raylib: add PLATFORM_OFFSCREEN support (#38)

* raylib: add PLATFORM_OFFSCREEN support for headless CI rendering

- build.sh: use commaai/raylib platform-offscreen commit, build offscreen
  variant (libraylib_offscreen.a) alongside desktop for x86_64, bundle
  GLVND dispatchers (libEGL, libOpenGL, libGLdispatch) in install/lib/mesa/
- build.py: add PLATFORM_OFFSCREEN elif — uses offscreen lib + bundled
  GLVND with RPATH, links -lOpenGL -lEGL instead of -lGL -lX11
- __init__.py: auto-rebuild CFFI when RAYLIB_PLATFORM env changes
  (tracks built platform in .raylib_platform marker file)
- Bump version to 5.5.0.5

This lets openpilot CI render headlessly via EGL surfaceless + Mesa
llvmpipe without needing xvfb or any additional apt packages.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* raylib: auto-detect CI and use PLATFORM_OFFSCREEN

__init__.py now auto-detects CI on Linux x86_64 and uses
PLATFORM_OFFSCREEN + LIBGL_ALWAYS_SOFTWARE=1 automatically.
No env vars needed in the consuming CI workflow.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

raylib/build.sh

@@ -33,6 +33,15 @@ if [[ "$(uname)" == "Linux" ]]; then
         sudo apt-get update && sudo apt-get install -y libdrm-dev libgbm-dev libgles2-mesa-dev libegl1-mesa-dev || true
       fi
     fi
+  elif [ "$RAYLIB_PLATFORM" = "PLATFORM_OFFSCREEN" ]; then
+    # offscreen (CI): needs EGL/GL dev packages (no X11)
+    if command -v apt-get &>/dev/null; then
+      if [ "$(id -u)" -eq 0 ]; then
+        apt-get update && apt-get install -y libegl-dev libgl-dev
+      else
+        sudo apt-get update && sudo apt-get install -y libegl-dev libgl-dev
+      fi
+    fi
   else
     # desktop: needs X11/GL dev packages
     if command -v dnf &>/dev/null; then
@@ -48,10 +57,10 @@ if [[ "$(uname)" == "Linux" ]]; then
 fi
 
 # Clone and build raylib C library
-RAYLIB_COMMIT="aa6ade09ac4bfb2847a356535f2d9f87e49ab089"
+RAYLIB_COMMIT="d9d7cc1353ec0f73c97e84ddf0973983d1ee25e2"
 
 if [ ! -d "raylib-src" ]; then
-  git clone -b master --no-tags https://github.com/commaai/raylib.git raylib-src
+  git clone -b platform-offscreen --no-tags https://github.com/commaai/raylib.git raylib-src
 fi
 
 cd raylib-src
@@ -71,6 +80,29 @@ mkdir -p "$INSTALL_DIR"/{lib,include}
 cp raylib-src/src/libraylib.a "$INSTALL_DIR/lib/"
 cp raylib-src/src/raylib.h raylib-src/src/raymath.h raylib-src/src/rlgl.h "$INSTALL_DIR/include/"
 
+# On x86_64 Linux, also build the offscreen variant for CI headless rendering
+if [[ "$(uname)" == "Linux" && "$(uname -m)" == "x86_64" && "$RAYLIB_PLATFORM" != "PLATFORM_OFFSCREEN" ]]; then
+  echo "Building offscreen variant..."
+  cd raylib-src/src
+  make clean
+  make -j"$NJOBS" PLATFORM=PLATFORM_OFFSCREEN
+  cp libraylib.a "$INSTALL_DIR/lib/libraylib_offscreen.a"
+  cd "$DIR"
+
+  # Bundle GLVND dispatchers so offscreen rendering works without extra system packages
+  MESA_DIR="$INSTALL_DIR/lib/mesa"
+  mkdir -p "$MESA_DIR"
+  for lib in libEGL.so.1 libOpenGL.so.0 libGLdispatch.so.0; do
+    src="$(ldconfig -p 2>/dev/null | grep "$lib" | grep 'x86-64' | awk '{print $NF}' | head -1)"
+    if [ -n "$src" ] && [ -f "$src" ]; then
+      cp -L "$src" "$MESA_DIR/"
+      # Create unversioned symlink for the linker
+      base="${lib%%.so.*}"
+      ln -sf "$lib" "$MESA_DIR/${base}.so"
+    fi
+  done
+fi
+
 # Download raygui header
 RAYGUI_COMMIT="76b36b597edb70ffaf96f046076adc20d67e7827"
 curl -fsSLo "$INSTALL_DIR/include/raygui.h" \