shaderfix

docs/shaderfx.md

@@ -220,6 +220,54 @@ output directory; nothing packages it next to a shipped game yet.
 and `ShaderFX.bridgeError()` says why not. Activating an already-converted
 preset never needs any of this.
 
+**Statically linked bridges.** On iOS there is no loadable library at all:
+the bridge is linked straight into the app binary, so its symbols live in the
+main image and are reachable only through `ffi.C`. The candidate list is empty
+on iOS and, on every platform, a failed candidate walk falls back to probing
+`ffi.C` for `librashader_translate_preset` after the `ffi.cdef`. If the symbol
+is there, `ffi.C` becomes the library handle and `ShaderFX.translate` uses it
+unchanged. If it is not, `ShaderFX.bridgeError()` reports that `ffi.C` was
+probed as well, followed by the file paths that were tried (omitted on iOS,
+where none are).
+
+**Android ships the bridge inside the APK.** `scripts/build_android.sh`
+stages `liblibrashader_bridge.so` into
+`mobile/android/app/src/main/jniLibs/<abi>/` for the two ABIs the APK ships,
+arm64-v8a and armeabi-v7a, so `ffi.load("liblibrashader_bridge.so")` finds it
+by bare name in the app's native library directory. The build cross-compiles
+the crate with `cargo ndk` against the same NDK the gradle project uses
+(25.2.9519653), which needs `cargo install cargo-ndk` and
+`rustup target add aarch64-linux-android armv7-linux-androideabi`; the script
+names the exact command for any target that is missing. Set
+`SHADERFX_BRIDGE_ANDROID_DIR` to a directory holding
+`<abi>/liblibrashader_bridge.so` to bundle prebuilt libraries instead. As on
+desktop, the bridge is only needed to CONVERT a preset: a build without it
+still runs presets converted elsewhere, and the packager warns and continues
+rather than failing.
+
+**iOS links the bridge instead of loading it.** An iOS app cannot `dlopen` a
+dylib shipped beside its binary, so `tools/shaderfx-bridge` also builds as a
+`staticlib` and `scripts/build_ios.sh` links it into the app executable
+(`bundle_shader_bridge_ios`, mirroring `bundle_shader_bridge` in
+`scripts/build.sh`). `SHADERFX_BRIDGE_IOS` points at a prebuilt archive;
+otherwise cargo builds `aarch64-apple-ios` for device builds and every
+installed simulator target (`aarch64-apple-ios-sim`, `x86_64-apple-ios`) for
+the Simulator, with `IPHONEOS_DEPLOYMENT_TARGET=15.0`, and `ARCHS` is pinned to
+what got built. The archive is never linked directly: LÖVE 12 carries its own
+glslang for shader validation and the crate drags in a second, incompatible
+one, and linking both crashed inside `Shader::validateInternal` at startup.
+Each slice is therefore prelinked with `ld -r -all_load
+-exported_symbols_list` so only `_librashader_translate_preset` and
+`_librashader_free_string` stay external and every other symbol (glslang,
+spirv-cross, Rust std) becomes private to the object, then `rust-objcopy`
+drops the `__LLVM` bitcode sections rustup's prebuilt std carries, since
+Apple's `nm` cannot read them. `OTHER_LDFLAGS` adds `-Wl,-u` on both entry
+points to keep them past dead-stripping and `-lc++` for the C++ the crate
+needs; no Objective-C framework is involved. A build that linked the object
+fails if `nm` cannot find `_librashader_translate_preset` in the finished
+binary; a build that could not produce one only warns and lands where the
+desktop packages without cargo land: converted presets run, CONVERT does not.
+
 ### Fixup
 
 `ShaderFixup.lua` mechanically rewrites the emitted GLSL into something LOVE
@@ -656,7 +704,8 @@ None of these are theoretical.
   `bundle_shader_bridge`, building it with cargo when a prebuilt one is not
   supplied through `SHADERFX_BRIDGE`. A build host without cargo produces a
   package that can run converted presets but cannot CONVERT new ones, and says
-  so rather than failing. Android ships the `.so` via `jniLibs`.
+  so rather than failing. `scripts/build_android.sh` and `scripts/build_ios.sh`
+  follow the same rule with `cargo ndk` and the iOS static archive.
 - **The buildbot shortlist is a temporary trim.** `KEPT_PRESETS` reflects one
   manual pass over `handheld/` and is expected to change, most likely to shrink.
 - **Tilt direction is unverified.** Which way forward and back rocking moves the

mobile/ANDROID.md

@@ -100,6 +100,11 @@ love-android 11.5a expects:
 Set `ANDROID_SDK_ROOT` (or `ANDROID_HOME`), or let the script write
 `local.properties` when it finds `~/Library/Android/sdk`.
 
+**ShaderFX bridge**: `scripts/build_android.sh` bundles
+`liblibrashader_bridge.so` for arm64-v8a and armeabi-v7a via `cargo ndk` (or
+from `SHADERFX_BRIDGE_ANDROID_DIR`), and warns and continues when neither is
+available; see `docs/shaderfx.md`.
+
 Gradle flavor used: **`embedNoRecord`** (game fused into the APK, no microphone).
 Build task: `assembleEmbedNoRecordDebug`.
 

mobile/ios/README.md

@@ -52,6 +52,7 @@ The script verifies the final app before packaging it:
 
 - the public Documents plist settings are present
 - the native picker bridge is present
+- the SHADER FX librashader bridge is linked into the app binary, when this build produced one
 - `game.love` exists and is non-empty
 
 If the payload is missing, the build fails instead of producing a blank app.

