Vulkan embedder GLFW example (flutter#31213)

BUILD.gn

@@ -82,7 +82,10 @@ group("flutter") {
 
   # Ensure the example for a sample embedder compiles.
   if (build_embedder_examples) {
-    public_deps += [ "//flutter/examples/glfw" ]
+    public_deps += [
+      "//flutter/examples/glfw",
+      "//flutter/examples/vulkan_glfw",
+    ]
   }
 
   # If enbaled, compile the SDK / snapshot.

examples/vulkan_glfw/.gitignore

@@ -0,0 +1 @@
+debug/

examples/vulkan_glfw/BUILD.gn

@@ -0,0 +1,16 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+executable("vulkan_glfw") {
+  output_name = "embedder_example_vulkan"
+
+  sources = [ "src/main.cc" ]
+
+  configs += [ "//flutter/vulkan:vulkan_config" ]
+
+  deps = [
+    "//flutter/shell/platform/embedder:embedder",
+    "//third_party/glfw",
+  ]
+}

examples/vulkan_glfw/CMakeLists.txt

@@ -0,0 +1,64 @@
+cmake_minimum_required(VERSION 3.15)
+project(FlutterEmbedderVulkanGLFW)
+
+set(CMAKE_CXX_STANDARD 17)
+
+# Primary target
+
+set(EXE_NAME embedder_example_vulkan)
+
+file(GLOB_RECURSE SOURCE_FILES "src/*.cc" "src/*.h")
+add_executable(${EXE_NAME} ${SOURCE_FILES})
+
+
+# Dependency: Vulkan SDK
+
+# Override the SDK location by using the VULKAN_SDK environment variable.
+# The VULKAN_SDK path should contain `include/vulkan/vulkan.hpp`.
+#
+# MacOS MoltenVK Vulkan SDK environment example:
+#  export VULKAN_SDK=~/VulkanSDK/1.2.198.1/macOS
+#  export VK_LOADER_DEBUG=all
+#  export VK_ICD_FILENAMES=$VULKAN_SDK/share/vulkan/icd.d/MoltenVK_icd.json
+#  export VK_LAYER_PATH=$VULKAN_SDK/share/vulkan/explicit_layer.d
+#  export DYLD_LIBRARY_PATH=$VULKAN_SDK/lib:$DYLD_LIBRARY_PATH
+
+find_package(Vulkan REQUIRED)
+target_include_directories(${EXE_NAME} PRIVATE ${Vulkan_INCLUDE_DIRS})
+target_link_libraries(${EXE_NAME} PRIVATE Vulkan::Vulkan)
+
+
+# Dependency: GLFW
+
+set(GLFW_REPOSITORY ${CMAKE_SOURCE_DIR}/../../../third_party/glfw)
+
+set(BUILD_SHARED_LIBS OFF)
+set(GLFW_BUILD_DOCS OFF CACHE BOOL "" FORCE)
+set(GLFW_BUILD_TESTS OFF CACHE BOOL "" FORCE)
+set(GLFW_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
+set(GLFW_VULKAN_STATIC OFF CACHE BOOL "" FORCE)
+add_subdirectory(${GLFW_REPOSITORY} build_glfw)
+
+target_link_libraries(${EXE_NAME} PRIVATE glfw)
+target_include_directories(${EXE_NAME} PRIVATE $(GLFW_REPOSITORY)/include)
+
+
+# Dependency: Flutter Engine
+
+# This is assuming you've built a local version of the Flutter Engine. If you
+# downloaded yours from the internet you'll have to change this.
+set(EMBEDDER_H_DIR ${CMAKE_SOURCE_DIR}/../../shell/platform/embedder)
+set(FLUTTER_OUT_DIR ${CMAKE_SOURCE_DIR}/../../../out/host_debug_unopt)
+
+find_library(FLUTTER_LIB flutter_engine PATHS ${FLUTTER_OUT_DIR})
+
+target_link_libraries(${EXE_NAME} PRIVATE ${FLUTTER_LIB})
+target_include_directories(${EXE_NAME} PRIVATE ${EMBEDDER_H_DIR})
+
+# Copy the flutter library here since the shared library
+# name is `./libflutter_engine.dylib`.
+add_custom_command(
+        TARGET ${EXE_NAME} POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E copy
+                ${FLUTTER_LIB}
+                ${CMAKE_CURRENT_BINARY_DIR})

examples/vulkan_glfw/run.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+set -xe
+
+#################################################################
+# Make the host C++ project.
+#################################################################
+cmake -Bdebug -DCMAKE_BUILD_TYPE=Debug
+pushd debug > /dev/null
+make
+
+#################################################################
+# Make the guest Flutter project.
+#################################################################
+if [ ! -d myapp ]; then
+    flutter create myapp
+fi
+pushd myapp > /dev/null
+#cp ../../main.dart lib/main.dart
+flutter build bundle
+popd > /dev/null
+
+#################################################################
+# Run the Flutter Engine Embedder
+#################################################################
+./embedder_example_vulkan ./myapp ../../../../third_party/icu/common/icudtl.dat
+
+popd > /dev/null