Add experimental SDL backend for Linux

engine/gfx/vulkan/src/gfx_vulkan.cpp

@@ -18,6 +18,12 @@
 #include "utility.hpp"
 #include "gfx_vulkan_commandbuffer.hpp"
 
+#ifdef PLATFORM_LINUX
+#include <SDL2/SDL.h>
+#include <platform.hpp>
+
+#endif
+
 VkFormat toVkFormat(GFXPixelFormat format) {
 	switch (format) {
     case GFXPixelFormat::R_32F:
@@ -180,8 +186,6 @@ VkResult name_object(VkDevice device, VkObjectType type, uint64_t object, std::s
 bool GFXVulkan::initialize(const GFXCreateInfo& info) {
 #ifdef PLATFORM_WINDOWS
     const char* surface_name = "VK_KHR_win32_surface";
-#else
-    const char* surface_name = VK_KHR_XCB_SURFACE_EXTENSION_NAME;
 #endif
 
 	uint32_t extensionPropertyCount = 0;
@@ -190,12 +194,15 @@ bool GFXVulkan::initialize(const GFXCreateInfo& info) {
 	std::vector<VkExtensionProperties> extensionProperties(extensionPropertyCount);
 	vkEnumerateInstanceExtensionProperties(nullptr, &extensionPropertyCount, extensionProperties.data());
 
-	std::vector<const char*> enabledExtensions = { "VK_KHR_surface", surface_name };
+	std::vector<const char*> enabledExtensions = {};
 	for (auto prop : extensionProperties) {
 		if (!strcmp(prop.extensionName, "VK_EXT_debug_utils"))
 			enabledExtensions.push_back("VK_EXT_debug_utils");
 	}
 
+	auto required_extensions = platform::get_native_surface_extension();
+	enabledExtensions.insert(enabledExtensions.end(), required_extensions.begin(), required_extensions.end());
+
 	createInstance({}, enabledExtensions);
 	createLogicalDevice({ VK_KHR_SWAPCHAIN_EXTENSION_NAME });
 	createDescriptorPool();
@@ -1450,20 +1457,7 @@ void GFXVulkan::createSwapchain(NativeSurface* native_surface, VkSwapchainKHR ol
 	}
 #else
     if(native_surface->surface == VK_NULL_HANDLE) {
-        struct WindowConnection {
-            int identifier = 0;
-            xcb_connection_t* connection;
-            xcb_window_t window;
-        };
-
-        WindowConnection* wincon = reinterpret_cast<WindowConnection*>(native_surface->windowNativeHandle);
-
-        VkXcbSurfaceCreateInfoKHR createInfo = {};
-        createInfo.sType = VK_STRUCTURE_TYPE_XCB_SURFACE_CREATE_INFO_KHR;
-        createInfo.window = wincon->window;
-        createInfo.connection = wincon->connection;
-
-        vkCreateXcbSurfaceKHR(instance, &createInfo, nullptr, &native_surface->surface);
+        native_surface->surface = (VkSurfaceKHR)platform::create_native_surface(native_surface->identifier, (void*)instance);
     }
 #endif
 

engine/platform/include/platform.hpp

@@ -84,6 +84,10 @@ namespace platform {
      */
     int open_window(const std::string_view title, const prism::Rectangle rect, const WindowFlags flags);
 
+    // for vulkan usage
+    void* create_native_surface(int index, void* instance);
+    std::vector<const char*> get_native_surface_extension();
+
     /** Closes a window.
      @param index The window to close.
      */

platforms/CMakeLists.txt

@@ -3,17 +3,17 @@ if(ENABLE_WINDOWS)
 endif()
 
 if(ENABLE_LINUX)
-	add_subdirectory(linux)
+	add_subdirectory(sdl)
 endif()
 
