Freya¶

A Vulkan-based rendering engine powered by Skirnir for dependency injection.

Features¶

• Vulkan-backed rendering - Modern graphics API with high performance
• Deferred rendering - G-buffer path with SSAO, TAA, bloom, and HDR composite
• Composable frame stages - Insert or replace steps in Renderer::EndScene
• Feature flags - Toggle SSAO / TAA / Bloom and set shaderRoot via options
• Custom render targets - Offscreen composite via Renderer::SetViewportTarget / ClearOutputTarget, with opaque Vulkan/SDL handles (Renderer::GetImGuiNativeHandles, GetViewportImage) for hosting the scene in an application-level ImGui viewport; quality and vsync via FreyaOptions
• ImGui seam - Renderer::BeginUI / EndUI open the swapchain UI pass so apps draw Dear ImGui over an offscreen viewport without leaking vk::/SDL types into public headers
• Asset management - Meshes, textures (file or memory), and PBR materials
• Skinned animation - AnimGraph, bake, CPU or GPU skin palettes, LOD (see Animation)
• Event system - Flexible pub/sub event handling for window, keyboard, mouse, and gamepad
• Builder pattern - Fluent API plus FreyaExtension configure hooks
• Skirnir integration - IoC container for dependency injection

Headers¶

#include <Freya/Freya.hpp>    // app surface (no Vulkan / SDL types)

See API boundary and Flexibility.

Dependencies¶

• Vulkan SDK
• SDL3
• GLM
• Assimp (for 3D model loading)
• Skirnir (IoC Container)

Quick Start¶

#include <Freya/Freya.hpp>

class MainApp final : public fra::AbstractApplication
{
  public:
    explicit MainApp(const skr::Arc<skr::ServiceProvider>& serviceProvider)
        : AbstractApplication(serviceProvider)
    {
        mMeshPool     = serviceProvider->GetService<fra::MeshPool>();
        mTexturePool  = serviceProvider->GetService<fra::TexturePool>();
        mMaterialPool = serviceProvider->GetService<fra::MaterialPool>();
    }

    void StartUp() override
    {
        mRenderer->ClearProjections();
        // Initialize your assets here
    }

    void Update() override
    {
        mRenderer->BeginFrame();
        // Render your scene here
        mRenderer->EndFrame();
    }
};

int main(int argc, const char** argv)
{
    const auto app =
        skr::ApplicationBuilder()
            .WithExtension<fra::FreyaExtension>([](fra::FreyaExtension& freya) {
                freya.WithOptions([](fra::FreyaOptionsBuilder& freyaOptions) {
                    freyaOptions.SetTitle("My App")
                        .SetWidth(1920)
                        .SetHeight(1080)
                        .SetVSync(false)
                        .SetSampleCount(8);
                });
            })
            .Build<MainApp>();

    app->Run();
    return 0;
}

Project Structure¶

Freya/
├── include/Freya/      # Public headers (Freya.hpp, glm/Skirnir types)
├── src/Freya/          # .cpp + internal Vulkan headers + Vendor/
├── Examples/           # Example applications
├── Shaders/            # GLSL/Vulkan shaders
└── docs/               # Documentation

Configuration¶

Configure Freya using the FreyaOptionsBuilder:

freya.WithOptions([](fra::FreyaOptionsBuilder& freyaOptions) {
    freyaOptions.SetTitle("My Window")
        .SetWidth(1920)
        .SetHeight(1080)
        .SetVSync(true)
        .SetFullscreen(false)
        .SetSampleCount(4)
        .SetDrawDistance(1000.0f);
});

Available Options¶

Use SetShadowQuality / SetSsaoQuality / SetTaaQuality / SetBloomQuality (Low–Ultra) for presets; runtime mirrors on Renderer.

Use FreyaOptionsBuilder::SetShadowQuality(Low|Medium|High|Ultra) to set resolution, cascades, spot/point slots, and tap count together.

Services¶

Freya provides the following services via Skirnir's service provider: