Scarab::Host::EngineHost Class Reference

Scarab's own game engine: the state machine (init/ run-stage/fatal-error handlers), the ScriptProcessor/LuaEngine wiring, and the small amount of per-frame bookkeeping (BGM looping, sp_wait_queue_empty resolution) that isn't Lua's job. Used to be split across WorldBase (a reusable base class) and WorldEngine (Scarab's state machine subclassing it) - merged since nothing else ever subclassed WorldBase and the split no longer served polymorphism, just indirection. Renamed from WorldEngine/Caravellius::World once the Lua refactor left it owning no "world" state at all (no tile map pointer, no sprite queues, no camera) - it's a lifecycle/Lua-bridge host, not a world model. More...

#include <enginehost.h>

Inheritance diagram for Scarab::Host::EngineHost:

Collaboration diagram for Scarab::Host::EngineHost:

Public Member Functions
	EngineHost (Scarab ::Host ::RendererProvider *pRendererProvider, std ::string strEntryArg, std ::string strEntryOverride=std ::string())
virtual	~EngineHost (void)
void	RunEntryScript (void)
	Run the entry script (main.lua, or whatever the entry argument resolves to) - BEFORE the window exists, called by main() ahead of the frame loop. The script may create the renderer itself (renderer_create); anything that needs a window before it has done so creates the default renderer on the spot (see RendererProvider), and a script that never needs one gets the default when it finishes, so the loop always has a renderer to run on.
void	UseVirtualTime (void)
	Headless (–headless) only - make Lua's os.time()/ os.clock() follow the null renderer's virtual clock. Called by main() right after construction, before Start() (so before any Lua script has run); a no-op for a real-window run, which never calls it.
void	OnUpdate (SunLight ::TileMap ::ITileMap &tileMap)
void	OnStop (void)
	Perform world listener cleaning before world window closing. Runs while TileMapRenderer's window/GL context is still alive (see TileMapRenderer::Stop(), which calls every listener's OnStop() before CloseWindow()) - releasing the sprite pool's textures here, rather than leaving it to ~SpritePool() at program exit, avoids unloading GPU textures after the context is already gone.
void	OnCommand (SunLight ::Scripting ::Commands cmd, uint16_t nEventId)
	Must be implemented to respond STOP_SONG_CMD command;.
void	OnError (std ::string strError)
	Runtime error handling.

Detailed Description

Scarab's own game engine: the state machine (init/ run-stage/fatal-error handlers), the ScriptProcessor/LuaEngine wiring, and the small amount of per-frame bookkeeping (BGM looping, sp_wait_queue_empty resolution) that isn't Lua's job. Used to be split across WorldBase (a reusable base class) and WorldEngine (Scarab's state machine subclassing it) - merged since nothing else ever subclassed WorldBase and the split no longer served polymorphism, just indirection. Renamed from WorldEngine/Caravellius::World once the Lua refactor left it owning no "world" state at all (no tile map pointer, no sprite queues, no camera) - it's a lifecycle/Lua-bridge host, not a world model.

Constructor & Destructor Documentation

EngineHost()

Scarab::Host::EngineHost::EngineHost	(	Scarab ::Host ::RendererProvider *	pRendererProvider,
		std ::string	strEntryArg,
		std ::string	strEntryOverride = std :: string()
	)

Constructor. Initialize all class data.

Parameters

pRendererProvider	The provider the renderer is created through (lazily - it does not exist yet); this registers itself as the tile-map listener of whatever renderer it creates;
strEntryArg	The entry argument main.cpp requires on the command line (a .lua script path or a .json project file) - resolved later, from RunEntryScript, since a failure there already has a normal fatal-error path to report through.

~EngineHost()

Scarab::Host::EngineHost::~EngineHost ( void  )

virtual

Destructor. Finalize all class data.

Member Function Documentation

OnCommand()

void Scarab::Host::EngineHost::OnCommand	(	SunLight ::Scripting ::Commands	cmd,
		uint16_t	nEventId
	)

Must be implemented to respond STOP_SONG_CMD command;.

Parameters

cmd	The command received/
nEventId	The event id;

OnError()

void Scarab::Host::EngineHost::OnError

(

std ::string

strError

)

Runtime error handling.

Parameters

strError

The engine error message received;

OnStop()

void Scarab::Host::EngineHost::OnStop

(

void

)

Perform world listener cleaning before world window closing. Runs while TileMapRenderer's window/GL context is still alive (see TileMapRenderer::Stop(), which calls every listener's OnStop() before CloseWindow()) - releasing the sprite pool's textures here, rather than leaving it to ~SpritePool() at program exit, avoids unloading GPU textures after the context is already gone.

OnUpdate()

void Scarab::Host::EngineHost::OnUpdate

(

SunLight ::TileMap ::ITileMap &

tileMap

)

Provide action on each frame update.

Parameters

tileMap

The object used to interact with tile map renderer implementation;

RunEntryScript()

void Scarab::Host::EngineHost::RunEntryScript

(

void

)

Run the entry script (main.lua, or whatever the entry argument resolves to) - BEFORE the window exists, called by main() ahead of the frame loop. The script may create the renderer itself (renderer_create); anything that needs a window before it has done so creates the default renderer on the spot (see RendererProvider), and a script that never needs one gets the default when it finishes, so the loop always has a renderer to run on.

A failure is a normal fatal error: reported and the process exits, exactly as it used to from the first frame of the loop - just without a window having flashed open first.

UseVirtualTime()

void Scarab::Host::EngineHost::UseVirtualTime

(

void

)

Headless (–headless) only - make Lua's os.time()/ os.clock() follow the null renderer's virtual clock. Called by main() right after construction, before Start() (so before any Lua script has run); a no-op for a real-window run, which never calls it.

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The documentation for this class was generated from the following files:

• src/host/enginehost.h
• src/host/enginehost.cpp