 if(ENABLE_MACOS)
 	add_subdirectory(mac)
-endif()
-
+endif()
+
 if(ENABLE_IOS)
 	add_subdirectory(ios)
-endif()
-
+endif()
+
 if(ENABLE_TVOS)
 	add_subdirectory(tvos)
 endif()

platforms/sdl/CMakeLists.txt

@@ -0,0 +1,21 @@
+include(../../cmake/AddPlatformExecutable.cmake)
+
+add_platform(
+        SRC ${CMAKE_CURRENT_SOURCE_DIR}/file.cpp
+        MAIN_FILE
+        main.cpp.in
+        LINK_LIBRARIES
+        SDL2
+        Core
+        GFXVulkan
+)
+
+function(add_platform_commands target)
+    if(NOT SKIP_DATA)
+        add_custom_command(TARGET ${target} POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_SOURCE_DIR}/data $<TARGET_FILE_DIR:${target}>/data)
+    endif()
+
+    add_custom_command(TARGET ${target} PRE_BUILD COMMAND ${CMAKE_COMMAND} -E make_directory $<TARGET_FILE_DIR:${target}>/shaders)
+
+    add_custom_command(TARGET ${target} POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_BINARY_DIR}/shaders $<TARGET_FILE_DIR:${target}>/shaders)
+endfunction()

platforms/sdl/file.cpp

@@ -0,0 +1,11 @@
+#include "file.hpp"
+
+#include "string_utils.hpp"
+
+void file::set_domain_path(const file::Domain domain, const file::Path path) {
+    domain_data[(int)domain] = replace_substring(path.string(), "{resource_dir}/", "");
+}
+
+file::Path file::get_writeable_directory() {
+    return "~";
+}

