libobs: Add Metal renderer for Apple Silicon Macs

.github/workflows/analyze-project.yaml

@@ -57,8 +57,8 @@ jobs:
           : Set Up Environment 🔧
           if (( ${+RUNNER_DEBUG} )) setopt XTRACE
 
-          print '::group::Enable Xcode 16.1'
-          sudo xcode-select --switch /Applications/Xcode_16.1.0.app/Contents/Developer
+          print '::group::Enable Xcode 16.4'
+          sudo xcode-select --switch /Applications/Xcode_16.4.app/Contents/Developer
           print '::endgroup::'
 
           print '::group::Clean Homebrew Environment'

.github/workflows/build-project.yaml

@@ -80,8 +80,8 @@ jobs:
           : Set Up Environment 🔧
           if (( ${+RUNNER_DEBUG} )) setopt XTRACE
 
-          print '::group::Enable Xcode 16.1'
-          sudo xcode-select --switch /Applications/Xcode_16.1.0.app/Contents/Developer
+          print '::group::Enable Xcode 16.4'
+          sudo xcode-select --switch /Applications/Xcode_16.4.app/Contents/Developer
           print '::endgroup::'
 
           print '::group::Clean Homebrew Environment'

.swift-format

@@ -8,5 +8,16 @@
     "maximumBlankLines": 1,
     "respectsExistingLineBreaks": true,
     "lineBreakBeforeControlFlowKeywords": false,
-    "lineBreakBeforeEachArgument": false
+    "lineBreakBeforeEachArgument": false,
+    "lineBreakBeforeEachGenericRequirement": false,
+    "lineBreakBetweenDeclarationAttributes": false,
+    "prioritizeKeepingFunctionOutputTogether": false,
+    "indentConditionalCompilationBlocks": true,
+    "lineBreakAroundMultilineExpressionChainComponents": false,
+    "fileScopedDeclarationPrivacy": {"accessLevel": "private"},
+    "indentSwitchCaseLabels": false,
+    "spacesAroundRangeFormationOperators": false,
+    "noAssignmentInExpressions": { "allowedFunctions" : ["XCTAssertNoThrow"] },
+    "multiElementCollectionTrailingCommas": true,
+    "indentBlankLines": false,
 }

CMakeLists.txt

@@ -25,6 +25,9 @@ if(OS_WINDOWS)
   add_subdirectory(libobs-winrt)
 endif()
 add_subdirectory(libobs-opengl)
+if(OS_MACOS)
+  add_subdirectory(libobs-metal)
+endif()
 add_subdirectory(plugins)
 
 add_subdirectory(test/test-input)

cmake/macos/compilerconfig.cmake

@@ -88,7 +88,7 @@ string(APPEND CMAKE_OBJCXX_FLAGS_RELEASE " -g")
 # * -Wno-non-virtual-dtor
 
 add_compile_definitions(
-  $<$<NOT:$<COMPILE_LANGUAGE:Swift>>:$<$<CONFIG:DEBUG>:DEBUG>>
+  $<$<CONFIG:DEBUG>:DEBUG>
   $<$<NOT:$<COMPILE_LANGUAGE:Swift>>:$<$<CONFIG:DEBUG>:_DEBUG>>
   $<$<NOT:$<COMPILE_LANGUAGE:Swift>>:SIMDE_ENABLE_OPENMP>
 )

frontend/OBSApp.cpp

@@ -291,9 +291,14 @@ bool OBSApp::InitGlobalConfigDefaults()
 
 #if _WIN32
 	config_set_default_string(appConfig, "Video", "Renderer", "Direct3D 11");
+#else
+#if defined(__APPLE__) && defined(__aarch64__)
+	// TODO: Change this value to "Metal" once the renderer has reached production quality
+	config_set_default_string(appConfig, "Video", "Renderer", "OpenGL");
 #else
 	config_set_default_string(appConfig, "Video", "Renderer", "OpenGL");
 #endif
+#endif
 
 #ifdef _WIN32
 	config_set_default_bool(appConfig, "Audio", "DisableAudioDucking", true);
@@ -1077,9 +1082,17 @@ void OBSApp::checkForUncleanShutdown()
 
 const char *OBSApp::GetRenderModule() const
 {
+#if defined(_WIN32)
 	const char *renderer = config_get_string(appConfig, "Video", "Renderer");
 
 	return (astrcmpi(renderer, "Direct3D 11") == 0) ? DL_D3D11 : DL_OPENGL;
+#elif defined(__APPLE__) && defined(__aarch64__)
+	const char *renderer = config_get_string(appConfig, "Video", "Renderer");
+
+	return (astrcmpi(renderer, "Metal (Experimental)") == 0) ? DL_METAL : DL_OPENGL;
+#else
+	return DL_OPENGL;
+#endif
 }
 
 static bool StartupOBS(const char *locale, profiler_name_store_t *store)

frontend/settings/OBSBasicSettings.cpp

@@ -608,11 +608,24 @@ OBSBasicSettings::OBSBasicSettings(QWidget *parent)
 	for (ProcessPriority pri : processPriorities)
 		ui->processPriority->addItem(QTStr(pri.name), pri.val);
 