scripts/build_android.sh

@@ -461,6 +461,115 @@ pack_game_love() {
   fi
 }
 
+# --------------------------------------------------------------- ShaderFX bridge
+SHADER_BRIDGE_LIB="liblibrashader_bridge.so"
+SHADER_BRIDGE_ABIS="arm64-v8a armeabi-v7a"
+
+shader_bridge_rust_target() {
+  case "$1" in
+    arm64-v8a)   printf 'aarch64-linux-android' ;;
+    armeabi-v7a) printf 'armv7-linux-androideabi' ;;
+    x86_64)      printf 'x86_64-linux-android' ;;
+    x86)         printf 'i686-linux-android' ;;
+    *)           printf '' ;;
+  esac
+}
+
+shader_bridge_staged_count() {
+  local jni="$1" abi count=0
+  for abi in $SHADER_BRIDGE_ABIS; do
+    [ -f "$jni/$abi/$SHADER_BRIDGE_LIB" ] && count=$((count + 1))
+  done
+  printf '%s' "$count"
+}
+
+bundle_shader_bridge_android() {
+  local jni="$ANDROID_DIR/app/src/main/jniLibs"
+  local crate="$ROOT/tools/shaderfx-bridge"
+  local abi target
+
+  for abi in $SHADER_BRIDGE_ABIS; do
+    rm -f "$jni/$abi/$SHADER_BRIDGE_LIB"
+  done
+
+  local prebuilt="${SHADERFX_BRIDGE_ANDROID_DIR:-}"
+  if [ -n "$prebuilt" ]; then
+    for abi in $SHADER_BRIDGE_ABIS; do
+      if [ -f "$prebuilt/$abi/$SHADER_BRIDGE_LIB" ]; then
+        mkdir -p "$jni/$abi"
+        cp "$prebuilt/$abi/$SHADER_BRIDGE_LIB" "$jni/$abi/$SHADER_BRIDGE_LIB"
+      else
+        warn "SHADERFX_BRIDGE_ANDROID_DIR has no $abi/$SHADER_BRIDGE_LIB"
+      fi
+    done
+    if [ "$(shader_bridge_staged_count "$jni")" -gt 0 ]; then
+      say "bundled $SHADER_BRIDGE_LIB for SHADER FX preset conversion (prebuilt)"
+      return
+    fi
+  fi
+
+  if [ ! -f "$crate/Cargo.toml" ]; then
+    warn "$SHADER_BRIDGE_LIB not found: this build can run converted presets but not CONVERT new ones (tools/shaderfx-bridge is missing)"
+    return
+  fi
+
+  if ! command -v cargo >/dev/null 2>&1 || ! cargo ndk --version >/dev/null 2>&1; then
+    warn "$SHADER_BRIDGE_LIB not found: this build can run converted presets but not CONVERT new ones (set SHADERFX_BRIDGE_ANDROID_DIR or run 'cargo install cargo-ndk')"
+    return
+  fi
+
+  local ndk="${ANDROID_NDK_HOME:-}"
+  if [ -z "$ndk" ] || [ ! -d "$ndk" ]; then
+    ndk="${ANDROID_SDK_ROOT:-${ANDROID_HOME:-$HOME/Library/Android/sdk}}/ndk/$NDK_VERSION"
+  fi
+  if [ ! -d "$ndk" ]; then
+    warn "$SHADER_BRIDGE_LIB not built: NDK $NDK_VERSION not found (set ANDROID_NDK_HOME)"
+    return
+  fi
+
+  local installed missing="" buildable=""
+  installed="$(rustup target list --installed 2>/dev/null || true)"
+  for abi in $SHADER_BRIDGE_ABIS; do
+    target="$(shader_bridge_rust_target "$abi")"
+    if grep -qx "$target" <<< "$installed"; then
+      buildable="$buildable $abi"
+    else
+      missing="$missing $target"
+    fi
+  done
+  if [ -n "$missing" ]; then
+    warn "$SHADER_BRIDGE_LIB: skipping$missing. Run: rustup target add$missing"
+  fi
+  if [ -z "$buildable" ]; then
+    warn "$SHADER_BRIDGE_LIB not built: this build can run converted presets but not CONVERT new ones (no Android Rust targets installed)"
+    return
+  fi
+
+  local args=()
+  for abi in $buildable; do
+    args+=(-t "$abi")
+  done
+
+  say "building the ShaderFX bridge with cargo-ndk (${buildable# })"
+  mkdir -p "$jni"
+  if ! (
+    cd "$crate"
+    export ANDROID_NDK_HOME="$ndk"
+    export ANDROID_NDK_ROOT="$ndk"
+    export CARGO_PROFILE_RELEASE_STRIP="symbols"
+    cargo ndk "${args[@]}" -o "$jni" build --release
+  ); then
+    warn "$SHADER_BRIDGE_LIB failed to cross-compile: this build can run converted presets but not CONVERT new ones"
+    return
+  fi
+
+  if [ "$(shader_bridge_staged_count "$jni")" -gt 0 ]; then
+    say "bundled $SHADER_BRIDGE_LIB for SHADER FX preset conversion"
+  else
+    warn "$SHADER_BRIDGE_LIB not found after cargo-ndk: this build can run converted presets but not CONVERT new ones"
+  fi
+}
+
 # --------------------------------------------------------------- SDK check
 require_android_sdk() {
   local sdk="${ANDROID_SDK_ROOT:-${ANDROID_HOME:-}}"
@@ -575,5 +684,6 @@ if $PACKAGE_ONLY; then
 fi
 
 require_android_sdk
+bundle_shader_bridge_android
 run_gradle
 say "done"

scripts/build_ios.sh

@@ -615,6 +615,138 @@ verify_game_payload() {
   say "game.love present ($(du -h "$app/game.love" | cut -f1))"
 }
 
+SHADER_BRIDGE_LIB=""
+SHADER_BRIDGE_NAME="liblibrashader_bridge.a"
+SHADER_BRIDGE_OBJ="librashader_bridge.o"
+
+SHADER_BRIDGE_ARCHS=""
+
+rust_targets_for_sdk() {
+  if [ "$1" = "iphoneos" ]; then
+    printf 'aarch64-apple-ios'
+  else
+    printf 'aarch64-apple-ios-sim x86_64-apple-ios'
+  fi
+}
+
+build_shader_bridge_slice() {
+  local rust_target="$1"
+  local crate="$ROOT/tools/shaderfx-bridge"
+  local built="$crate/target/$rust_target/release/$SHADER_BRIDGE_NAME"
+  if [ -f "$built" ]; then
+    printf '%s' "$built"
+    return 0
+  fi
+  if command -v cargo >/dev/null 2>&1 \
+      && rustup target list --installed 2>/dev/null \
+         | grep -x "$rust_target" >/dev/null; then
+    say "building the ShaderFX bridge with cargo ($rust_target)" >&2
+    if (cd "$crate" && IPHONEOS_DEPLOYMENT_TARGET=15.0 \
+        cargo build --release --target "$rust_target" >/dev/null 2>&1); then
+      printf '%s' "$built"
+      return 0
+    fi
+  fi
+  return 1
+}
+
+prelink_shader_bridge_slice() {
+  local archive="$1" sdk="$2" out="$3"
+  local arch platform sdk_version syms objcopy tmp
+  arch="$(lipo -archs "$archive" 2>/dev/null | awk '{print $1}')"
+  [ -n "$arch" ] || return 1
+  if [ "$sdk" = "iphoneos" ]; then platform="ios"; else platform="ios-simulator"; fi
+  sdk_version="$(xcrun --sdk "$sdk" --show-sdk-version 2>/dev/null)"
+  [ -n "$sdk_version" ] || return 1
+  syms="$LIBS_DIR/librashader_bridge.exports"
+  printf '_librashader_translate_preset\n_librashader_free_string\n' > "$syms"
+  tmp="$out.tmp"
+  xcrun ld -r -arch "$arch" -platform_version "$platform" 15.0 "$sdk_version" \
+    -all_load -exported_symbols_list "$syms" -o "$tmp" "$archive" || return 1
+  objcopy="$(ls "$(rustc --print sysroot 2>/dev/null)"/lib/rustlib/*/bin/rust-objcopy 2>/dev/null | head -1)"
+  if [ -n "$objcopy" ] && "$objcopy" --remove-section __LLVM,__bitcode \
+       --remove-section __LLVM,__cmdline "$tmp" "$out" 2>/dev/null; then
+    rm -f "$tmp"
+  else
+    mv "$tmp" "$out"
+  fi
+}
+
+bundle_shader_bridge_ios() {
+  local rust_targets="$1" sdk="$2"
+  local src="${SHADERFX_BRIDGE_IOS:-}"
+  local slices=() objs=() target slice obj i
+  SHADER_BRIDGE_LIB=""
+  SHADER_BRIDGE_ARCHS=""
+  rm -f "$LIBS_DIR/$SHADER_BRIDGE_NAME" "$LIBS_DIR/$SHADER_BRIDGE_OBJ" "$LIBS_DIR"/librashader_bridge.*.o
+  if [ -n "$src" ]; then
+    if [ -f "$src" ]; then
+      slices+=("$src")
+    else
+      warn "SHADERFX_BRIDGE_IOS=$src does not exist"
+    fi
+  else
+    for target in $rust_targets; do
+      if slice="$(build_shader_bridge_slice "$target")"; then
+        slices+=("$slice")
+      fi
+    done
+  fi
+  if [ "${#slices[@]}" -gt 0 ]; then
+    mkdir -p "$LIBS_DIR"
+    i=0
+    for slice in "${slices[@]}"; do
+      i=$((i + 1))
+      obj="$LIBS_DIR/librashader_bridge.$i.o"
+      if prelink_shader_bridge_slice "$slice" "$sdk" "$obj"; then
+        objs+=("$obj")
+      else
+        warn "could not prelink $(basename "$slice") for $sdk"
+      fi
+    done
+  fi
+  if [ "${#objs[@]}" -eq 1 ]; then
+    mv "${objs[0]}" "$LIBS_DIR/$SHADER_BRIDGE_OBJ"
+  elif [ "${#objs[@]}" -gt 1 ]; then
+    lipo -create "${objs[@]}" -output "$LIBS_DIR/$SHADER_BRIDGE_OBJ"
+    rm -f "${objs[@]}"
+  fi
+  if [ -f "$LIBS_DIR/$SHADER_BRIDGE_OBJ" ]; then
+    SHADER_BRIDGE_LIB="$LIBS_DIR/$SHADER_BRIDGE_OBJ"
+    SHADER_BRIDGE_ARCHS="$(lipo -archs "$SHADER_BRIDGE_LIB" 2>/dev/null || true)"
+    say "linking $SHADER_BRIDGE_OBJ for SHADER FX preset conversion (${SHADER_BRIDGE_ARCHS:-unknown arch})"
+  else
+    warn "$SHADER_BRIDGE_NAME not found: this build can run converted presets but not CONVERT new ones (set SHADERFX_BRIDGE_IOS, or install cargo plus one of: rustup target add $rust_targets)"
+  fi
+}
+
+verify_shader_bridge() {
+  local app="$1"
+  local exe bin
+  if [ -z "$SHADER_BRIDGE_LIB" ]; then
+    warn "no SHADER FX bridge in this build: CONVERT stays unavailable, converted presets still run"
+    return 0
+  fi
+  exe="$(/usr/libexec/PlistBuddy -c 'Print :CFBundleExecutable' \
+         "$app/Info.plist" 2>/dev/null || true)"
+  bin="$app/${exe:-love}"
+  [ -f "$bin" ] || bin="$app/love"
+  if [ ! -f "$bin" ]; then
+    warn "no executable inside $(basename "$app"); skipping SHADER FX bridge check"
+    return 0
+  fi
+  if nm "$bin" 2>/dev/null | grep -E ' _librashader_translate_preset$' >/dev/null \
+     || xcrun dyld_info -exports "$bin" 2>/dev/null \
+        | grep -E ' _librashader_translate_preset$' >/dev/null; then
+    say "SHADER FX bridge present (librashader_translate_preset)"
+    return 0
+  fi
+  fail "built app does not carry the SHADER FX bridge symbols.
+  $SHADER_BRIDGE_OBJ was linked but librashader_translate_preset is absent,
+  so SHADER FX CONVERT would fail at runtime.
+  Rebuild after: rm -rf tools/shaderfx-bridge/target"
+}
+
 run_xcodebuild() {
   local config sdk destination
   if $RELEASE; then
@@ -633,6 +765,8 @@ run_xcodebuild() {
 
