manuals/chickadee/Input-Devices.html


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<span id="Input-Devices"></span><div class="header">
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<hr />
<span id="Input-Devices-1"></span><h4 class="subsection">5.1.2 Input Devices</h4>

<p>While <code>run-game</code> provides hooks for mouse/keyboard/controller
input events, it is often necessary to query input devices for their
current state.  For example, it could be desirable to query the state
of the arrow keys every time the update hook is called to determine
which direction the player should move that frame.
</p>
<dl>
<dt id="index-key_002dpressed_003f">Procedure: <strong>key-pressed?</strong> <em>key</em></dt>
<dd><p>Return <code>#t</code> if <var>key</var> is currently being pressed.
</p></dd></dl>

<dl>
<dt id="index-key_002dreleased_003f">Procedure: <strong>key-released?</strong> <em>key</em></dt>
<dd><p>Return <code>#t</code> if <var>key</var> is <em>not</em> currently being pressed.
</p></dd></dl>

<dl>
<dt id="index-mouse_002dx">Procedure: <strong>mouse-x</strong></dt>
<dd><p>Return the current X coordinate of the mouse cursor.
</p></dd></dl>

<dl>
<dt id="index-mouse_002dy">Procedure: <strong>mouse-y</strong></dt>
<dd><p>Return the current Y coordinate of the mouse cursor.
</p></dd></dl>

<dl>
<dt id="index-mouse_002dbutton_002dpressed_003f">Procedure: <strong>mouse-button-pressed?</strong> <em>button</em></dt>
<dd><p>Return <code>#t</code> if <var>button</var> is currently being pressed.
</p></dd></dl>

<dl>
<dt id="index-mouse_002dbutton_002dreleased_003f">Procedure: <strong>mouse-button-released?</strong> <em>button</em></dt>
<dd><p>Return <code>#t</code> if <var>button</var> is <em>not</em> currently being
pressed.
</p></dd></dl>

<dl>
<dt id="index-controller_002daxis">Procedure: <strong>controller-axis</strong> <em>controller axis</em></dt>
<dd><p>Return a floating point value in the range [-1, 1] corresponding to
how much <var>axis</var> (an analog stick or trigger) is being pushed on
<var>controller</var>.  0 is returned if <var>axis</var> is not being pushed at
all.
</p></dd></dl>

<dl>
<dt id="index-controller_002dname">Procedure: <strong>controller-name</strong> <em>controller</em></dt>
<dd><p>Return the name of <var>controller</var>.
</p></dd></dl>

<dl>
<dt id="index-controller_002dbutton_002dpressed_003f">Procedure: <strong>controller-button-pressed?</strong> <em>controller button</em></dt>
<dd><p>Return <code>#t</code> if <var>button</var> on <var>controller</var> is currently
being pressed.
</p></dd></dl>

<dl>
<dt id="index-controller_002dbutton_002dreleased_003f">Procedure: <strong>controller-button-released?</strong> <em>controller button</em></dt>
<dd><p>Return <code>#t</code> if <var>button</var> on <var>controller</var> is <em>not</em>
currently being pressed.
</p></dd></dl>


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