+#else
+#if defined(__APPLE__) && defined(__aarch64__)
+	delete ui->adapterLabel;
+	delete ui->adapter;
+
+	ui->adapterLabel = nullptr;
+	ui->adapter = nullptr;
 #else
 	delete ui->rendererLabel;
 	delete ui->renderer;
 	delete ui->adapterLabel;
 	delete ui->adapter;
+
+	ui->rendererLabel = nullptr;
+	ui->renderer = nullptr;
+	ui->adapterLabel = nullptr;
+	ui->adapter = nullptr;
+#endif
 	delete ui->processPriorityLabel;
 	delete ui->processPriority;
 	delete ui->enableNewSocketLoop;
@@ -624,10 +637,6 @@ OBSBasicSettings::OBSBasicSettings(QWidget *parent)
 #endif
 	delete ui->disableAudioDucking;
 
-	ui->rendererLabel = nullptr;
-	ui->renderer = nullptr;
-	ui->adapterLabel = nullptr;
-	ui->adapter = nullptr;
 	ui->processPriorityLabel = nullptr;
 	ui->processPriority = nullptr;
 	ui->enableNewSocketLoop = nullptr;
@@ -1384,16 +1393,21 @@ void OBSBasicSettings::LoadGeneralSettings()
 
 void OBSBasicSettings::LoadRendererList()
 {
-#ifdef _WIN32
+#if defined(_WIN32) || (defined(__APPLE__) && defined(__aarch64__))
 	const char *renderer = config_get_string(App()->GetAppConfig(), "Video", "Renderer");
-
+#ifdef _WIN32
 	ui->renderer->addItem(QT_UTF8("Direct3D 11"));
-	if (opt_allow_opengl || strcmp(renderer, "OpenGL") == 0)
+	if (opt_allow_opengl || strcmp(renderer, "OpenGL") == 0) {
 		ui->renderer->addItem(QT_UTF8("OpenGL"));
-
-	int idx = ui->renderer->findText(QT_UTF8(renderer));
-	if (idx == -1)
-		idx = 0;
+	}
+#else
+	ui->renderer->addItem(QT_UTF8("OpenGL"));
+	ui->renderer->addItem(QT_UTF8("Metal (Experimental)"));
+#endif
+	int index = ui->renderer->findText(QT_UTF8(renderer));
+	if (index == -1) {
+		index = 0;
+	}
 
 	// the video adapter selection is not currently implemented, hide for now
 	// to avoid user confusion. was previously protected by
@@ -1403,7 +1417,7 @@ void OBSBasicSettings::LoadRendererList()
 	ui->adapter = nullptr;
 	ui->adapterLabel = nullptr;
 
-	ui->renderer->setCurrentIndex(idx);
+	ui->renderer->setCurrentIndex(index);
 #endif
 }
 
@@ -3130,10 +3144,13 @@ void OBSBasicSettings::SaveAdvancedSettings()
 {
 	QString lastMonitoringDevice = config_get_string(main->Config(), "Audio", "MonitoringDeviceId");
 
-#ifdef _WIN32
-	if (WidgetChanged(ui->renderer))
+#if defined(_WIN32) || (defined(__APPLE__) && defined(__aarch64__))
+	if (WidgetChanged(ui->renderer)) {
 		config_set_string(App()->GetAppConfig(), "Video", "Renderer", QT_TO_UTF8(ui->renderer->currentText()));
+	}
+#endif
 
+#ifdef _WIN32
 	std::string priority = QT_TO_UTF8(ui->processPriority->currentData().toString());
 	config_set_string(App()->GetAppConfig(), "General", "ProcessPriority", priority.c_str());
 	if (main->Active())

