OSDL: OSDL::Rendering::Renderer Class Reference

Note that renderers and views are not dedicated to the graphical output, since they have to take in charge all multimedia fields, including sounds and, possibly, other media.

The privilegied way of organizing the rendering is to have renderers taking care of all its aspects (video, but also audio, etc.).

Renderers are not necessarily singletons, but having only one centralized instance for all views might be simpler. In this case it is called a root renderer. A root renderer may delegate part of its task to specialized sub-renderers.

More precisely, the scheduler will call only one of them, the root renderer, which may delegate a part of its charge to any number of specialized renderers, for example if multiple viewports are used in the same window, or for the sound, or to take advantage of multicore processors.

A renderer knows all the views (as defined by the MVC framework) it is in charge of, but only them (not their model for instance).

However no data structure is provided with this generic renderer, $ since it may vary a lot depending on the need, from simple list to BSP trees, etc.

Definition at line 84 of file OSDLRenderer.h.


Public Member Functions
	Renderer (bool registerToScheduler=true) throw ( RenderingException )
	Constructs a new renderer.
virtual	~Renderer () throw ()
	Virtual destructor, no view is destroyed.
virtual void	render (Events::RenderingTick currentRenderingTick=0) throw ()
	Triggers the actual rendering of all views, for specified rendering tick, if any.
virtual void	onRenderingSkipped (Events::RenderingTick skippedRenderingTick) throw ()
	Allows the renderer to be aware that a rendering step has to be skipped.
virtual const std::string	toString (Ceylan::VerbosityLevels level=Ceylan::high) const throw ()
	Returns an user-friendly description of the state of this object.
Static Public Member Functions
static bool	HasExistingRootRenderer () throw ()
	Tells whether a root renderer is available.
static Renderer &	GetExistingRootRenderer () throw ( RenderingException )
	Returns the one and only one root renderer instance that may be already available.
static void	DeleteExistingRootRenderer () throw ( RenderingException )
	Deletes the existing root renderer.
static void	DeleteRootRenderer () throw ()
	Deletes the root renderer, if any.
Protected Attributes
RenderCount	_renderingDone
	Counts the number of renderings achieved.
RenderCount	_renderingSkipped
	Counts the number of renderings skipped.
Events::RenderingTick	_lastRender
	Records the last rendering tick.
Private Member Functions
	Renderer (const Renderer &source) throw ()
	Copy constructor made private to ensure that it will never be called.
Renderer &	operator= (const Renderer &source) throw ()
	Assignment operator made private to ensure that it will never be called.
Static Private Attributes
static Renderer *	_internalRootRenderer
	The internal single instance of renderer, at the top of the renderer hierarchy, if any.

Constructor & Destructor Documentation

Renderer::Renderer ( bool registerToScheduler = true ) throw ( RenderingException ) [explicit]

Constructs a new renderer.

Parameters:

registerToScheduler

iff true, then a scheduler is supposed to exist already, and this renderer is automatically registered to this scheduler so that it gets called at each rendering tick.

Exceptions:

RenderingException

if registerToScheduler is true and no scheduler is available.

Definition at line 48 of file OSDLRenderer.cc.

Renderer::~Renderer ( ) throw () [virtual]

Virtual destructor, no view is destroyed.

Definition at line 72 of file OSDLRenderer.cc.

OSDL::Rendering::Renderer::Renderer ( const Renderer & source ) throw () [explicit, private]

Copy constructor made private to ensure that it will never be called.

The compiler should complain whenever this undefined constructor is called, implicitly or not.

Member Function Documentation

void Renderer::render ( Events::RenderingTick currentRenderingTick = 0 ) throw () [virtual]

Triggers the actual rendering of all views, for specified rendering tick, if any.

Parameters:

currentRenderingTick

the rendering tick corresponding to this render step. If the renderer is called from a basic event loop (no scheduler is used), then the rendering tick is meaningless and is always zero.

Reimplemented in OSDL::Rendering::AudioRenderer, OSDL::Rendering::MultimediaRenderer, and OSDL::Rendering::VideoRenderer.

Definition at line 80 of file OSDLRenderer.cc.

References OSDL_RENDER_LOG.

void Renderer::onRenderingSkipped ( Events::RenderingTick skippedRenderingTick ) throw () [virtual]

Allows the renderer to be aware that a rendering step has to be skipped.

It may be a chance for it to trigger counter-measures, such as decreasing the level of detail in order not to slow down the whole process.

Parameters:

skippedRenderingTick

the rendering tick that had to be skipped.

Reimplemented in OSDL::Rendering::AudioRenderer, OSDL::Rendering::MultimediaRenderer, and OSDL::Rendering::VideoRenderer.

Definition at line 95 of file OSDLRenderer.cc.

References OSDL_RENDER_LOG.

const string Renderer::toString ( Ceylan::VerbosityLevels level = Ceylan::high ) const throw () [virtual]

Returns an user-friendly description of the state of this object.

Parameters:

level

the requested verbosity level.

Note:: Text output format is determined from overall settings.

See also:: Ceylan::TextDisplayable

Reimplemented in OSDL::Rendering::AudioRenderer, OSDL::Rendering::MultimediaRenderer, and OSDL::Rendering::VideoRenderer.

Definition at line 104 of file OSDLRenderer.cc.

References OSDL::Video::Pixels::toString().

Referenced by OSDL::Engine::Scheduler::schedule().

bool Renderer::HasExistingRootRenderer ( ) throw () [static]

Tells whether a root renderer is available.

Returns:: true iff a root renderer is already available.

Definition at line 123 of file OSDLRenderer.cc.

References _internalRootRenderer.

Referenced by OSDL::Events::EventsModule::enterBasicMainLoop().

Renderer & Renderer::GetExistingRootRenderer ( ) throw ( RenderingException ) [static]

Returns the one and only one root renderer instance that may be already available.

Note:: The returned value is a reference and not a pointer, to avoid any abnormal deallocation by its users, that should never deallocate the root renderer.

Exceptions:

RenderingException

if there is no root renderer already available.

Note:: There is no 'GetRootRenderer' method that would create a root renderer if none was already set, since various renderers could be chosen as the root one.

Definition at line 131 of file OSDLRenderer.cc.

References _internalRootRenderer.

Referenced by OSDL::Events::EventsModule::enterBasicMainLoop().

void Renderer::DeleteExistingRootRenderer ( ) throw ( RenderingException ) [static]

Deletes the existing root renderer.

Exceptions:

RenderingException

if not renderer was available.

Definition at line 142 of file OSDLRenderer.cc.

References _internalRootRenderer.

void Renderer::DeleteRootRenderer ( ) throw () [static]

Deletes the root renderer, if any.