evennia/docs/1.0-dev/Howto/Weather-Tutorial.html
2020-11-14 13:44:49 +01:00

164 lines
No EOL
8.7 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Weather Tutorial &#8212; Evennia 1.0-dev documentation</title>
<link rel="stylesheet" href="../_static/nature.css" type="text/css" />
<link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
<script id="documentation_options" data-url_root="../" src="../_static/documentation_options.js"></script>
<script src="../_static/jquery.js"></script>
<script src="../_static/underscore.js"></script>
<script src="../_static/doctools.js"></script>
<script src="../_static/language_data.js"></script>
<link rel="shortcut icon" href="../_static/favicon.ico"/>
<link rel="index" title="Index" href="../genindex.html" />
<link rel="search" title="Search" href="../search.html" />
</head><body>
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="../genindex.html" title="General Index"
accesskey="I">index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="nav-item nav-item-0"><a href="../index.html">Evennia 1.0-dev</a> &#187;</li>
<li class="nav-item nav-item-this"><a href="">Weather Tutorial</a></li>
</ul>
<div class="develop">develop branch</div>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<div class="section" id="weather-tutorial">
<h1>Weather Tutorial<a class="headerlink" href="#weather-tutorial" title="Permalink to this headline"></a></h1>
<p>This tutorial will have us create a simple weather system for our MUD. The way we want to use this
is to have all outdoor rooms echo weather-related messages to the room at regular and semi-random
intervals. Things like “Clouds gather above”, “It starts to rain” and so on.</p>
<p>One could imagine every outdoor room in the game having a script running on themselves that fires
regularly. For this particular example it is however more efficient to do it another way, namely by
using a “ticker-subscription” model. The principle is simple: Instead of having each Object
individually track the time, they instead subscribe to be called by a global ticker who handles time
keeping. Not only does this centralize and organize much of the code in one place, it also has less
computing overhead.</p>
<p>Evennia offers the <a class="reference internal" href="../Components/TickerHandler.html"><span class="doc">TickerHandler</span></a> specifically for using the subscription model. We
will use it for our weather system.</p>
<p>We will assume you know how to make your own Typeclasses. If not see one of the beginning tutorials.
We will create a new WeatherRoom typeclass that is aware of the day-night cycle.</p>
<div class="highlight-python notranslate"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre> 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21</pre></div></td><td class="code"><div class="highlight"><pre><span></span>
<span class="kn">import</span> <span class="nn">random</span>
<span class="kn">from</span> <span class="nn">evennia</span> <span class="kn">import</span> <span class="n">DefaultRoom</span><span class="p">,</span> <span class="n">TICKER_HANDLER</span>
<span class="n">ECHOES</span> <span class="o">=</span> <span class="p">[</span><span class="s2">&quot;The sky is clear.&quot;</span><span class="p">,</span>
<span class="s2">&quot;Clouds gather overhead.&quot;</span><span class="p">,</span>
<span class="s2">&quot;It&#39;s starting to drizzle.&quot;</span><span class="p">,</span>
<span class="s2">&quot;A breeze of wind is felt.&quot;</span><span class="p">,</span>
<span class="s2">&quot;The wind is picking up&quot;</span><span class="p">]</span> <span class="c1"># etc </span>
<span class="k">class</span> <span class="nc">WeatherRoom</span><span class="p">(</span><span class="n">DefaultRoom</span><span class="p">):</span>
<span class="s2">&quot;This room is ticked at regular intervals&quot;</span>
<span class="k">def</span> <span class="nf">at_object_creation</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="s2">&quot;called only when the object is first created&quot;</span>
<span class="n">TICKER_HANDLER</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="mi">60</span> <span class="o">*</span> <span class="mi">60</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">at_weather_update</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">at_weather_update</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span>
<span class="s2">&quot;ticked at regular intervals&quot;</span>
<span class="n">echo</span> <span class="o">=</span> <span class="n">random</span><span class="o">.</span><span class="n">choice</span><span class="p">(</span><span class="n">ECHOES</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">msg_contents</span><span class="p">(</span><span class="n">echo</span><span class="p">)</span>
</pre></div>
</td></tr></table></div>
<p>In the <code class="docutils literal notranslate"><span class="pre">at_object_creation</span></code> method, we simply added ourselves to the TickerHandler and tell it to
call <code class="docutils literal notranslate"><span class="pre">at_weather_update</span></code> every hour (<code class="docutils literal notranslate"><span class="pre">60*60</span></code> seconds). During testing you might want to play with a
shorter time duration.</p>
<p>For this to work we also create a custom hook <code class="docutils literal notranslate"><span class="pre">at_weather_update(*args,</span> <span class="pre">**kwargs)</span></code>, which is the
call sign required by TickerHandler hooks.</p>
<p>Henceforth the room will inform everyone inside it when the weather changes. This particular example
is of course very simplistic - the weather echoes are just randomly chosen and dont care what
weather came before it. Expanding it to be more realistic is a useful exercise.</p>
</div>
<div class="clearer"></div>
</div>
</div>
</div>
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
<div class="sphinxsidebarwrapper">
<p class="logo"><a href="../index.html">
<img class="logo" src="../_static/evennia_logo.png" alt="Logo"/>
</a></p>
<div id="searchbox" style="display: none" role="search">
<h3 id="searchlabel">Quick search</h3>
<div class="searchformwrapper">
<form class="search" action="../search.html" method="get">
<input type="text" name="q" aria-labelledby="searchlabel" />
<input type="submit" value="Go" />
</form>
</div>
</div>
<script>$('#searchbox').show(0);</script>
<div role="note" aria-label="source link">
<!--h3>This Page</h3-->
<ul class="this-page-menu">
<li><a href="../_sources/Howto/Weather-Tutorial.md.txt"
rel="nofollow">Show Page Source</a></li>
</ul>
</div>
<h3>Versions</h3>
<ul>
<li><a href="Weather-Tutorial.html">1.0-dev (develop branch)</a></li>
<li><a href="../../0.9.5/index.html">0.9.5 (v0.9.5 branch)</a></li>
</ul>
</div>
</div>
<div class="clearer"></div>
</div>
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="../genindex.html" title="General Index"
>index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="nav-item nav-item-0"><a href="../index.html">Evennia 1.0-dev</a> &#187;</li>
<li class="nav-item nav-item-this"><a href="">Weather Tutorial</a></li>
</ul>
<div class="develop">develop branch</div>
</div>
<div class="footer" role="contentinfo">
&#169; Copyright 2020, The Evennia developer community.
Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 3.2.1.
</div>
</body>
</html>