feat: iOS simulator (arm64) support

.github/workflows/postsubmit.yml

@@ -31,6 +31,8 @@ jobs:
         with:
           fetch-depth: 0
       - uses: ./.github/actions/mac-prereq
+      - name: Select Xcode 16.2
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Run build script
         run: |
           cd build/ios && printf "y" | ./build.sh continuous

.github/workflows/presubmit.yml

@@ -184,6 +184,8 @@ jobs:
         with:
           fetch-depth: 0
       - uses: ./.github/actions/mac-prereq
+      - name: Select Xcode 16.2
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Run build script
         run: |
           cd build/ios && printf "y" | ./build.sh presubmit

.github/workflows/release.yml

@@ -286,6 +286,8 @@ jobs:
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
       - uses: ./.github/actions/mac-prereq
+      - name: Select Xcode 16.2
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Run build script
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}

CMakeLists.txt

@@ -732,6 +732,9 @@ string(TOLOWER "${DIST_ARCH}" DIST_ARCH)
 string(REPLACE "amd64" "x86_64" DIST_ARCH "${DIST_ARCH}")
 if (NOT DIST_DIR)
     set(DIST_DIR "${DIST_ARCH}")
+    if (PLATFORM_NAME)
+        set(DIST_DIR "${DIST_DIR}-${PLATFORM_NAME}")
+    endif()
 endif()
 
 # ==================================================================================================

NEW_RELEASE_NOTES.md

@@ -7,4 +7,5 @@ appropriate header in [RELEASE_NOTES.md](./RELEASE_NOTES.md).
 
 ## Release notes for next branch cut
 
+- iOS: add Apple silicon (`arm64`) iOS Simulator support. The sample Xcode projects now require Xcode 16+ (CI is pinned to Xcode 16.2).
 - WEBGL_PTHREADS renamed to WASM_PTHREADS in CMakeLists.txt

build.sh

@@ -53,8 +53,8 @@ function print_help {
     echo "    -e"
     echo "        Enable EGL on Linux support for desktop builds."
     echo "    -l"
-    echo "        Build arm64/x86_64 universal libraries."
-    echo "        For iOS, this builds universal binaries for devices and the simulator (implies -s)."
+    echo "        Build universal libraries/frameworks."
+    echo "        For iOS, this builds XCFrameworks for devices and the simulator (implies -s)."
     echo "        For macOS, this builds universal binaries for both Apple silicon and Intel-based Macs."
     echo "    -k sample1,sample2,..."
     echo "        When building for Android, also build select sample APKs."
@@ -685,9 +685,9 @@ function build_ios_target {
     local platform=$3
 
     echo "Building iOS ${lc_target} (${arch}) for ${platform}..."
-    mkdir -p "out/cmake-ios-${lc_target}-${arch}"
+    mkdir -p "out/cmake-ios-${lc_target}-${arch}-${platform}"
 
-    pushd "out/cmake-ios-${lc_target}-${arch}" > /dev/null
+    pushd "out/cmake-ios-${lc_target}-${arch}-${platform}" > /dev/null
 
     if [[ ! -d "CMakeFiles" ]] || [[ "${ISSUE_CMAKE_ALWAYS}" == "true" ]]; then
         cmake \
@@ -746,38 +746,79 @@ function build_ios {
     # only arm64 devices support OpenGL 3.0 / Metal
 
     if [[ "${ISSUE_DEBUG_BUILD}" == "true" ]]; then
+        local out_dir="out/ios-debug/filament"
+        local lib_dir="${out_dir}/lib"
+
         build_ios_target "Debug" "arm64" "iphoneos"
+
         if [[ "${IOS_BUILD_SIMULATOR}" == "true" ]]; then
+            build_ios_target "Debug" "arm64" "iphonesimulator"
             build_ios_target "Debug" "x86_64" "iphonesimulator"
+
+            # Create a universal library for the simulator
+            build/ios/create-universal-libs.sh \
+                -o "${lib_dir}/universal" \
+                "${lib_dir}/arm64-iphonesimulator" \
+                "${lib_dir}/x86_64-iphonesimulator"
         fi
 
-        if [[ "${BUILD_UNIVERSAL_LIBRARIES}" == "true" ]]; then
-            build/ios/create-universal-libs.sh \
-                -o out/ios-debug/filament/lib/universal \
-                out/ios-debug/filament/lib/arm64 \
-                out/ios-debug/filament/lib/x86_64
-            rm -rf out/ios-debug/filament/lib/arm64
-            rm -rf out/ios-debug/filament/lib/x86_64
+        # Always create XCFrameworks
+        local xcframework_paths=("${lib_dir}/arm64-iphoneos")
+        if [[ -d "${lib_dir}/universal" ]]; then
+            xcframework_paths+=("${lib_dir}/universal")
+        elif [[ -d "${lib_dir}/arm64-iphonesimulator" ]]; then
+            # If we built only one simulator arch but not both
+            xcframework_paths+=("${lib_dir}/arm64-iphonesimulator")
+        elif [[ -d "${lib_dir}/x86_64-iphonesimulator" ]]; then
+            xcframework_paths+=("${lib_dir}/x86_64-iphonesimulator")
         fi
 