libobs-metal/CMakeLists.txt

@@ -0,0 +1,70 @@
+cmake_minimum_required(VERSION 3.28...3.30)
+
+add_library(libobs-metal SHARED)
+add_library(OBS::libobs-metal ALIAS libobs-metal)
+
+target_sources(
+  libobs-metal
+  PRIVATE
+    CVPixelFormat+Extensions.swift
+    MTLCullMode+Extensions.swift
+    MTLOrigin+Extensions.swift
+    MTLPixelFormat+Extensions.swift
+    MTLRegion+Extensions.swift
+    MTLSize+Extensions.swift
+    MTLTexture+Extensions.swift
+    MTLTextureDescriptor+Extensions.swift
+    MTLTextureType+Extensions.swift
+    MTLViewport+Extensions.swift
+    MetalBuffer.swift
+    MetalDevice.swift
+    MetalError.swift
+    MetalRenderState.swift
+    MetalShader+Extensions.swift
+    MetalShader.swift
+    MetalStageBuffer.swift
+    MetalTexture.swift
+    OBSShader.swift
+    OBSSwapChain.swift
+    Sequence+Hashable.swift
+    libobs+Extensions.swift
+    libobs+SignalHandlers.swift
+    libobs-metal-Bridging-Header.h
+    metal-indexbuffer.swift
+    metal-samplerstate.swift
+    metal-shader.swift
+    metal-stagesurf.swift
+    metal-subsystem.swift
+    metal-swapchain.swift
+    metal-texture2d.swift
+    metal-texture3d.swift
+    metal-unimplemented.swift
+    metal-vertexbuffer.swift
+    metal-zstencilbuffer.swift
+)
+
+target_link_libraries(libobs-metal PRIVATE OBS::libobs)
+
+target_enable_feature(libobs "Metal renderer")
+
+set_property(SOURCE OBSMetalRenderer.swift APPEND PROPERTY COMPILE_FLAGS -emit-objc-header)
+
+set_target_properties_obs(
+    libobs-metal
+    PROPERTIES FOLDER core
+               VERSION 0
+               PREFIX ""
+)
+
+set_target_xcode_properties(
+    libobs-metal
+    PROPERTIES SWIFT_VERSION 6.0
+               CLANG_ENABLE_OBJC_ARC YES
+               CLANG_WARN_SUSPICIOUS_IMPLICIT_CONVERSION YES
+               GCC_WARN_SHADOW YES
+               CLANG_ENABLE_MODULES YES
+               CLANG_MODULES_AUTOLINK YES
+               GCC_STRICT_ALIASING YES
+               DEFINES_MODULE YES
+               SWIFT_OBJC_BRIDGING_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/libobs-metal-Bridging-Header.h"
+)

libobs-metal/CVPixelFormat+Extensions.swift

@@ -0,0 +1,51 @@
+/******************************************************************************
+ Copyright (C) 2024 by Patrick Heyer <PatTheMav@users.noreply.github.com>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ ******************************************************************************/
+
+import CoreVideo
+import Metal
+
+extension OSType {
+    /// Conversion of CoreVideo pixel formats into corresponding Metal pixel formats
+    var mtlFormat: MTLPixelFormat? {
+        switch self {
+        case kCVPixelFormatType_OneComponent8:
+            return .r8Unorm
+        case kCVPixelFormatType_OneComponent16Half:
+            return .r16Float
+        case kCVPixelFormatType_OneComponent32Float:
+            return .r32Float
+        case kCVPixelFormatType_TwoComponent8:
+            return .rg8Unorm
+        case kCVPixelFormatType_TwoComponent16Half:
+            return .rg16Float
+        case kCVPixelFormatType_TwoComponent32Float:
+            return .rg32Float
+        case kCVPixelFormatType_32BGRA:
+            return .bgra8Unorm
+        case kCVPixelFormatType_32RGBA:
+            return .rgba8Unorm
+        case kCVPixelFormatType_64RGBAHalf:
+            return .rgba16Float
+        case kCVPixelFormatType_128RGBAFloat:
+            return .rgba32Float
+        case kCVPixelFormatType_ARGB2101010LEPacked:
+            return .bgr10a2Unorm
+        default:
+            return nil
+        }
+    }
+}

libobs-metal/MTLCullMode+Extensions.swift

@@ -0,0 +1,33 @@
+/******************************************************************************
+ Copyright (C) 2024 by Patrick Heyer <PatTheMav@users.noreply.github.com>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ ******************************************************************************/
+
+import Foundation
+import Metal
+
+extension MTLCullMode {
+    /// Conversion of the cull mode into its corresponding `libobs` type
+    var obsMode: gs_cull_mode {
+        switch self {
+        case .back:
+            return GS_BACK
+        case .front:
+            return GS_FRONT
+        default:
+            return GS_NEITHER
+        }
+    }
+}

libobs-metal/MTLOrigin+Extensions.swift

@@ -0,0 +1,25 @@
+/******************************************************************************
+ Copyright (C) 2024 by Patrick Heyer <PatTheMav@users.noreply.github.com>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ ******************************************************************************/
+
+import Foundation
+import Metal
+
+extension MTLOrigin: @retroactive Equatable {
+    public static func == (lhs: MTLOrigin, rhs: MTLOrigin) -> Bool {
+        lhs.x == rhs.x && lhs.y == rhs.y && lhs.z == rhs.z
+    }
+}