Builders¶

Freya uses the builder pattern to provide a fluent API for constructing engine components. Apps configure the engine with FreyaExtension::WithOptions. Vulkan device / swapchain / pass builders are internal (src/Freya/).

FreyaExtension hooks¶

.WithExtension<fra::FreyaExtension>([](fra::FreyaExtension& freya) {
    freya.WithOptions([](fra::FreyaOptionsBuilder& o) {
        o.SetTitle("My App")
         .SetShaderRoot("./Resources/Shaders")
         .SetEnableBloom(true);
    });
})

Shader SPIR-V paths are shaderRoot + "/DeferredCompressed|Shadow|Pick/…".

Overview¶

Public builders follow a consistent pattern:

auto component = SomeBuilder(params)
    .SetProperty1(value1)
    .SetProperty2(value2)
    .Build();

FreyaOptionsBuilder¶

Configures engine options.

freya.WithOptions([](fra::FreyaOptionsBuilder& freyaOptions) {
    freyaOptions.SetTitle("My App")
        .SetWidth(1920)
        .SetHeight(1080)
        .SetVSync(false)
        .SetSampleCount(8)
        .SetFullscreen(false)
        .SetDrawDistance(1000.0f)
        .SetShadowQuality(fra::ShadowQuality::Medium);
});

SetShadowQuality applies Low / Medium / High / Ultra budgets for shadow map resolution, cascade count, spot/point slots, and soft-shadow tap count. Individual setters can still override fields after the preset.

PostProcessBuilder¶

Builds a post-deferred fullscreen pass. Obtain it from the service provider and insert the stage before Bloom:

struct CellPushConstants { /* match your .frag push_constant */ };

auto cell = serviceProvider->GetService<fra::PostProcessBuilder>()
                ->SetName("Cell")
                .SetFragment("Cell/cell.frag.spv")
                .SetInputs({ fra::PostProcessInput::SceneColor,
                             fra::PostProcessInput::Depth,
                             fra::PostProcessInput::Normal })
                .SetPushConstantSize(sizeof(CellPushConstants))
                .Build();

mRenderer->InsertFrameStage("Bloom", cell->MakeStage());

See Flexibility.