+        build/ios/create-xc-frameworks.sh -o "${lib_dir}" "${xcframework_paths[@]}"
+
+        rm -rf \
+            "${lib_dir}/arm64-iphoneos" \
+            "${lib_dir}/arm64-iphonesimulator" \
+            "${lib_dir}/x86_64-iphonesimulator" \
+            "${lib_dir}/universal"
+
         archive_ios "Debug"
     fi
 
     if [[ "${ISSUE_RELEASE_BUILD}" == "true" ]]; then
+        local out_dir="out/ios-release/filament"
+        local lib_dir="${out_dir}/lib"
+
         build_ios_target "Release" "arm64" "iphoneos"
+
         if [[ "${IOS_BUILD_SIMULATOR}" == "true" ]]; then
+            build_ios_target "Release" "arm64" "iphonesimulator"
             build_ios_target "Release" "x86_64" "iphonesimulator"
+
+            # Create a universal library for the simulator
+            build/ios/create-universal-libs.sh \
+                -o "${lib_dir}/universal" \
+                "${lib_dir}/arm64-iphonesimulator" \
+                "${lib_dir}/x86_64-iphonesimulator"
         fi
 
-        if [[ "${BUILD_UNIVERSAL_LIBRARIES}" == "true" ]]; then
-            build/ios/create-universal-libs.sh \
-                -o out/ios-release/filament/lib/universal \
-                out/ios-release/filament/lib/arm64 \
-                out/ios-release/filament/lib/x86_64
-            rm -rf out/ios-release/filament/lib/arm64
-            rm -rf out/ios-release/filament/lib/x86_64
+        # Always create XCFrameworks
+        local xcframework_paths=("${lib_dir}/arm64-iphoneos")
+        if [[ -d "${lib_dir}/universal" ]]; then
+            xcframework_paths+=("${lib_dir}/universal")
+        elif [[ -d "${lib_dir}/arm64-iphonesimulator" ]]; then
+            xcframework_paths+=("${lib_dir}/arm64-iphonesimulator")
+        elif [[ -d "${lib_dir}/x86_64-iphonesimulator" ]]; then
+            xcframework_paths+=("${lib_dir}/x86_64-iphonesimulator")
         fi
 
+        build/ios/create-xc-frameworks.sh -o "${lib_dir}" "${xcframework_paths[@]}"
+
+        rm -rf \
+            "${lib_dir}/arm64-iphoneos" \
+            "${lib_dir}/arm64-iphonesimulator" \
+            "${lib_dir}/x86_64-iphonesimulator" \
+            "${lib_dir}/universal"
+
         archive_ios "Release"
     fi
 }

build/ios/create-xc-frameworks.sh

@@ -0,0 +1,87 @@
+#!/usr/bin/env bash
+
+set -e
+
+function print_help {
+    local SELF_NAME
+    SELF_NAME=$(basename "$0")
+    echo "$SELF_NAME. Combine multiple platform-specific libraries into XCFramework bundles."
+    echo ""
+    echo "Usage:"
+    echo "    $SELF_NAME [options] <path>..."
+    echo ""
+    echo "Options:"
+    echo "    -h"
+    echo "       Print this help message."
+    echo "    -o"
+    echo "       Output directory to store the XCFrameworks."
+    echo ""
+    echo "Example:"
+    echo "    $SELF_NAME -o xcframeworks/ iphoneos/ iphonesimulator/"
+    echo ""
+}
+
+OUTPUT_DIR=""
+while getopts "ho:" opt; do
+    case ${opt} in
+        h)
+            print_help
+            exit 1
+            ;;
+        o)
+            OUTPUT_DIR="${OPTARG}"
+            ;;
+        *)
+            print_help
+            exit 1
+            ;;
+    esac
+done
+
+shift $((OPTIND - 1))
+
+PATHS=("$@")
+
+if [[ ! "${PATHS[*]}" ]]; then
+    echo "One or more paths required."
+    print_help
+    exit 1
+fi
+
+if [[ ! "${OUTPUT_DIR}" ]]; then
+    echo "Output directory required."
+    print_help
+    exit 1
+fi
+
+mkdir -p "${OUTPUT_DIR}"
+
+# Use the first path as the leader to find all .a files
+LEADER_PATH="${PATHS[0]}"
+
+for FILE in "${LEADER_PATH}"/*.a; do
+    [ -f "${FILE}" ] || continue
+
+    LIBRARY_NAME="${FILE##*/}"
+    FRAMEWORK_NAME="${LIBRARY_NAME%.a}.xcframework"
+
+    echo "Creating XCFramework for: ${LIBRARY_NAME}"
+
+    CMD="xcodebuild -create-xcframework"
+
+    for PLATFORM_PATH in "${PATHS[@]}"; do
+        LIB_PATH="${PLATFORM_PATH}/${LIBRARY_NAME}"
+        if [[ -f "${LIB_PATH}" ]]; then
+            CMD="${CMD} -library ${LIB_PATH}"
+        else
+            echo "Warning: ${LIB_PATH} does not exist, skipping this platform for ${LIBRARY_NAME}"
+        fi
+    done
+
+    CMD="${CMD} -output ${OUTPUT_DIR}/${FRAMEWORK_NAME}"
+
+    # Remove existing framework if it exists
+    rm -rf "${OUTPUT_DIR}/${FRAMEWORK_NAME}"
+
+    eval "${CMD}"
+done

filament/backend/src/metal/MetalDriver.mm

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include <TargetConditionals.h>
 #include "backend/PresentCallable.h"
 #include "private/backend/CommandStream.h"
 #include "CommandStreamDispatcher.h"
@@ -160,9 +161,11 @@
     }
 
     mContext->supportsDepthClamp = false;
+#if !TARGET_OS_SIMULATOR
     if (@available(macOS 10.11, iOS 11.0, *)) {
         mContext->supportsDepthClamp = true;
     }
+#endif
 
     // In order to support resolve store action on depth attachment, the GPU needs to support it.
     // Note that support for depth resolve implies support for stencil resolve using .sample0 resolve filter.