Core API

Headers: src/core/engine.h, src/core/configuration.h
Namespace: glitter

`glitter::engine`

The root object of the engine. Handles its own complete initialisation — hardware layer, config loading, logging, renderer creation — in its constructor. main.cpp only creates it and calls run().

Subsystem accessors

Member	Returns	Description
`hwlayer()`	`HWLayer&`	Platform / windowing layer
`renderer()`	`Renderer&`	Active renderer (Vulkan)
`mainWindow()`	`Window&`	The primary SDL window
`resources()`	`glitter::resources&`	URI-based resource system
`renderContext()`	`RenderContext&`	Low-level GPU context (throws if not supported by the active renderer)
`shaders()`	`ShaderSystem&`	Shader loading and binding facade
`scene()`	`Scene&`	Scene object factory and cache
`sceneGraph()`	`SceneGraph&`	Live spatial scene graph
`loop()`	`LoopScheduler&`	Per-frame callback scheduler
`input()`	`InputMapper&`	Semantic input mapping (shortcut for `loop().inputMapper()`)
`postProcess()`	`IPostProcess&`	Active post-process pipeline (valid after `setupPostProcess()`)

Scene management

Member	Returns	Description
`loadScene(sceneUri)`	`LoadedScene`	Load a scene JSON, populate the scene graph, and apply ambient colour. Throws on failure.
`startupSceneUri()`	`std::string`	Returns `game.json["scenes"]["main"]`, or empty string if absent. Call after construction to locate the entry-point scene.

Post-processing

Member	Returns	Description
`setupPostProcess(shader)`	`IPostProcess&`	Create the offscreen framebuffer + screen-quad pipeline for the given tonemap shader. Must be called once before the first frame.

Configuration & paths

Member	Returns	Description
`registerPath(scheme, directory, readonly)`	`void`	Map a URI scheme to an absolute filesystem directory. `readonly` defaults to `true`.
`loadAndApplyConfiguration(uri)`	`void`	Load a config file by URI string and merge it with the current engine config.
`loadKeybinds()`	`void`	Load `res://keybinds.json` and apply the active keybind scheme to the input mapper.

Main loop

Member	Returns	Description
`run()`	`int`	Enter the main game loop. Returns `EXIT_SUCCESS` on clean shutdown. Dispatches events, then calls `onPreRender → onRender → onPostRender` each vsync frame.

Convenience helper

Defined in engine.h, usable without a full engine instance:

src/core/engine.h
std::shared_ptr<spdlog::logger> getLogger(const std::string& name)

Shortcut for glitter::logging::log_manager::get(name).

`glitter::engine_configuration`

Loaded from engine.config.json during engine construction. All fields have explicit defaults — no null checks are required by callers.

Top-level fields

Field	Type	Default	Description
`version`	`std::string`	`""`	Config schema version
`gameDir`	`std::string`	`""`	Directory containing `game.json` (resource paths)
`logging_level`	`spdlog::level::level_enum`	`warn`	Global log level for all loggers
`subsystem_levels`	`map<string, level_enum>`	`{}`	Per-subsystem log level overrides
`subsystem_sink_configs`	`map<string, json>`	`{}`	Per-subsystem sink configuration JSON
`log_file_path`	`std::string`	`"logs/glitter.log"`	Log file path relative to the executable

`renderer_config`

Field	Type	Default	Description
`use`	`std::string`	`"vulkan"`	Renderer name; looked up in `RendererRegistry`. Falls back to the default if unknown.
`antialias`	`bool`	`true`	Enable anti-aliasing (FXAA in post-process)

`window_config`

Field	Type	Default	Description
`width`	`int`	`800`	Initial window width in pixels
`height`	`int`	`600`	Initial window height in pixels
`resizable`	`bool`	`true`	Allow the window to be resized
`fullscreen`	`bool`	`false`	Start in fullscreen mode

`shadow_config`

Field	Type	Default	Description
`enabled`	`bool`	`true`	Enable directional cascade shadow maps
`pointShadowsEnabled`	`bool`	`true`	Enable omnidirectional point-light shadow cubemaps
`mapSize`	`int`	`2048`	Shadow map resolution (square, in pixels)
`cascadeCount`	`int`	`4`	Number of CSM cascades

`ssao_config`

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enable screen-space ambient occlusion
`kernelSize`	`int`	`64`	SSAO hemisphere sample count
`radius`	`float`	`0.5`	Sampling hemisphere radius in view space
`bias`	`float`	`0.025`	Self-occlusion bias

`ibl_config`

Field	Type	Default	Description
`enabled`	`bool`	`true`	Enable image-based lighting (irradiance map + pre-filtered specular + BRDF LUT)

`postprocess_config`

Field	Type	Default	Description
`exposure`	`float`	`1.0`	Tonemap exposure multiplier
`forwardPassEnabled`	`bool`	`true`	Render transparent / alpha-masked objects in a forward pass after deferred shading

`textures_config`

Field	Type	Default	Description
`maxAnisotropy`	`float`	`16.0`	Maximum anisotropic filtering level (1/2/4/8/16)
`mipLodBias`	`float`	`0.0`	MIP LOD bias — negative = sharper, positive = blurrier

`probes_config`

Field	Type	Default	Description
`skyBakeSize`	`int`	`512`	Sky environment probe cubemap resolution (128/256/512/1024)
`localBakeSize`	`int`	`128`	Local reflection probe cubemap resolution (64/128/256/512)

Free functions

Function	Returns	Description
`default_engine_configuration()`	`engine_configuration`	Construct a config with all fields at their defaults
`load_engine_configuration(res, uri)`	`engine_configuration`	Load from a JSON URI; throws on failure
`try_load_engine_configuration(res, uri)`	`expected<engine_configuration, string>`	Load from a JSON URI; returns an error string on failure
`merge_engine_configuration(defaults, overrides)`	`engine_configuration`	Merge two configs; fields present in `overrides` win
`apply_logging_configuration(cfg)`	`void`	Push log levels from a config into `log_manager`

glitter::engine​

Subsystem accessors​

Scene management​

Post-processing​

Configuration & paths​

Main loop​

Convenience helper​

glitter::engine_configuration​

Top-level fields​

renderer_config​

window_config​

shadow_config​

ssao_config​

ibl_config​

postprocess_config​

textures_config​

probes_config​

Free functions​