Add rendering stuff, cross-platform support, camera controller & SDL input logic

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "engine/native/thirdparty/bgfx"]
 	path = engine/native/thirdparty/bgfx
 	url = https://github.com/bkaradzic/bgfx
+[submodule "engine/native/thirdparty/sdl"]
+	path = engine/native/thirdparty/sdl
+	url = https://github.com/libsdl-org/SDL

CMakeLists.txt

@@ -25,13 +25,53 @@ endif()
 
 project(DraconicEngine LANGUAGES C CXX)
 
+# Ensure that everyone is on the same page hardware wise or else we get errors
+if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+    add_compile_options(-mavx2 -mfma)
+endif()
+
 # Only have safe global rules here
 set(CMAKE_CXX_STANDARD 23)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_MODULE_STD ON)
+set(CMAKE_POSITION_INDEPENDENT_CODE ON) # bgfx & deps give error if this isn't set, this is a temp workaround
+# Force all to use Clang or else a mismatch occurs
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
+set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -stdlib=libc++ -lc++abi")
 
 list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/cmake")
 
 include(CTest)
 
-add_subdirectory(engine/native)
+add_subdirectory(engine/native)
+
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(X11_LIBS REQUIRED IMPORTED_TARGET x11 xext xcursor xrandr xrender xi xfixes)
+
+add_executable(draconic engine/native/main/main.cpp)
+enable_modules(draconic)
+target_link_libraries(draconic
+    PRIVATE
+    rhi
+    core
+    bgfx
+    bx
+    bimg
+    -Wl,--whole-archive SDL3::SDL3-static -Wl,--no-whole-archive
+    c++ 
+    c++abi
+    PkgConfig::X11_LIBS
+    dl 
+    pthread 
+    m
+)
+
+# Shader copying
+set(ENGINE_SHADER_DIR "${CMAKE_SOURCE_DIR}/engine/native/rendering/shaders")
+add_custom_command(
+    TARGET draconic POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E copy_directory
+        "${ENGINE_SHADER_DIR}"
+        "$<TARGET_FILE_DIR:draconic>"
+    COMMENT "Copying shaders to build directory..."
+)

CMakePresets.json

@@ -21,7 +21,6 @@
         "CMAKE_CXX_STANDARD": "23",
         "CMAKE_CXX_STANDARD_REQUIRED": "ON",
         "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_MODULE_STD": "1",
         "CMAKE_CXX_FLAGS_INIT": "-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0"
       }
     },

cmake/Compiler.cmake

@@ -15,12 +15,6 @@ else()
     add_compile_definitions(DEBUG)
 endif()
 
-# Force Clang to use libc++
-if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-    add_compile_options(-stdlib=libc++)
-    add_link_options(-stdlib=libc++)
-endif()
-
 if (CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
     if (CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64|AMD64")
         # TODO: Make SIMD level configurable or detect at runtime

engine/native/CMakeLists.txt

@@ -4,4 +4,6 @@ include(Modules)
 add_subdirectory(thirdparty)
 
 add_modules_library(core SHARED)
-target_link_libraries(core PUBLIC definitions math)
+target_link_libraries(core PUBLIC definitions math filesystem)
+
+add_subdirectory(rendering)

engine/native/core/CMakeLists.txt

@@ -1,3 +1,5 @@
 add_modules_library(definitions)
 add_modules_library(math)
-target_link_libraries(math PUBLIC definitions)
+add_modules_library(filesystem)
+target_link_libraries(math PUBLIC definitions)
+target_link_libraries(filesystem PUBLIC definitions)

engine/native/core/filesystem/filesystem.cpp

@@ -0,0 +1,36 @@
+module;
+
+import std;
+
+module core.filesystem;
+
+namespace draco::filesystem
+{
+    std::vector<std::uint8_t> load_binary(const std::string& path)
+    {
+        // Open at the end (ate) to get size and in binary mode
+        std::ifstream file(path, std::ios::binary | std::ios::ate);
+
+        if (!file.is_open()) {
+            std::println("Error: Could not open file at: {}", path);
+            // Return an empty vector
+            return {}; 
+        }
+
+        std::streamsize size = file.tellg();
+        if (size <= 0) {
+            std::println("Error: File is empty or unreadable: {}", path);
+            return {};
+        }
+
+        file.seekg(0, std::ios::beg);
+
+        std::vector<std::uint8_t> buffer(static_cast<std::size_t>(size));
+        if (file.read(reinterpret_cast<char*>(buffer.data()), size)) {
+            return buffer;
+        }
+
+        std::println("Error: Failed to read file contents: {}", path);
+        return {};
+    }
+}

engine/native/core/filesystem/filesystem.cppm

@@ -0,0 +1,9 @@
+export module core.filesystem;
+
+import std;
+
+export namespace draco::filesystem
+{
+    // Returns a buffer of the file data
+    std::vector<std::uint8_t> load_binary(const std::string& path);
+}

