Task: Difference between revisions

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#redirect [[Creating a task]]
{{npc tut}}
 
A '''Task''' is an action that an NPC can perform. [[Schedule]]s will run a list of tasks. Keep tasks as atomic as possible; don't squeeze two distinct actions into the same one.
 
== Creating a task ==
 
Custom tasks are added by first declaring a new enum value.
 
<source lang=cpp>
enum
{
TASK_JUMP = LAST_SHARED_TASK,
TASK_FIND_DODGE_DIRECTION,
LAST_MY_NPC_TASK,
};
</source>
 
After that, the task itself should be declared like this:
 
<source lang=cpp>
AI_BEGIN_CUSTOM_NPC( npc_custom, CNPC_Custom )
DECLARE_TASK( TASK_FIND_DODGE_DIRECTION )
AI_END_CUSTOM_SCHEDULE_PROVIDER()
</source>
 
Then you add the tasks in your custom schedule in the order you want them to execute. See [[Schedule]] for more details on the following code:
 
<source lang=cpp>
AI_BEGIN_CUSTOM_NPC( npc_custom, CNPC_Custom )
DEFINE_SCHEDULE
(
SCHED_DODGE_ENEMY_FIRE,
 
" Tasks"
" TASK_FIND_DODGE_DIRECTION 3"
" TASK_JUMP 0"
""
" Interrupts"
      " COND_LIGHT_DAMAGE"
)
AI_END_CUSTOM_NPC()
</source>
 
== Task logic ==
 
Now that everything is set up it's finally time ''to write some actual AI code''.
 
* Tasks are initiated from <code>StartTask(Task_t *pTask)</code>, which should take the form of a <code>[[W:Switch statement#Examples|switch]]</code> statement that evaluates <code>pTask->iTask</code>. {{note|Remember to have a <code>default</code> case that falls back on <code>BaseClass::StartTask()</code>.}}
* Each task has an associated [[float]] value, <code>pTask->flTaskData</code>, which can be used to change its outcome.
* When the current task is complete, call <code>TaskComplete()</code>. The schedule will move on to the next task.
* If the current task has failed, call <code>TaskFail()</code> with an error message. A new schedule will be selected.
 
=== Navigation ===
 
{{todo}}
 
=== Animation ===
 
{{todo}}
 
=== Combat ===
 
{{todo}}
 
== See also ==
 
* [[Shared tasks]]
 
{{navbar|Creating a schedule|Creating an NPC|Giving an NPC Memory}}
[[Category:AI Programming]]

Revision as of 03:02, 16 September 2011

A Task is an action that an NPC can perform. Schedules will run a list of tasks. Keep tasks as atomic as possible; don't squeeze two distinct actions into the same one.

Creating a task

Custom tasks are added by first declaring a new enum value.

enum 
{
	TASK_JUMP = LAST_SHARED_TASK,
	TASK_FIND_DODGE_DIRECTION, 
	LAST_MY_NPC_TASK,
};

After that, the task itself should be declared like this:

AI_BEGIN_CUSTOM_NPC( npc_custom, CNPC_Custom )
	DECLARE_TASK( TASK_FIND_DODGE_DIRECTION )
AI_END_CUSTOM_SCHEDULE_PROVIDER()

Then you add the tasks in your custom schedule in the order you want them to execute. See Schedule for more details on the following code:

AI_BEGIN_CUSTOM_NPC( npc_custom, CNPC_Custom )
	DEFINE_SCHEDULE
	(
		SCHED_DODGE_ENEMY_FIRE,

		"	Tasks"
		"		TASK_FIND_DODGE_DIRECTION	3"
		"		TASK_JUMP	0"
		""
		"	Interrupts"
       	"		COND_LIGHT_DAMAGE"
	)
AI_END_CUSTOM_NPC()

Task logic

Now that everything is set up it's finally time to write some actual AI code.

  • Tasks are initiated from StartTask(Task_t *pTask), which should take the form of a switch statement that evaluates pTask->iTask.
    Note.pngNote:Remember to have a default case that falls back on BaseClass::StartTask().
  • Each task has an associated float value, pTask->flTaskData, which can be used to change its outcome.
  • When the current task is complete, call TaskComplete(). The schedule will move on to the next task.
  • If the current task has failed, call TaskFail() with an error message. A new schedule will be selected.

Navigation

[Todo]

Animation

[Todo]

Combat

[Todo]

See also