ci: Don't use libobs-dev on Ubuntu

The provided libobs-dev does not match CMake standards (LibObs instead of libobs like on all other platforms). It also does not provide the obs-frontend-api, or any other required files.

.github/workflows/main.yml

@@ -432,11 +432,42 @@ jobs:
         sudo apt-get -y install -V \
           libavcodec-dev libavdevice-dev libavfilter-dev libavformat-dev libavutil-dev libswresample-dev libswscale-dev \
           libcurl4-openssl-dev
+    - name: "Dependency: OBS Libraries (Cache)"
+      id: obs-cache
+      uses: actions/cache@v3
+      with:
+        path: "${{ github.workspace }}/build/obs"
+        key: "obs${{ env.obs_version }}-${{ matrix.runner }}-${{ env.CACHE_VERSION }}"
     - name: "Dependency: OBS Libraries"
       id: obs
+      if: ${{ steps.obs-cache.outputs.cache-hit != 'true' }}
       shell: bash
       run: |
-        sudo apt-get install libobs-dev
+        # Extra requirements by libobs on Linux.
+        sudo apt-get install \
+          libavcodec-dev libavdevice-dev libavfilter-dev libavformat-dev libavutil-dev libswresample-dev libswscale-dev \
+          libx264-dev libcurl4-openssl-dev libmbedtls-dev libgl1-mesa-dev libjansson-dev libluajit-5.1-dev python3-dev \
+          libx11-dev libxcb-randr0-dev libxcb-shm0-dev libxcb-xinerama0-dev libxcomposite-dev libxinerama-dev \
+          libxcb1-dev libx11-xcb-dev libxcb-xfixes0-dev swig libcmocka-dev libxss-dev libglvnd-dev libgles2-mesa \
+          libgles2-mesa-dev libwayland-dev \
+          libasound2-dev libfdk-aac-dev libfontconfig-dev libfreetype6-dev libjack-jackd2-dev libpulse-dev \
+          libsndio-dev libspeexdsp-dev libudev-dev libv4l-dev libva-dev libvlc-dev libdrm-dev
+        cmake \
+          -S "${{ github.workspace }}/third-party/obs-studio" \
+          -B "${{ github.workspace }}/build/obs" \
+          -DCMAKE_INSTALL_PREFIX="${{ github.workspace }}/build/obs/install" \
+          -DCMAKE_PREFIX_PATH="${{ github.workspace }}/build/obsdeps;${{ github.workspace }}/build/qt" \
+          -DENABLE_PLUGINS=OFF \
+          -DENABLE_UI=OFF \
+          -DENABLE_SCRIPTING=OFF
+        cmake \
+          --build "${{ github.workspace }}/build/obs" \
+          --config Release \
+          --target obs-frontend-api
+        cmake \
+          --install "${{ github.workspace }}/build/obs" \
+          --config Release \
+          --component obs_libraries
     - name: "Configure"
       continue-on-error: true
       shell: bash
@@ -444,12 +475,10 @@ jobs:
         cmake \
           -S "${{ github.workspace }}" \
           -B "${{ github.workspace }}/build/ci" \
-          ${{ env.cmake_generator }} \
+          -DCMAKE_INSTALL_PREFIX="${{ github.workspace }}/build/ci/install" \
-          ${{ env.cmake_generator_toolset }} \
-          ${{ env.cmake_generator_platform }} \
           -DPACKAGE_NAME="streamfx-${{ matrix.package_name }}" \
           -DPACKAGE_PREFIX="${{ github.workspace }}/build/package" \
-          -Dlibobs_DIR="/usr/lib/x86_64-linux-gnu/cmake/"
+          -Dlibobs_DIR="${{ github.workspace }}/build/obs/install"
     - name: "Build: Debug"
       continue-on-error: true
       shell: bash