engine/native/main/main.cpp

@@ -0,0 +1,137 @@
+import std;
+
+#include <SDL3/SDL.h>
+#include <bgfx/bgfx.h>
+#include <bx/math.h>
+
+import core.filesystem;
+
+import rendering.rhi;
+import rendering.rhi.vertex;
+
+int main(int argc, char* argv[])
+{
+    if (!SDL_Init(SDL_INIT_VIDEO)) {
+        std::println("SDL init failed: {}", SDL_GetError());
+        return -1;
+    }
+
+    SDL_Window* window = SDL_CreateWindow(
+        "Draconic Engine",
+        1280, 720,
+        SDL_WINDOW_RESIZABLE
+    );
+
+    if (!window) {
+        std::println("Failed to create window: {}", SDL_GetError());
+        return -1;
+    }
+
+    const char* driver = SDL_GetCurrentVideoDriver();
+    std::println("Driver: {}", driver ? driver : "Unknown");
+
+    void* nwh = nullptr; // Native window handle
+    void* ndt = nullptr; // Native display type
+
+#if defined(__linux__)
+
+    SDL_PropertiesID props = SDL_GetWindowProperties(window);
+
+    if (driver && std::string_view(driver) == "x11")
+    {
+        ndt = SDL_GetPointerProperty(props, SDL_PROP_WINDOW_X11_DISPLAY_POINTER, nullptr); // Get the X11 display pointer
+        nwh = (void*)(uintptr_t)SDL_GetNumberProperty(props, SDL_PROP_WINDOW_X11_WINDOW_NUMBER, 0); // Get the X11 window number and cast it to a pointer
+    }
+
+#endif
+
+    if (!nwh) {
+        std::println("Failed to get native window handle");
+        return -1;
+    }
+
+    if(!ndt) {
+        std::println("Failed to get native display type");
+        return -1;
+    }
+
+    // Init the RHI with the native window handle and initial size
+    if (!draco::rhi::init(ndt, nwh, 1280, 720)) {
+        std::println("Failed to initialize RHI");
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return -1;
+    }
+
+    // Geometry data for a triangle to test rendering
+    // It includes both positions & colors
+    draco::rhi::PosColorVertex triangle[] = {
+        { 0.0f, 0.5f, 0.0f, 0xff0000ff }, 
+        { 0.5f, -0.5f, 0.0f, 0xff00ff00 },
+        { -0.5f, -0.5f, 0.0f, 0xffff0000}
+    };
+
+    auto vbh = draco::rhi::create_vertex_buffer(triangle, sizeof(triangle));
+
+    // Load the vertex & fragment shaders
+    auto vs_data = draco::filesystem::load_binary("vs_triangle.bin");
+    auto fs_data = draco::filesystem::load_binary("fs_triangle.bin");
+
+    // If the path is empty, return an error
+    if (vs_data.empty() || fs_data.empty()) {
+        std::println("Failed to load shaders");
+        std::println("Workin' dir: {}", std::filesystem::current_path().string());
+        draco::rhi::shutdown();
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return -1;
+    }
+
+    auto vsh = draco::rhi::create_shader(vs_data.data(), (uint32_t)vs_data.size());
+    auto fsh = draco::rhi::create_shader(fs_data.data(), (uint32_t)fs_data.size());
+
+
+    // TODO: Expose our own macros for the state flags instead of using bgfx's directly, tis is just for testin'
+    auto pipeline = draco::rhi::create_pipeline({vsh, fsh, (0 
+        | BGFX_STATE_WRITE_RGB 
+        | BGFX_STATE_WRITE_A 
+        | BGFX_STATE_MSAA 
+        | BGFX_STATE_PT_TRISTRIP)});
+
+    bool running = true;
+
+    while (running)
+    {
+        SDL_Event event;
+        while (SDL_PollEvent(&event))
+        {
+            if (event.type == SDL_EVENT_QUIT)
+                running = false;
+        }
+
+        int w, h;
+        SDL_GetWindowSize(window, &w, &h);
+
+        draco::rhi::resize(uint16_t(w), uint16_t(h));
+
+        draco::rhi::begin_frame();
+
+        draco::rhi::RenderPacket packet{};
+        packet.vertex_buffer = vbh;
+        packet.index_buffer = UINT16_MAX;  // No index buffer
+        packet.pipeline = pipeline;
+        bx::mtxIdentity(packet.model);
+
+        draco::rhi::submit(packet, 0);
+
+        draco::rhi::end_frame();
+    }
+
+    draco::rhi::shutdown();
+
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    return 0;
+}
+
+// Fun fact: AR literally went mad & tis is the result

engine/native/rendering/CMakeLists.txt

@@ -0,0 +1,3 @@
+add_modules_library(rhi SHARED)
+target_sources(rhi PRIVATE rhi/rhi_bgfx.cpp rhi/vertex.cppm)
+target_link_libraries(rhi PUBLIC core bgfx bx)

engine/native/rendering/rhi/rhi.cppm

@@ -0,0 +1,46 @@
+export module rendering.rhi;
+
+#include <cstdint>
+
+export namespace draco::rhi
+{
+    using BufferHandle   = uint16_t;
+    using PipelineHandle = uint16_t;
+    using ShaderHandle   = uint16_t;
+    using ViewID         = uint16_t;
+
+    struct RenderPacket
+    {
+        uint64_t sort_key;
+
+        BufferHandle vertex_buffer;
+        BufferHandle index_buffer;
+        PipelineHandle pipeline;
+
+        float model[16];
+        uint32_t draw_tags;
+    };
+
+    struct PipelineDesc
+    {
+        ShaderHandle vs;
+        ShaderHandle fs;
+        uint64_t state;
+    };
+
+    bool init(void* display_type, void* window_handle, uint16_t width, uint16_t height);
+    void shutdown();
+
+    void resize(uint16_t width, uint16_t height);
+
+    ShaderHandle create_shader(const void* data, uint32_t size);
+    PipelineHandle create_pipeline(const PipelineDesc&);
+
+    BufferHandle create_vertex_buffer(const void* data, uint32_t size);
+    BufferHandle create_index_buffer(const void* data, uint32_t size);
+
+    void submit(const RenderPacket&, ViewID);
+
+    void begin_frame();
+    void end_frame();
+}