCE_DIR}/index.html"
+      $<TARGET_FILE_DIR:XXX>
+)

.gitlab/templates/CMakeLists_global.txt.template

+cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
+
+project(vtk-examples)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+XXX