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AsyncTask Class Reference

This class represents a concrete task performed by an AsyncManager. More...

#include "asyncTask.h"

Inheritance diagram for AsyncTask:
AsyncFuture Namable TypedReferenceCount MemoryBase TypedObject ReferenceCount MemoryBase MemoryBase AnimateVerticesRequest AsyncTaskPause AsyncTaskSequence AudioLoadRequest GenericAsyncTask ModelFlattenRequest ModelLoadRequest ModelSaveRequest TextureReloadRequest

Public Types

enum  DoneStatus {
  DS_done, DS_cont, DS_again, DS_pickup,
  DS_exit, DS_pause, DS_interrupt, DS_await
}
 
enum  State {
  S_inactive, S_active, S_servicing, S_servicing_removed,
  S_sleeping, S_active_nested, S_awaiting
}
 
- Public Types inherited from AsyncFuture
typedef pvector< PT(AsyncFuture)> Futures
 

Public Member Functions

 AsyncTask (const std::string &name=std::string())
 
void clear_delay ()
 Removes any delay specified for the task. More...
 
void clear_name ()
 Resets the task's name to empty. More...
 
virtual TypeHandle force_init_type ()
 
double get_average_dt () const
 
double get_delay () const
 Returns the delay value that has been set via set_delay, if any. More...
 
double get_dt () const
 
int get_elapsed_frames () const
 Returns the number of frames that have elapsed since the task was started, according to the task manager's clock. More...
 
double get_elapsed_time () const
 Returns the amount of time that has elapsed since the task was started, according to the task manager's clock. More...
 
AsyncTaskManagerget_manager () const
 
double get_max_dt () const
 
std::string get_name_prefix () const
 Returns the initial part of the name, up to but not including any trailing digits following a hyphen or underscore. More...
 
int get_priority () const
 
int get_sort () const
 
int get_start_frame () const
 Returns the frame number at which the task was started, according to the task manager's clock. More...
 
double get_start_time () const
 Returns the time at which the task was started, according to the task manager's clock. More...
 
State get_state () const
 
const std::string & get_task_chain () const
 
AtomicAdjust::Integer get_task_id () const
 
virtual TypeHandle get_type () const
 
double get_wake_time () const
 If this task has been added to an AsyncTaskManager with a delay in effect, this returns the time at which the task is expected to awaken. More...
 
bool has_delay () const
 Returns true if a delay has been set for this task via set_delay(), or false otherwise. More...
 
bool is_alive () const
 
virtual void output (std::ostream &out) const
 
void recalc_wake_time ()
 If the task is currently sleeping on a task chain, this resets its wake time to the current time + get_delay(). More...
 
bool remove ()
 Removes the task from its active manager, if any, and makes the state S_inactive (or possible S_servicing_removed). More...
 
void set_delay (double delay)
 Specifies the amount of time, in seconds, by which this task will be delayed after it has been added to the AsyncTaskManager. More...
 
void set_done_event (const std::string &done_event)
 
void set_name (const std::string &name)
 
void set_priority (int priority)
 
void set_sort (int sort)
 
void set_task_chain (const std::string &chain_name)
 
- Public Member Functions inherited from AsyncFuture
 AsyncFuture ()
 Initializes the future in the pending state. More...
 
virtual ~AsyncFuture ()
 Destroys the future. More...
 
bool add_waiting_task (AsyncTask *task)
 Indicates that the given task is waiting for this future to complete. More...
 
bool cancelled () const
 Returns true if the future was cancelled. More...
 
bool done () const
 Returns true if the future is done or has been cancelled. More...
 
const std::string & get_done_event () const
 
TypedObjectget_result () const
 Returns this future's result. More...
 
void get_result (TypedObject *&ptr, ReferenceCount *&ref_ptr) const
 Returns this future's result as a pair of TypedObject, ReferenceCount pointers. More...
 
void notify_done (bool clean_exit)
 Schedules the done callbacks. More...
 
void set_done_event (const std::string &done_event)
 
void set_result (std::nullptr_t)
 Sets this future's result. More...
 
void set_result (TypedObject *result)
 
void set_result (TypedReferenceCount *result)
 
void set_result (TypedWritableReferenceCount *result)
 
void set_result (const EventParameter &result)
 
void set_result (TypedObject *ptr, ReferenceCount *ref_ptr)
 Sets this future's result. More...
 
void wait ()
 Waits until the future is done. More...
 
void wait (double timeout)
 Waits until the future is done, or until the timeout is reached. More...
 