   mkdir -p "$BUILD_DIR"
 
+  bundle_shader_bridge_ios "$(rust_targets_for_sdk "$sdk")" "$sdk"
+
   # Prefer -target + SYMROOT over -derivedDataPath: modern Xcode requires
   # -scheme whenever -derivedDataPath is set, and love-ios ships no shared schemes.
   # Always stamp both: the overlay plist expands $(MARKETING_VERSION) /
@@ -661,6 +795,13 @@ run_xcodebuild() {
     ONLY_ACTIVE_ARCH=NO
     DISABLE_MANUAL_TARGET_ORDER_BUILD_WARNING=YES
   )
+  if [ -n "$SHADER_BRIDGE_LIB" ]; then
+    args+=(OTHER_LDFLAGS="-Wl,-u,_librashader_translate_preset -Wl,-u,_librashader_free_string \"$SHADER_BRIDGE_LIB\" -lc++")
+    if [ -n "$SHADER_BRIDGE_ARCHS" ]; then
+      args+=(ARCHS="$SHADER_BRIDGE_ARCHS")
+    fi
+  fi
+
   if ! $DEVICE; then
     # Simulator: ad-hoc signing (no certificate needed). A plain unsigned
     # build would drop the entitlements file, and HealthKit refuses to run
@@ -723,11 +864,14 @@ run_xcodebuild() {
 