platforms/sdl/main.cpp.in

@@ -0,0 +1,243 @@
+#include <@APP_INCLUDE@>
+#include <engine.hpp>
+
+#include "gfx_vulkan.hpp"
+#include "platform.hpp"
+
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_vulkan.h>
+
+@APP_CLASS@* app = nullptr;
+GFX* interface = nullptr;
+
+struct Window {
+    int identifier = 0;
+    SDL_Window* window = nullptr;
+};
+
+std::vector<Window> windows;
+
+static std::map<InputButton, int> inputToKeyCode = { {
+    {InputButton::A, 38},
+    {InputButton::W, 25},
+    {InputButton::S, 39},
+    {InputButton::D, 40},
+    {InputButton::Q, 24}
+}};
+
+/*
+ * Platform functions"
+ */
+
+const char* platform::get_name() {
+    return "Linux (SDL)";
+}
+
+bool platform::supports_feature(const PlatformFeature feature) {
+    if(feature == PlatformFeature::Windowing)
+        return true;
+
+    return false;
+}
+
+int platform::open_window(const std::string_view title, const prism::Rectangle rect, const WindowFlags flags) {
+    auto& win = windows.emplace_back();
+    win.identifier = windows.size() - 1;
+
+    win.window = SDL_CreateWindow(title.data(), rect.offset.x, rect.offset.y, rect.extent.width, rect.extent.height, SDL_WINDOW_VULKAN);
+
+    engine->add_window((void*)&win, 0, rect.extent);
+    app->initialize_render();
+
+    return win.identifier;
+}
+
+void platform::close_window(const int index) {
+}
+
+void platform::force_quit() {
+}
+
+float platform::get_window_dpi(const int index) {
+    return 1.0;
+}
+
+float platform::get_monitor_dpi() {
+    return 1.0;
+}
+
+prism::Rectangle platform::get_monitor_resolution() {
+    return {};
+}
+
+prism::Rectangle platform::get_monitor_work_area() {
+    return platform::get_monitor_resolution();
+}
+
+Window* get_window(const int index) {
+    for(auto& window : windows) {
+        if(window.identifier == index)
+            return &window;
+    }
+
+    return nullptr;
+}
+
+prism::Offset platform::get_window_position(const int index) {
+}
+
+prism::Extent platform::get_window_size(const int index) {
+    auto window = get_window(index);
+
+    int width, height;
+    SDL_GetWindowSize(window->window, &width, &height);
+
+    return {(uint32_t)width, (uint32_t)height};
+}
+
+prism::Extent platform::get_window_drawable_size(const int index) {
+    auto window = get_window(index);
+
+    int width, height;
+    SDL_GetWindowSize(window->window, &width, &height);
+
+    return {(uint32_t)width, (uint32_t)height};
+}
+
+bool platform::is_window_focused(const int index) {
+}
+
+void platform::set_window_focused(const int index) {
+}
+
+void platform::set_window_position(const int index, const prism::Offset offset) {
+}
+
+void platform::set_window_size(const int index, const prism::Extent extent) {
+}
+
+void platform::set_window_title(const int index, const std::string_view title) {
+    auto window = get_window(index);
+
+    SDL_SetWindowTitle(window->window, title.data());
+}
+
+bool platform::get_key_down(const InputButton key) {
+    return false;
+}
+
+int platform::get_keycode(const InputButton key) {
+    return inputToKeyCode[key];
+}
+
+prism::Offset platform::get_cursor_position() {
+    return {0, 0};
+}
+
+prism::Offset platform::get_screen_cursor_position() {
+    return {0, 0};
+}
+
+bool platform::get_mouse_button_down(const int button) {
+    return false;
+}
+
+std::tuple<float, float> platform::get_wheel_delta() {
+}
+
+std::tuple<float, float> platform::get_right_stick_position() {
+}
+
+std::tuple<float, float> platform::get_left_stick_position() {
+}
+
+void platform::capture_mouse(const bool capture) {
+}
+
+void platform::open_dialog(const bool existing, std::function<void(std::string)> returnFunction, bool openDirectory) {
+}
+
+void platform::save_dialog(std::function<void(std::string)> returnFunction) {
+}
+
+char* platform::translate_keycode(const unsigned int keycode) {
+    return "";
+}
+
+int stdout_copy;
+int stderr_copy;
+
+void platform::mute_output() {
+
+}
+
+void platform::unmute_output() {
+
+}
+
+int main(int argc, char* argv[]) {
+    SDL_Init(SDL_INIT_VIDEO);
+
+    engine = new Engine(argc, argv);
+
+    app = new @APP_CLASS@();
+    engine->set_app(app);
+
+    GFXCreateInfo info = {};
+
+    interface = new GFXVulkan();
+    if(interface->initialize(info)) {
+        engine->set_gfx(interface);
+    } else {
+        return -1;
+    }
+
+    app_main(engine);
+
+    while(1) {
+         SDL_Event event = {};
+         while(SDL_PollEvent(&event)) {
+
+         }
+
+         if(engine->is_quitting())
+             break;
+
+         engine->update(1.0 / 60.0);
+         engine->begin_frame(1.0 / 60.0);
+         engine->render(0);
+
+         engine->end_frame();
+     }
+
+  return 0;
+}
+
+PlatformTheme platform::get_theme() {
+    return PlatformTheme::Light;
+}
+
+void* platform::create_native_surface(int index, void* instance) {
+    auto window = get_window(index);
+
+    VkSurfaceKHR surface;
+
+    SDL_Vulkan_CreateSurface(window->window, (VkInstance)instance, &surface);
+
+    return surface;
+}
+
+std::vector<const char*> platform::get_native_surface_extension() {
+    // dummy window
+    auto dummy = SDL_CreateWindow("", 0, 0, 1, 1, SDL_WINDOW_VULKAN);
+
+    unsigned int count = 0;
+    SDL_Vulkan_GetInstanceExtensions(dummy, &count, nullptr);
+
+    std::vector<const char*> extensions(count);
+    SDL_Vulkan_GetInstanceExtensions(dummy, &count, extensions.data());
+
+    SDL_DestroyWindow(dummy);
+
+    return extensions;
+}