- Public Member Functions inherited from TypedReferenceCount
 TypedReferenceCount (const TypedReferenceCount &copy)
 
void operator= (const TypedReferenceCount &copy)
 
- Public Member Functions inherited from TypedObject
 TypedObject (const TypedObject &copy)=default
 
TypedObjectas_typed_object ()
 Returns the object, upcast (if necessary) to a TypedObject pointer. More...
 
const TypedObjectas_typed_object () const
 Returns the object, upcast (if necessary) to a TypedObject pointer. More...
 
int get_best_parent_from_Set (const std::set< int > &) const
 
int get_type_index () const
 Returns the internal index number associated with this object's TypeHandle, a unique number for each different type. More...
 
bool is_exact_type (TypeHandle handle) const
 Returns true if the current object is the indicated type exactly. More...
 
bool is_of_type (TypeHandle handle) const
 Returns true if the current object is or derives from the indicated type. More...
 
TypedObjectoperator= (const TypedObject &copy)=default
 
- Public Member Functions inherited from ReferenceCount
int get_ref_count () const
 
WeakReferenceListget_weak_list () const
 Returns the WeakReferenceList associated with this ReferenceCount object. More...
 
bool has_weak_list () const
 Returns true if this particular ReferenceCount object has a WeakReferenceList created, false otherwise. More...
 
void local_object ()
 This function should be called, once, immediately after creating a new instance of some ReferenceCount-derived object on the stack. More...
 
void ref () const
 Explicitly increments the reference count. More...
 
bool ref_if_nonzero () const
 Atomically increases the reference count of this object if it is not zero. More...
 
bool test_ref_count_integrity () const
 Does some easy checks to make sure that the reference count isn't completely bogus. More...
 
bool test_ref_count_nonzero () const
 Does some easy checks to make sure that the reference count isn't zero, or completely bogus. More...
 
virtual bool unref () const
 Explicitly decrements the reference count. More...
 
WeakReferenceListweak_ref ()
 Adds the indicated PointerToVoid as a weak reference to this object. More...
 
void weak_unref ()
 Removes the indicated PointerToVoid as a weak reference to this object. More...
 
- Public Member Functions inherited from Namable
 Namable (const std::string &initial_name="")
 
void clear_name ()
 Resets the Namable's name to empty. More...
 
const std::string & get_name () const
 
bool has_name () const
 Returns true if the Namable has a nonempty name set, false if the name is empty. More...
 
void output (std::ostream &out) const
 Outputs the Namable. More...
 
void set_name (const std::string &name)
 

Static Public Member Functions

static TypeHandle get_class_type ()
 
static void init_type ()
 
- Static Public Member Functions inherited from AsyncFuture
static AsyncFuturegather (Futures futures)
 Creates a new future that returns `done()` when all of the contained futures are done. More...
 
static TypeHandle get_class_type ()
 
static void init_type ()
 
- Static Public Member Functions inherited from TypedReferenceCount
static TypeHandle get_class_type ()
 
static void init_type ()
 
- Static Public Member Functions inherited from TypedObject
static TypeHandle get_class_type ()
 
static void init_type ()
 This function is declared non-inline to work around a compiler bug in g++ 2.96. More...
 
- Static Public Member Functions inherited from ReferenceCount
static TypeHandle get_class_type ()
 
static void init_type ()
 
- Static Public Member Functions inherited from Namable
static TypeHandle get_class_type ()
 
static void init_type ()
 

Public Attributes

 get_average_dt
 Returns the average amount of time elapsed during each of the task's previous run cycles, in seconds. More...
 
 get_done_event
 
 get_dt
 Returns the amount of time elapsed during the task's previous run cycle, in seconds. More...
 
 get_manager
 Returns the AsyncTaskManager that this task is active on. More...
 
 get_max_dt
 Returns the maximum amount of time elapsed during any one of the task's previous run cycles, in seconds. More...
 
 get_name
 
 get_priority
 Returns the task's current priority value. More...
 
 get_sort
 Returns the task's current sort value. More...
 
 get_state
 Returns the current state of the task. More...
 
 get_task_chain
 Returns the AsyncTaskChain on which this task will be running. More...
 
 get_task_id
 Returns a number guaranteed to be unique for each different AsyncTask object in the universe. More...
 
 is_alive
 Returns true if the task is currently active or sleeping on some task chain, meaning that it will be executed in its turn, or false if it is not active. More...
 
 set_done_event
 Sets the event name that will be triggered when the task finishes. More...
 
 set_name
 
 set_priority
 Specifies a priority value for this task. More...
 
 set_sort
 Specifies a sort value for this task. More...
 
 set_task_chain
 Specifies the AsyncTaskChain on which this task will be running. More...
 
