Yamyam: 1版をインポートしました

2018-06-28T20:50:09Z

1版をインポートしました

2012年10月1日 (月) 12:50にwiki>Sculptorjimによる

2012-10-01T12:50:16Z

新規ページ

{{Page/Header|2.6|Doc:2.6/Manual/Game Engine/Logic/Controllers}}

= Expression Controller =
This controller evaluates a user written expression, and gives a positive (TRUE) output when
;The result of the expression is TRUE, and
;The object is in the designated State.
:For all other conditions the controller gives a negative (FALSE) output.

[[File:BGE_Controller_Expression.png|right|thumb|292px|Expression Controller]]
;'''Expression'''
;The expression, which is written in the box, can consist of variables, constants and operators. These must follow the rules laid out below.

== Variables ==

You can use:

* '''sensors names''',
* '''properties''': assign a game property to an object and use it in a controller expression.

These cannot contain blank spaces.

== Operations ==

=== Mathematical operations ===

Operators: *, /, +, -

Returns: a number

Examples: 3 + 2, 35 / 5

=== Logical operations ===

* Comparison operators: <, >, >=, <=, ==, !=
* Booleans operators: AND, OR, NOT

Returns: True or False.

Examples: 3 > 2 (True), 1 AND 0 (False)

== Conditional statement (if) ==

Use:

<source lang="python">
if( expression, pulse_if_expression_is_true, pulse_if_expression_is_false )
</source>

If the controller evaluates '''<code>expression</code>''' to True:
* if '''<code>pulse_if_expression_is_true</code>''' is <code>True</code>, the controller sends a positive pulse to the connected actuators.
* if '''<code>pulse_if_expression_is_true</code>''' is <code>False</code>, the controller sends a negative pulse to the connected actuators.

If the controller evaluates '''<code>expression</code>''' to False:
* if '''<code>pulse_if_expression_is_false</code>''' is <code>True</code>, the controller sends a positive pulse to the connected actuators.
* if '''<code>pulse_if_expression_is_false</code>''' is <code>False</code>, the controller sends a negative pulse to the connected actuators.

== Examples ==

Given the object has a property '''<code>coins</code>''' equal to 30:

<source lang="python">
coins > 20
</source>

returns True (the controller sends a positive pulse to the connected actuators).

Given the object has:
* a sensor called '''<code>Key_Inserted </code>''' equal to True,
* a property named '''<code>Fuel</code>''' equal to False,

<source lang="python">
Key_Inserted AND Fuel
</source>

returns False (the controller sends a negative pulse to the connected actuators).

This is the same as doing:

<source lang="python">
if (Key_Inserted AND Fuel, True, False)
</source>

Instead, you could do:

<source lang="python">
if (Key_Inserted AND Fuel, False, True)
</source>

to return a positive pulse when '''<code>Key_Inserted AND Fuel</code>''' returns False.

You can also do:

<source lang="python">
if ((Key_Inserted AND Fuel) OR (coins > 20), True, False)
</source>

This expression returns True, hence in this case the controller sends a positive pulse to the connected actuators.

[[Category:Game engine]]

← 古い版	2018年6月28日 (木) 20:50時点における版
(相違点なし)

Doc:2.6/Manual/Game Engine/Logic/Controllers/Expression - 版の履歴

Yamyam: 1版 をインポートしました

2012年10月1日 (月) 12:50にwiki>Sculptorjimによる

Yamyam: 1版をインポートしました