   local products="$BUILD_DIR/Build/Products/${config}-${sdk}"
   local app=""
-  local candidate
+  local candidate newest=0 mtime
   for candidate in "$products/$PRODUCT_NAME.app" "$products/$APP_NAME.app" "$products/love.app"; do
     if [ -d "$candidate" ]; then
+      mtime="$(stat -f %m "$candidate" 2>/dev/null || echo 0)"
+      if [ "$mtime" -gt "$newest" ]; then
+        newest="$mtime"
         app="$candidate"
-      break
+      fi
     fi
   done
   if [ -z "$app" ]; then
@@ -736,6 +880,7 @@ run_xcodebuild() {
     return 0
   fi
   if [ "$app" != "$products/$APP_NAME.app" ]; then
+    rm -rf "$products/$APP_NAME.app"
     mv "$app" "$products/$APP_NAME.app"
     app="$products/$APP_NAME.app"
   fi
@@ -754,6 +899,7 @@ run_xcodebuild() {
 
   verify_game_payload "$app"
   verify_native_bridge "$app"
+  verify_shader_bridge "$app"
 
   local dist_dir="$DIST/${config}-${sdk}"
   rm -rf "$dist_dir"

src/core/Sensors.lua

@@ -76,7 +76,14 @@ local function sdlFfi()
     ]])
     if sdlCdefOk then
       local okLoad, lib = pcall(ffi.load, "SDL2")
-      sdlLib = okLoad and lib or ffi.C
+      lib = okLoad and lib or ffi.C
+      local okSyms = pcall(function()
+        return lib.SDL_InitSubSystem, lib.SDL_NumSensors, lib.SDL_SensorGetDeviceType,
+          lib.SDL_SensorOpen, lib.SDL_SensorUpdate, lib.SDL_SensorGetData,
+          lib.SDL_GL_GetCurrentWindow, lib.SDL_GetWindowDisplayIndex,
+          lib.SDL_GetDisplayOrientation
+      end)
+      sdlLib = okSyms and lib or false
     end
   end
   if not sdlCdefOk or not sdlLib then return nil end

src/import/LauncherView.lua

@@ -984,6 +984,17 @@ local function modScopeChipsWidth(options, gap, m)
   return need
 end
 
+local function profileState(imp)
+  if imp._profileCache == nil then
+    local LauncherMods = require("src.mods.LauncherMods")
+    local SaveData = require("src.core.SaveData")
+    local options = SaveData.loadOptions()
+    local list, cur = LauncherMods.getProfiles(options)
+    imp._profileCache = { options = options, list = list, active = cur }
+  end
+  return imp._profileCache
+end
+
 local function buildModScopeRow(imp, x, y, w, m)
   local LauncherMods = require("src.mods.LauncherMods")
   local h = math.max(Kit.tapMin(), math.floor(26 * m.s))
@@ -994,7 +1005,7 @@ local function buildModScopeRow(imp, x, y, w, m)
   local options = modScopeOptions(imp)
 
   -- Dedicated Profile control section (cycle button + gear icon button) on right side of Scope Bar
-  local _, activeProf = LauncherMods.getProfiles()
+  local activeProf = profileState(imp).active
   local isCompact = (w < math.floor(500 * m.s))
   local nameText = tostring(activeProf or "Default")
   local profLabel = isCompact and nameText or Strings("Profile: %s", nameText)
@@ -3698,9 +3709,8 @@ local function buildSingleProfileActionsModal(imp, m)
   if not pName then imp._singleProfileActions = nil return end
 
   local LauncherMods = require("src.mods.LauncherMods")
-  local SaveData = require("src.core.SaveData")
+  local prof = profileState(imp)
-  local options = SaveData.loadOptions()
+  local options, profiles = prof.options, prof.list
-  local profiles, active = LauncherMods.getProfiles(options)
 