- Public Attributes inherited from AsyncFuture
 get_done_event
 Returns the event name that will be triggered when the future finishes. More...
 
 set_done_event
 Sets the event name that will be triggered when the future finishes. More...
 
- Public Attributes inherited from TypedObject
 get_type
 
- Public Attributes inherited from ReferenceCount
 get_ref_count
 Returns the current reference count. More...
 
- Public Attributes inherited from Namable
 get_name
 
 set_name
 

Friends

class AsyncFuture
 
class AsyncTaskChain
 
class AsyncTaskManager
 
class AsyncTaskSequence
 
class PythonTask
 

Detailed Description

This class represents a concrete task performed by an AsyncManager.

Normally, you would subclass from this class, and override do_task(), to define the functionality you wish to have the task perform.

Definition at line 32 of file asyncTask.h.

Member Function Documentation

◆ clear_delay()

void AsyncTask::clear_delay ( )
inline

Removes any delay specified for the task.

The next time the task is added to the queue, it will run immediately. This does not affect the task's wake time if it has already been added to the queue.

Definition at line 83 of file asyncTask.I.

◆ clear_name()

void AsyncTask::clear_name ( )
inline

Resets the task's name to empty.

Definition at line 133 of file asyncTask.I.

◆ get_delay()

double AsyncTask::get_delay ( ) const
inline

Returns the delay value that has been set via set_delay, if any.

Definition at line 101 of file asyncTask.I.

◆ get_elapsed_frames()

int AsyncTask::get_elapsed_frames ( ) const

Returns the number of frames that have elapsed since the task was started, according to the task manager's clock.

It is only valid to call this if the task's status is not S_inactive.

Definition at line 160 of file asyncTask.cxx.

◆ get_elapsed_time()

double AsyncTask::get_elapsed_time ( ) const

Returns the amount of time that has elapsed since the task was started, according to the task manager's clock.

It is only valid to call this if the task's status is not S_inactive.

Definition at line 147 of file asyncTask.cxx.

◆ get_name_prefix()

string AsyncTask::get_name_prefix ( ) const

Returns the initial part of the name, up to but not including any trailing digits following a hyphen or underscore.

Definition at line 225 of file asyncTask.cxx.

◆ get_start_frame()

int AsyncTask::get_start_frame ( ) const
inline

Returns the frame number at which the task was started, according to the task manager's clock.

It is only valid to call this if the task's status is not S_inactive.

Definition at line 124 of file asyncTask.I.

◆ get_start_time()

double AsyncTask::get_start_time ( ) const
inline

Returns the time at which the task was started, according to the task manager's clock.

It is only valid to call this if the task's status is not S_inactive.

Definition at line 112 of file asyncTask.I.

◆ get_wake_time()

double AsyncTask::get_wake_time ( ) const

If this task has been added to an AsyncTaskManager with a delay in effect, this returns the time at which the task is expected to awaken.

It has no meaning if the task has not yet been added to a queue, or if there was no delay in effect at the time the task was added.

If the task's status is not S_sleeping, this returns 0.0.

Definition at line 104 of file asyncTask.cxx.

◆ has_delay()

bool AsyncTask::has_delay ( ) const
inline

Returns true if a delay has been set for this task via set_delay(), or false otherwise.

Definition at line 93 of file asyncTask.I.

◆ recalc_wake_time()

void AsyncTask::recalc_wake_time ( )

If the task is currently sleeping on a task chain, this resets its wake time to the current time + get_delay().

It is as if the task had suddenly returned DS_again. The task will sleep for its current delay seconds before running again. This method may therefore be used to make the task wake up sooner or later than it would have otherwise.

If the task is not already sleeping, this method has no effect.

Definition at line 126 of file asyncTask.cxx.

◆ remove()

bool AsyncTask::remove ( )

Removes the task from its active manager, if any, and makes the state S_inactive (or possible S_servicing_removed).

This is a no-op if the state is already S_inactive.

Definition at line 73 of file asyncTask.cxx.

Referenced by AsyncTaskManager::remove().

