Compile support for iOS & Android about flecs.net

[BeanCheeseBurrito]

IOS static libraries were added in the latest package pushed to the GitLab feed. https://gitlab.com/BeanCheeseBurrito/Flecs.NET/-/packages/20154174

[BeanCheeseBurrito]

I will look into adding them!

[BeanCheeseBurrito]

Flecs.NET uses zig to cross-compile native libraries for all target platforms. Trying to compile flecs with -Dtarget=aarch64-linux-android or -Dtarget=aarch64-ios doesn't seem to work out of the box due to missing headers. I'm assuming zig doesn't include them for those targets.

fatal error: 'assert.h' file not found

I'm not familiar enough with c/c++ and mobile development to get the build script to compile for those platforms but I'm open to contributions if anyone knows how to get it working. These are the relevant files for anyone interested in adding support for mobile targets.

https://github.com/BeanCheeseBurrito/Flecs.NET/blob/main/src/Flecs.NET.Native/build.zig
https://github.com/BeanCheeseBurrito/Flecs.NET/blob/main/src/Flecs.NET.Native/Flecs.NET.Native.csproj

[oix7]

Thanks! Can we avoid exotic targets like linux android for now and just add the more vanilla stuff that zig does support? Or for modern ios at least?
ziglang/zig#5145

[oix7]

• and maybe skip the ios simulator target too for simplicity, although it seems someone has done it before: https://github.com/kubkon/zig-ios-example

[BeanCheeseBurrito]

Thanks! Can we avoid exotic targets like linux android for now and just add the more vanilla stuff that zig does support? Or for modern ios at least? ziglang/zig#5145

Zig doesn't provide(?) the headers needed to cross-compile for android and ios. The build script needs to be changed to allow the user to manually provide them but I'm not experienced enough with mobile development to set it up myself.

[oix7]

In case it helps, I made this example github action that will output a static library via https://github.com/leetal/ios-cmake without needing any code signing.

name: Build Flecs for iOS

on:
  push:
    tags:
      - 'v*'
  workflow_dispatch:

jobs:
  build:
    runs-on: macos-latest
    strategy:
      matrix:
        config: [Debug, Release]
    steps:
      - name: Checkout code
        uses: actions/checkout@v2
        
      - name: Setup environment
        run: |
          echo "FLECS_REPO=https://github.com/SanderMertens/flecs.git" >> $GITHUB_ENV
          echo "FLECS_DIR=$GITHUB_WORKSPACE/flecs" >> $GITHUB_ENV
          echo "DEBUG_DIR=$GITHUB_WORKSPACE/build_ios/debug" >> $GITHUB_ENV
          echo "RELEASE_DIR=$GITHUB_WORKSPACE/build_ios/release" >> $GITHUB_ENV
          echo "TOOLCHAIN_FILE=$GITHUB_WORKSPACE/ios.toolchain.cmake" >> $GITHUB_ENV
          
      - name: Clone Flecs Repository
        run: git clone ${{ env.FLECS_REPO }} ${{ env.FLECS_DIR }}
          
      - name: Download dependencies
        run: |
          if [ ! -f "$TOOLCHAIN_FILE" ]; then
            curl -O https://raw.githubusercontent.com/leetal/ios-cmake/master/ios.toolchain.cmake
          fi
          
      - name: Build static library
        run: |
          mkdir -p $DEBUG_DIR
          mkdir -p $RELEASE_DIR
          cd $DEBUG_DIR
          cmake -DCMAKE_BUILD_TYPE=Debug $FLECS_DIR
          make
          mv libflecs_static.a libflecs.a
          cd $RELEASE_DIR
          cmake -DCMAKE_BUILD_TYPE=Release $FLECS_DIR
          make
          mv libflecs_static.a libflecs.a
          
      - name: Upload artifact (Debug)
        if: matrix.config == 'Debug'
        uses: actions/upload-artifact@v2
        with:
          name: libflecs-debug
          path: ${{ env.DEBUG_DIR }}/libflecs.a
          
      - name: Upload artifact (Release)
        if: matrix.config == 'Release'
        uses: actions/upload-artifact@v2
        with:
          name: libflecs-release
          path: ${{ env.RELEASE_DIR }}/libflecs.a