   local pad = math.floor(18 * m.s)
   local w = math.min(math.floor(380 * m.s), m.w - 2 * m.pad)
@@ -3715,6 +3725,7 @@ local function buildSingleProfileActionsModal(imp, m)
       action = function()
         LauncherMods.duplicateProfile(pName, options)
         imp._singleProfileActions = nil
+        if imp._refreshMods then imp:_refreshMods() end
       end
     },
     {
@@ -3736,6 +3747,7 @@ local function buildSingleProfileActionsModal(imp, m)
         imp:pressDelete("profile", pName, nil, function()
           LauncherMods.deleteProfile(pName, options)
           imp._singleProfileActions = nil
+          if imp._refreshMods then imp:_refreshMods() end
         end)
       end
     }
@@ -3771,9 +3783,8 @@ end
 -- Modal for Mod Profiles (#593) - interactive profile manager (switch, edit, duplicate, delete)
 local function buildProfilesModal(imp, m)
   local LauncherMods = require("src.mods.LauncherMods")
-  local SaveData = require("src.core.SaveData")
+  local prof = profileState(imp)
-  local options = SaveData.loadOptions()
+  local options, profiles, active = prof.options, prof.list, prof.active
-  local profiles, active = LauncherMods.getProfiles(options)
 
   local pad = math.floor(18 * m.s)
   local w = math.min(math.floor(460 * m.s), m.w - 2 * m.pad)

src/import/RomImporter.lua

@@ -4803,6 +4803,7 @@ function RomImporter:_refreshMods()
   local LauncherMods = require("src.mods.LauncherMods")
   local SaveData = require("src.core.SaveData")
   self._cartPlan = nil
+  self._profileCache = nil
   self.findInstalled = nil
   self.safeMode = SaveData.isSafeMode(SaveData.loadOptions())
   -- Once per session, ahead of the first listing: pull in any mod the player

src/render/ShaderFX.lua

@@ -264,7 +264,9 @@ ShaderFX.BRIDGE_DIR = "tools/shaderfx-bridge"
 local function libNames()
   local osName = (love and love.system and love.system.getOS
     and love.system.getOS()) or ""
-  if osName == "Windows" then
+  if osName == "iOS" then
+    return {}
+  elseif osName == "Windows" then
     return { "librashader_bridge.dll" }
   elseif osName == "OS X" then
     return { "liblibrashader_bridge.dylib", "librashader_bridge.dylib" }
@@ -313,11 +315,13 @@ end
 
 -- Every place the bridge may sit, most specific first.
 local function libCandidates()
+  local names = libNames()
+  if #names == 0 then return {} end
   local out = {}
   local override = os.getenv("LIBRASHADER_BRIDGE_DLL")
   if override and override ~= "" then out[#out + 1] = override end
   local dirs, save = sourceDirs(), saveDir()
-  for _, name in ipairs(libNames()) do
+  for _, name in ipairs(names) do
     for _, dir in ipairs(dirs) do
       out[#out + 1] = dir .. "/" .. name
       out[#out + 1] = dir .. "/" .. ShaderFX.BRIDGE_DIR .. "/target/release/" .. name
@@ -353,7 +357,17 @@ local function ensureLib()
     end
     tried[#tried + 1] = path
   end
-  libError = "librashader bridge not found; looked in " .. table.concat(tried, ", ")
+  local okSym, sym = pcall(function()
+    return ffi.C and ffi.C.librashader_translate_preset
+  end)
+  if okSym and sym ~= nil then
+    lib = ffi.C
+    return lib
+  end
+  libError = "librashader bridge not found; ffi.C has no librashader_translate_preset"
+  if #tried > 0 then
+    libError = libError .. "; looked in " .. table.concat(tried, ", ")
+  end
   return nil, libError
 end
 

