arclightengine/arclightengine

Arclight Engine

A lightweight 2D game engine written in C++20 using Vulkan and SDL.

Features:

• Multithreaded
• Unicode support
• Supports Vulkan and WebGL
• ECS architecture

Platforms:

• Linux
• WebAssembly/Emscripten
• Windows

Future goals:

• Clean API
• Multi-language/Scripting support
• Heavily multithreaded
• Networking support
• Multiplatform support (Windows, macOS, FreeBSD, Android?)

Building The Engine

Requirements:

• CMake
• Ninja (optional, highly recommended)

Native build:

• SDL2
• ICU
• Freetype
• Vulkan SDK

WebAssembly build:

• Emscripten

Linux

Host Build

cmake -B Build -G Ninja -DUSE_VULKAN=ON
ninja -C Build

WASM/Emscripten Build

cmake -B Build/wasm -G Ninja -DUSE_OPENGL=ON
ninja -C Build/wasm

Building The Examples

Host Build

./arclight-build.py --dir Examples/Ball build
./arclight-build.py --dir Examples/Ball run

WASM/Emscripten Build

./arclight-build.py --platform wasm --dir Examples/Ball build
./arclight-build.py --platform wasm --dir Examples/Ball run

Third Party

Arclight engine uses the following third party libraries:

• SDL2
• AMD's Vulkan Memory Allocator
• stb_image
• nlohmann/json
• Freetype
• ICU
• EnTT
• libfmt

arclightengine's Issues

Improve Sprite creation and usage

At the moment sprite creation is not very clean. To create a sprite, pixel dimensions and texture coordinates should be taken in. A function should be provided to convert from a Rect using pixel offsets to texture coordinates.

Emscripten/WebAssembly Target

Have Arclight compile using emscripten to WASM.

More configurable system execution

Systems should be able to run on multiple states, run once at the start of a state and run only after other systems have ran.

VulkanRenderer can only draw on a single thread

Should have a per-thread command buffer.

Finish implementing text rendering

Text rendering is not finished, neither is Font handling. 2DRenderer should be extended to render text objects.

Cleaner Application interface

Currently the Application class is a bit cumbersome and not very intuitive.

Considering using a builder pattern to allow initialization of systems. Furthermore, init systems and systems as only functions may allow easier use of systems, especially for smaller games that don't need a full class for systems.

Also limit the use of Application as a singleton, potentially passing the World object to the system.

Implement WebGL support

This is a step in getting ArclightEngine to run on the web. WebGL currently has wider support than WebGPU.

Rendering: Reduce draw calls and texture binds

Make use of indirect drawing in Vulkan and OpenGL to reduce the amount of draw calls. In the shaders considering using an array of transforms to allow the shader to access multiple transforms.

In reducing texture binds I am considering using the reactive functionality of EnTT to track Sprite component updates and grouping sprites by texture. Texture arrays could also be employed.