Enable using MoltenVK on macOS (#2846)

Co-authored-by: Adrian Cojocaru <adrian.cojocaru92@yahoo.com>

include/mbgl/vulkan/renderer_backend.hpp

@@ -3,13 +3,14 @@
 #include <mbgl/gfx/renderer_backend.hpp>
 #include <mbgl/gfx/context.hpp>
 
+#define VULKAN_HPP_DISPATCH_LOADER_DYNAMIC 1
+
 #ifdef _WIN32
 #define VK_USE_PLATFORM_WIN32_KHR
 #elif defined(__ANDROID__)
 #define VK_USE_PLATFORM_ANDROID_KHR
 #endif
 
-#define VULKAN_HPP_DISPATCH_LOADER_DYNAMIC 1
 #include <vulkan/vulkan.hpp>
 
 #define VMA_VULKAN_VERSION 1000000

platform/glfw/glfw_view.cpp

@@ -215,7 +215,7 @@ GLFWView::GLFWView(bool fullscreen_,
     bool capFrameRate = !benchmark; // disable VSync in benchmark mode
     backend = GLFWBackend::Create(window, capFrameRate);
 
-#ifdef __APPLE__
+#if defined(__APPLE__) && !defined(MLN_RENDER_BACKEND_VULKAN)
     int fbW, fbH;
     glfwGetFramebufferSize(window, &fbW, &fbH);
     backend->setSize({static_cast<uint32_t>(fbW), static_cast<uint32_t>(fbH)});

platform/macos/macos.cmake

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.19)
-set(CMAKE_OSX_DEPLOYMENT_TARGET "10.15")
+set(CMAKE_OSX_DEPLOYMENT_TARGET "14.3")
 
 # Override default CMake NATIVE_ARCH_ACTUAL
 # https://gitlab.kitware.com/cmake/cmake/-/issues/20893
@@ -40,6 +40,26 @@ if(MLN_WITH_METAL)
     )
 endif()
 
+if(MLN_WITH_VULKAN)
+    find_package(Vulkan REQUIRED)
+
+    target_sources(
+        mbgl-core
+        PRIVATE
+            ${PROJECT_SOURCE_DIR}/platform/default/src/mbgl/vulkan/headless_backend.cpp
+    )
+
+    if(Vulkan_FOUND)
+        get_filename_component(Vulkan_LIBRARY_DIR ${Vulkan_LIBRARY} DIRECTORY)
+        set(CMAKE_INSTALL_RPATH ${Vulkan_LIBRARY_DIR})
+    else()
+        set(CMAKE_INSTALL_RPATH "/usr/local/lib/")
+        message(STATUS "Vulkan SDK not found! Using default homebrew install path")
+    endif()
+
+    set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
+endif()
+
 target_sources(
     mbgl-core
     PRIVATE

src/mbgl/vulkan/renderer_backend.cpp

@@ -102,11 +102,21 @@ std::vector<const char*> RendererBackend::getLayers() {
 }
 
 std::vector<const char*> RendererBackend::getInstanceExtensions() {
-    return {};
+    return {
+#ifdef __APPLE__
+        "VK_KHR_portability_enumeration"
+#endif
+    };
 }
 
 std::vector<const char*> RendererBackend::getDeviceExtensions() {
-    return getDefaultRenderable().getResource<SurfaceRenderableResource>().getDeviceExtensions();
+    auto extensions = getDefaultRenderable().getResource<SurfaceRenderableResource>().getDeviceExtensions();
+
+#ifdef __APPLE__
+    extensions.push_back("VK_KHR_portability_subset");
+#endif
+
+    return extensions;
 }
 
 std::vector<const char*> RendererBackend::getDebugExtensions() {
@@ -323,8 +333,14 @@ void RendererBackend::initInstance() {
 
     // Vulkan 1.1 on Android is supported on 71% of devices (compared to 1.3 with 6%) as of April 23 2024
     // https://vulkan.gpuinfo.org/
+#ifdef __APPLE__
+    vk::InstanceCreateFlags instanceFlags = vk::InstanceCreateFlagBits::eEnumeratePortabilityKHR;
+#else
+    vk::InstanceCreateFlags instanceFlags = {};
+#endif
+
     vk::ApplicationInfo appInfo("maplibre-native", 1, "maplibre-native", 1, VK_API_VERSION_1_0);
-    vk::InstanceCreateInfo createInfo(vk::InstanceCreateFlags(), &appInfo);
+    vk::InstanceCreateInfo createInfo(instanceFlags, &appInfo);
 
     const auto& layers = getLayers();
 
@@ -501,7 +517,7 @@ void RendererBackend::initDevice() {
     // TODO
     // - WideLines disabled on Android (20.77% device coverage https://vulkan.gpuinfo.org/listfeaturescore10.php)
     // - Rework this to a dynamic toggle based on MLN_TRIANGULATE_FILL_OUTLINES/MLN_ENABLE_POLYLINE_DRAWABLES
-#if !defined(__ANDROID__) && !defined(__apple__)
+#if !defined(__ANDROID__) && !defined(__APPLE__)
     if (supportedDeviceFeatures.wideLines) {
         physicalDeviceFeatures.setWideLines(true);