◆ set_delay()

void AsyncTask::set_delay ( double  delay)
inline

Specifies the amount of time, in seconds, by which this task will be delayed after it has been added to the AsyncTaskManager.

At least the specified amount of time (and possibly more) will elapse before the task begins.

You may specify a delay of 0.0 to guarantee that the task will run in the next epoch following the one in which it is added.

Setting this value after the task has already been added will not affect the task's wake time; it will only affect the task if it is re-added to the queue in the future, for instance if the task returns DS_again. However, see recalc_wake_time() if you wish to apply the delay effect immediately.

Definition at line 72 of file asyncTask.I.

Member Data Documentation

◆ get_average_dt

double AsyncTask::get_average_dt
inline

Returns the average amount of time elapsed during each of the task's previous run cycles, in seconds.

Definition at line 121 of file asyncTask.h.

◆ get_dt

double AsyncTask::get_dt
inline

Returns the amount of time elapsed during the task's previous run cycle, in seconds.

Definition at line 119 of file asyncTask.h.

◆ get_manager

AsyncTaskManager * AsyncTask::get_manager
inline

Returns the AsyncTaskManager that this task is active on.

This will be NULL if the state is S_inactive.

Definition at line 105 of file asyncTask.h.

◆ get_max_dt

double AsyncTask::get_max_dt
inline

Returns the maximum amount of time elapsed during any one of the task's previous run cycles, in seconds.

Definition at line 120 of file asyncTask.h.

◆ get_priority

int AsyncTask::get_priority
inline

Returns the task's current priority value.

See set_priority().

Definition at line 116 of file asyncTask.h.

◆ get_sort

int AsyncTask::get_sort
inline

Returns the task's current sort value.

See set_sort().

Definition at line 115 of file asyncTask.h.

◆ get_state

AsyncTask::State AsyncTask::get_state
inline

Returns the current state of the task.

Definition at line 103 of file asyncTask.h.

◆ get_task_chain

const std::string & AsyncTask::get_task_chain
inline

Returns the AsyncTaskChain on which this task will be running.

Each task chain runs tasks independently of the others.

Definition at line 114 of file asyncTask.h.

◆ get_task_id

AtomicAdjust::Integer AsyncTask::get_task_id
inline

Returns a number guaranteed to be unique for each different AsyncTask object in the universe.

Definition at line 112 of file asyncTask.h.

◆ is_alive

bool AsyncTask::is_alive
inline

Returns true if the task is currently active or sleeping on some task chain, meaning that it will be executed in its turn, or false if it is not active.

If the task has recently been removed while it is in the middle of execution, this will return false, because the task will not run again once it finishes.

Definition at line 104 of file asyncTask.h.

◆ set_done_event

void AsyncTask::set_done_event
inline

Sets the event name that will be triggered when the task finishes.

This should only be called before the task has been started, or after it has finished and before it is about to be restarted (i.e. when get_state() returns S_inactive).

Definition at line 117 of file asyncTask.h.

◆ set_priority

void AsyncTask::set_priority

Specifies a priority value for this task.

In general, tasks with a higher priority value are executed before tasks with a lower priority value (but only for tasks with the same sort value).

Unlike the sort value, tasks with different priorities may execute at the same time, if the AsyncTaskManager has more than one thread servicing tasks.

Also see AsyncTaskChain::set_timeslice_priority(), which changes the meaning of this value. In the default mode, when the timeslice_priority flag is false, all tasks always run once per epoch, regardless of their priority values (that is, the priority controls the order of the task execution only, not the number of times it runs). On the other hand, if you set the timeslice_priority flag to true, then changing a task's priority has an effect on the number of times it runs.

Definition at line 116 of file asyncTask.h.

◆ set_sort

void AsyncTask::set_sort

Specifies a sort value for this task.

Within a given AsyncTaskManager, all of the tasks with a given sort value are guaranteed to be completed before any tasks with a higher sort value are begun.

To put it another way, two tasks might execute in parallel with each other only if they both have the same sort value. Tasks with a lower sort value are executed first.

This is different from the priority, which makes no such exclusion guarantees.

Definition at line 115 of file asyncTask.h.

◆ set_task_chain

void AsyncTask::set_task_chain

Specifies the AsyncTaskChain on which this task will be running.

Each task chain runs tasks independently of the others.

Definition at line 114 of file asyncTask.h.

Referenced by Loader::save_async().


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