tests/engine/shaderfx_ffi_c_fallback.lua

@@ -0,0 +1,85 @@
+package.path = "./?.lua;./?/init.lua;" .. package.path
+
+local T = require("tests.harness")
+
+love = love or require("tests.love_stub")
+
+local NAME = "src.render.ShaderFX"
+
+local function withFfi(fakeFfi, os, fn)
+  local oldModule = package.loaded[NAME]
+  local oldFfi = package.loaded.ffi
+  local oldPreload = package.preload.ffi
+  local oldGetOS = love.system.getOS
+  if os then love.system.getOS = function() return os end end
+  package.loaded[NAME] = nil
+  package.loaded.ffi = nil
+  package.preload.ffi = function() return fakeFfi end
+  local ShaderFX = require(NAME)
+  local can, err = ShaderFX.canConvert(), ShaderFX.bridgeError()
+  if fn then fn(ShaderFX) end
+  package.loaded[NAME] = oldModule
+  package.loaded.ffi = oldFfi
+  package.preload.ffi = oldPreload
+  love.system.getOS = oldGetOS
+  return can, err, ShaderFX
+end
+
+local function baseFfi()
+  return {
+    cdef = function() end,
+    load = function() error("no such library") end,
+    string = function(value) return value end,
+  }
+end
+
+local staticFfi = baseFfi()
+staticFfi.C = {
+  librashader_translate_preset = function() return "{}" end,
+  librashader_free_string = function() end,
+}
+
+local can, err = withFfi(staticFfi)
+T.eq(can, true, "a statically linked bridge is found through ffi.C")
+T.eq(err, nil, "the ffi.C fallback leaves no bridge error behind")
+
+local emptyFfi = baseFfi()
+emptyFfi.C = setmetatable({}, {
+  __index = function() error("undefined symbol") end,
+})
+
+local missing, missingErr = withFfi(emptyFfi)
+T.eq(missing, false, "no library and no ffi.C symbol means no conversion")
+T.check(missingErr and missingErr:find("ffi.C has no librashader_translate_preset", 1, true) ~= nil,
+  "libError says ffi.C was probed too (got " .. tostring(missingErr) .. ")")
+T.check(missingErr and missingErr:find("looked in", 1, true) ~= nil,
+  "libError still lists the paths that were tried")
+
+local iosMissing, iosErr = withFfi(baseFfi(), "iOS")
+T.eq(iosMissing, false, "iOS with no static symbol cannot convert")
+T.check(iosErr and iosErr:find("ffi.C has no librashader_translate_preset", 1, true) ~= nil,
+  "iOS libError names the ffi.C probe")
+T.check(iosErr and iosErr:find("looked in", 1, true) == nil,
+  "iOS lists no file candidates (got " .. tostring(iosErr) .. ")")
+
+local iosCan = withFfi(staticFfi, "iOS")
+T.eq(iosCan, true, "iOS resolves the bridge through ffi.C alone")
+
+local freed = false
+local translateFfi = baseFfi()
+translateFfi.C = {
+  librashader_translate_preset = function(path, es)
+    return ('{"pass_count":1,"passes":[{"name":"%s","es":%d}]}'):format(path, es)
+  end,
+  librashader_free_string = function() freed = true end,
+}
+withFfi(translateFfi, "iOS", function(ShaderFX)
+  local preset, terr = ShaderFX.translate("/presets/a.slangp", true)
+  T.check(preset ~= nil, "translate works with lib == ffi.C (" .. tostring(terr) .. ")")
+  T.eq(preset and preset.passes[1].name, "/presets/a.slangp",
+    "the ffi.C symbol receives the preset path")
+  T.eq(preset and preset.passes[1].es, 1, "the es flag reaches the ffi.C symbol")
+  T.eq(freed, true, "the returned string is freed through ffi.C")
+end)
+
+T.finish("shaderfx ffi.C fallback")

tools/shaderfx-bridge/Cargo.toml

@@ -5,7 +5,7 @@ edition = "2024"
 
 [lib]
 name = "librashader_bridge"
-crate-type = ["cdylib", "rlib"]
+crate-type = ["cdylib", "staticlib", "rlib"]
 
 [dependencies]
 librashader-preprocess = "0.12.0"