Wizt::VRenderOptionUpdater< T > Struct Template Reference

When dealing with Render Anemones, it is frequent that the Anemone does not need to be re-created with each change of inputs. More...

#include <ocean/Anemonia/VRenderOptionUpdater.hpp>

Inheritance diagram for Wizt::VRenderOptionUpdater< T >:

Public Member Functions
bool	updateValue (VRenderContext &Context, RenderBasin::RenderParameter &RP) override
	Virtual update function that is called from Anemone::updateValues().
Public Member Functions inherited from MemCore::ReferenceBase< Updater >
auto	getObjectCountID () const noexcept
	Get a unique ID for this object in the given domain.
bool	isIdentical (const WeakPtr< Updater, Updater > &PossibleSelf) const noexcept
	Check if this object is identical to the one used by the given pointer.
void	mkAutoDestructive ()
	Marks this object as being automatically destructed, e.g.
refcount_t	refcount () const noexcept
	The strong reference count.
	ReferenceBase (Updater *that) noexcept
	Constructor, initializes reference counter to zero.
const auto &	self () const
	Return weak pointer to the object self.
refcount_t	wrefcount () const noexcept
	The weak reference count.

Additional Inherited Members
Public Types inherited from MemCore::ReferenceBase< Updater >
using	reference_domain_t = Updater
	The type of the base class.
using	SelfPtr_t = WeakPtr< Updater, Updater >
	Type for a pointer to this object itself.
Protected Member Functions inherited from MemCore::ReferenceBase< Updater >
virtual void	extremeUnction ()
	A virtual function that will be called just before the object is destroyed.
ReferenceBase &	operator= (const ReferenceBase &R)
	Protected assignment operator (should not be called).
void	suicide ()
	Delete this.
virtual	~ReferenceBase ()
	Virtual destructor.

Detailed Description

template<typename T>
struct Wizt::VRenderOptionUpdater< T >

When dealing with Render Anemones, it is frequent that the Anemone does not need to be re-created with each change of inputs.

Some input parameters only need to modify part of the render anemone, for instance a uniform parameter or a rendering flag. Class RenderBasin::RenderParameter::Updater provides a mechanism to ease this process.

Each render tentacle can be equipped with an updater object, which are child classes of RenderBasin::RenderParameter::Updater implementing the virtual member function

bool    updateValue(const WeakPtr<ValuePool>&Context, RenderBasin::RenderParameter&RP) override;

Such child classes will usually host a copy of the input slot and call the render parameter's modify() member function.

Class VRenderOptionUpdater allows to modify render parameter depending on whether some flag is set in the options or not. The type of these render parametes is flexible and specified as the template parameters, the value of these parameters and the name of te flag to be tested is given in the constructor.

The following code is an example how to read a flag from some options and to schedule modification of the render anemone (used in Heightfield.cpp and elsewhere):

VRenderObject class member definition:

in<Options>             tsOptions;

VRenderObject constructor:

, tsOptions(this, "options", Options("-wireframe") )

Code fragment in the render() function, provided an Anemone:

Anemone&RenderAnemone;
 
Options myOptions;
        tsOptions << Context >> myOptions;
 
RefPtr<RenderBasin::RenderParameter>
        PolygonMode = Context.createRenderParameter( "glPolygonMode", myOptions("wireframe")?1:2 );
 
        PolygonMode->myUpdater = new VRenderOptionUpdater<int>( tsOptions, "wireframe", 1, 2 );
 
        RenderAnemone.insert( PolygonMode );

Then, somewhere in the code elsewhere when an existing render anemone is retrieved and ready to be re-used, there needs to be a call to

RenderAnemone.updateValues(Context);