activity.hpp File Reference

Descriptor for a piece of operational logic performed by the scheduler. More...

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Description

Descriptor for a piece of operational logic performed by the scheduler.

The Scheduler in Lumiera's Vault coordinates the rendering activities, by passing and responding to Activity messages, thereby observing temporal limits (deadlines) and dependency constraints. A predefined and fixed set of Activity verbs defines atomic operations the engine is able to perform, directed by the scheduler. Complex calculation tasks are constructed from interconnected activities, passed through the messaging and priority queue of the scheduler. While an Activity is in processing, the corresponding descriptor data record is maintained by the BlockStream custom memory manager.

Performing Activities

The Activity data records are »POD with constructor« and can be created and copied freely; the provided constructors ensure consistent setup, since the meaning of the variant data depends on the Activity::verb_. However, in actual usage, the builder functionality of the ActivityLang is used to generate linked »Activity terms«, connecting chains of Activities in accordance with an implicit execution protocol, which also forms the base of the Activity state machine:

• Activity::activate is invoked only once, when an Activity becomes active.
• the provided Execution Context is connected through several λ-bindings with the actual execution logic, as provided by »Layer-2« of the Scheduler
• Activity::dispatch is always invoked from within the scheduler and implies single threaded operation with the ability to mutate the scheduler queue; typically this happens after de-queuing an Activity from the priority queue and leads then to Activation of the retrieved Activity; however, it can also happen right away — when the indicated time has passed.
• Activity::INVOKE represents the relevant case of a »Render Job« and is typically performed by workers running concurrently
• Activity::notify receives a message/trigger from another prerequisite Activity

See also

SchedulerActivity_test

ActivityLang implementation of execution logic

Definition in file activity.hpp.

#include "vault/common.hpp"
#include "vault/gear/job.h"
#include "lib/time/timevalue.hpp"
#include "lib/meta/function.hpp"
#include "lib/util.hpp"

Namespaces
namespace	vault
	Vault-Layer implementation namespace root.
namespace	vault::gear
	Active working gear and plumbing.
namespace	vault::gear::activity

Enumerations
enum	Proc {   PASS ,   SKIP ,   WAIT ,   KICK ,   HALT }
	Result instruction from Activity activation. More...

Classes
class	ManifestationID
	Marker for current (and obsolete) manifestations of a CalcStream processed by the Render-Engine. More...
class	Instant
	< special definitions for the Scheduler activity language More...
class	Hook
	Extension point to invoke a callback from Activity activation. More...
class	Activity
	Record to describe an Activity, to happen within the Scheduler's control flow. More...
struct	Activity::Feed
	Payload data to provide. More...
struct	Activity::Timing
	Timing observation to propagate. More...
struct	Activity::Callback
	Extension point to invoke. More...
struct	Activity::Condition
	Access gate condition to evaluate. More...
struct	Activity::TimeWindow
	Time window to define for activation. More...
struct	Activity::Invocation
	External work functor to activate. More...
struct	Activity::Notification
	Notification towards another Activity. More...
union	Activity::ArgumentData
	Storage of Argument data dependent on Activity::verb_. More...

Functions
HashVal	hash_value (ManifestationID const &id)
template<class EXE >
constexpr void	_verify_usable_as_ExecutionContext ()
	Definition to emulate a Concept for the Execution Context.

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Class Documentation

vault::gear::Activity::Feed

struct vault::gear::Activity::Feed

Class Members
uint64_t	one
uint64_t	two

Collaboration diagram for Activity::Feed:

vault::gear::Activity::Timing

struct vault::gear::Activity::Timing

Class Members
Instant	instant
size_t	quality

Collaboration diagram for Activity::Timing:

vault::gear::Activity::Callback

struct vault::gear::Activity::Callback

Class Members
Hook *	hook
size_t	arg

Collaboration diagram for Activity::Callback:

vault::gear::Activity::TimeWindow

struct vault::gear::Activity::TimeWindow

Class Members
Instant	life
Instant	dead

Collaboration diagram for Activity::TimeWindow:

vault::gear::Activity::Invocation

struct vault::gear::Activity::Invocation

Class Members
JobFunctor *	task
Instant	time

Collaboration diagram for Activity::Invocation:

vault::gear::Activity::Notification

struct vault::gear::Activity::Notification

Class Members
Activity *	target
Instant	timing

Collaboration diagram for Activity::Notification:

vault::gear::Activity::ArgumentData

union vault::gear::Activity::ArgumentData

Class Members
Feed	feed
Timing	timing
Callback	callback
Condition	condition
TimeWindow	timeWindow
Invocation	invocation
Notification	notification

Collaboration diagram for Activity::ArgumentData: