Aka Engine

Small 3D game engine, mainly built for personal educational purpose, to be easy to use and to extend. It was at start a small engine for 2D game developement with OpenGL and it suddenly became a 3D engine with Vulkan...

Aka stand for red in japanese (赤) and there is no particular reason for this name, we just need one !

Features

• Platform backend with GLFW 3.2
• Graphic backend with Vulkan / D3D12 (WIP)
• Audio backend with RtAudio (mp3 support)
• Event system for intersystem communication
• UTF8 support
• Cross platform (should be easily compiled)
• EC system with component pools.
• Memory tracking
• Asset manager
• Static & skeletal meshes

How to use

This basic example create a window and spin a cube in the middle of the screen.

#include <Aka/Aka.h>

using namespace aka;

static float vertices[] = {
	-1.0f,  1.0f, -1.0f,	0.f, 1.f,
	-1.0f, -1.0f, -1.0f,	0.f, 0.f,
	 1.0f, -1.0f, -1.0f,	1.f, 0.f,
	 1.0f, -1.0f, -1.0f,	1.f, 0.f,
	 1.0f,  1.0f, -1.0f,	1.f, 1.f,
	-1.0f,  1.0f, -1.0f,	0.f, 1.f,

	-1.0f, -1.0f,  1.0f,	0.f, 1.f,
	-1.0f, -1.0f, -1.0f,	0.f, 0.f,
	-1.0f,  1.0f, -1.0f,	1.f, 0.f,
	-1.0f,  1.0f, -1.0f,	1.f, 0.f,
	-1.0f,  1.0f,  1.0f,	1.f, 1.f,
	-1.0f, -1.0f,  1.0f,	0.f, 1.f,

	 1.0f, -1.0f, -1.0f,	0.f, 0.f,
	 1.0f, -1.0f,  1.0f,	0.f, 1.f,
	 1.0f,  1.0f,  1.0f,	1.f, 1.f,
	 1.0f,  1.0f,  1.0f,	1.f, 1.f,
	 1.0f,  1.0f, -1.0f,	1.f, 0.f,
	 1.0f, -1.0f, -1.0f,	0.f, 0.f,

	-1.0f, -1.0f,  1.0f,	0.f, 0.f,
	-1.0f,  1.0f,  1.0f,	0.f, 1.f,
	 1.0f,  1.0f,  1.0f,	1.f, 1.f,
	 1.0f,  1.0f,  1.0f,	1.f, 1.f,
	 1.0f, -1.0f,  1.0f,	1.f, 0.f,
	-1.0f, -1.0f,  1.0f,	0.f, 0.f,

	-1.0f,  1.0f, -1.0f,	0.f, 0.f,
	 1.0f,  1.0f, -1.0f,	1.f, 0.f,
	 1.0f,  1.0f,  1.0f,	1.f, 1.f,
	 1.0f,  1.0f,  1.0f,	1.f, 1.f,
	-1.0f,  1.0f,  1.0f,	0.f, 1.f,
	-1.0f,  1.0f, -1.0f,	0.f, 0.f,

	-1.0f, -1.0f, -1.0f,	0.f, 0.f,
	-1.0f, -1.0f,  1.0f,	0.f, 1.f,
	 1.0f, -1.0f, -1.0f,	1.f, 0.f,
	 1.0f, -1.0f, -1.0f,	1.f, 0.f,
	-1.0f, -1.0f,  1.0f,	0.f, 1.f,
	 1.0f, -1.0f,  1.0f,	1.f, 1.f,
};

struct Game :
	Application,
	EventListener<KeyboardKeyDownEvent>
{
	gfx::BufferHandle ubo = gfx::BufferHandle::null;
	gfx::BufferHandle vertexBuffer = gfx::BufferHandle::null;
	gfx::ShaderHandle vertex = gfx::ShaderHandle::null;
	gfx::ShaderHandle fragment = gfx::ShaderHandle::null;
	gfx::ProgramHandle programHandle = gfx::ProgramHandle::null;
	gfx::GraphicPipelineHandle pipeline = gfx::GraphicPipelineHandle::null;
	gfx::DescriptorPoolHandle pool = gfx::DescriptorPoolHandle::null;
	gfx::DescriptorSetHandle set = gfx::DescriptorSetHandle::null;
	gfx::RenderPassHandle renderPass = gfx::RenderPassHandle::null;
	gfx::BackbufferHandle backbuffer = gfx::BackbufferHandle::null;
	anglef rotation = anglef::radian(0.f);
	struct UBO {
		mat4f model;
		mat4f view;
		mat4f projection;
	};
	Game(const Config& cfg) : Application(cfg) {}
	void onCreate(int argc, char* argv[]) override {
		// Register our shader in registry for hot reload & co.
		ShaderKey vertexShader = ShaderKey::generate(AssetPath("shaders/shader.vert"), gfx::ShaderType::Vertex);
		ShaderKey fragShader = ShaderKey::generate(AssetPath("shaders/shader.frag"), gfx::ShaderType::Fragment);
		ProgramKey programKey = ProgramKey{}.add(vertexShader).add(fragShader);
		UBO uboData;
		uboData.model = mat4f::identity();
		uboData.view = mat4f::lookAtView(point3f(3), point3f(0));
		uboData.projection = mat4f::perspective(anglef::degree(60.f), width() / (float)height(), 0.1f, 100.f);
		ubo = graphic()->createBuffer("UBO", gfx::BufferType::Uniform, sizeof(UBO), gfx::BufferUsage::Default, gfx::BufferCPUAccess::None, &uboData);
		// Create mesh
		gfx::VertexBufferLayout vertexLayout;
		vertexLayout.add(gfx::VertexSemantic::Position, gfx::VertexFormat::Float, gfx::VertexType::Vec3);
		vertexLayout.add(gfx::VertexSemantic::TexCoord0, gfx::VertexFormat::Float, gfx::VertexType::Vec2);
		vertexBuffer = graphic()->createBuffer("Vertices", gfx::BufferType::Vertex, sizeof(vertices), gfx::BufferUsage::Default, gfx::BufferCPUAccess::None, vertices);
		// Shaders
		gfx::ShaderBindingState state = gfx::ShaderBindingState().add(gfx::ShaderBindingType::UniformBuffer, gfx::ShaderMask::Vertex);
		gfx::ShaderPipelineLayout layout;
		layout.addSet(state);
		programHandle = program()->get(programKey);
		// Descriptors
		pool = graphic()->createDescriptorPool("DescriptorPool", state, 1);
		set = graphic()->allocateDescriptorSet("DescriptorSet", state, pool);
		gfx::DescriptorUpdate update = gfx::DescriptorUpdate::uniformBuffer(0, 0, ubo);
		graphic()->update(set, &update, 1);
		// Renderpass
		renderPass = graphic()->createBackbufferRenderPass();
		backbuffer = graphic()->createBackbuffer(renderPass);
		// Pipeline
		pipeline = graphic()->createGraphicPipeline(
			"GraphicPipeline",
			programHandle,
			gfx::PrimitiveType::Triangles,
			layout,
			graphic()->get(renderPass)->state,
			gfx::VertexState{}.add(vertexLayout),
			gfx::ViewportStateBackbuffer,
			gfx::DepthStateLessEqual,
			gfx::StencilStateDefault,
			gfx::CullStateCCW,
			gfx::BlendStateDefault,
			gfx::FillStateFill
		);
	}
	void onDestroy() override {
		graphic()->destroy(ubo);
		graphic()->destroy(vertexBuffer);
		graphic()->destroy(vertex);
		graphic()->destroy(fragment);
		graphic()->destroy(pipeline);
		graphic()->destroy(pool);
		graphic()->destroy(renderPass);
	}
	void onUpdate(Time deltaTime) override {
		rotation += anglef::radian(deltaTime.seconds());
	}
	void onRender(Renderer* _renderer, gfx::FrameHandle _frame) override {
		gfx::GraphicDevice* device = graphic();
		vec2f size = aka::vec2f(300.f);
		vec2f position = aka::vec2f(
			width() / 2.f - size.x / 2.f,
			height() / 2.f - size.y / 2.f
		);
		mat3f transform = aka::mat3f::identity();
		transform *= aka::mat3f::translate(position);
		transform *= aka::mat3f::translate(0.5f * size);
		transform *= aka::mat3f::rotate(rotation);
		transform *= aka::mat3f::translate(-0.5f * size);
		transform *= aka::mat3f::scale(size);

		UBO* data = static_cast<UBO*>(device->map(ubo, gfx::BufferMap::Write));
		data->model = mat4f::rotate(vec3f(0, 1, 0), rotation);// mat4f::from2D(transform);
		data->view = mat4f::lookAtView(point3f(3), point3f(0));
		data->projection = mat4f::perspective(anglef::degree(60.f), width() / (float)height(), 0.1f, 100.f);
		device->unmap(ubo);

		gfx::CommandList* cmd = device->getGraphicCommandList(_frame);
		//cmd->bindIndexBuffer(indexBuffer, gfx::IndexFormat::UnsignedInt);
		cmd->bindVertexBuffer(0, vertexBuffer);
		cmd->bindPipeline(pipeline);
		cmd->bindDescriptorSet(0, set);
		cmd->beginRenderPass(renderPass, device->get(backbuffer, _frame), gfx::ClearState{ gfx::ClearMask::All, {1.f, 1.f, 1.f, 1.f}, 1.f, 1 });
		cmd->draw(36, 0, 1);
		cmd->endRenderPass();
	}
	void onReceive(const KeyboardKeyDownEvent& event) override {
		if (event.key == KeyboardKey::Escape)
			EventDispatcher<QuitEvent>::emit();
	}
};
int main()
{
	aka::Config cfg;
	cfg.graphic.api = aka::gfx::GraphicAPI::Vulkan;
	cfg.platform.width = 1280;
	cfg.platform.height = 720;
	cfg.platform.name = "Game";
	Game game(cfg);
	aka::Application::run(&game);
	return 0;
}

Build

• Run --recursive with git clone or git submodule init / update to get all dependencies.
• Build using CMake. It has been tested on Windows (VS 2022) & Linux (GCC).

RoadMap

• Add DX12 support
• Some multithreading
• An editor
• Should probably go to Rust instead ?