Adding two codelabs for cds2014.

native_client_sdk/doc_generated/cds2014/cpp.html

+{{+bindTo:partials.standard_nacl_article}}
+
+<section id="a-saga-of-fire-and-water-codelab">
+<span id="cds2014-cpp"></span><h1 id="a-saga-of-fire-and-water-codelab"><span id="cds2014-cpp"></span>A Saga of Fire and Water - Codelab</h1>
+<h2 id="introduction">Introduction</h2>
+<p>Learn the basics of using PPAPI to do 2D graphics from
+a C++ program running in Native Client.
+Modify our sample to turn fire into water.
+Develop inside Google Chrome, using our NaCl Development Environment
+Chrome App.
+While this codelab currently targets conventional Native Client using our
+GCC + GlibC based toolchain, the techniques involved are generally
+applicable.</p>
+<dl class="docutils">
+<dt>Requirements:</dt>
+<dd><ul class="first last small-gap">
+<li>An x86 (sorry no arm) Desktop / Laptop
+Windows, Mac, Linux, or ChromeOS browser
+<br/><span id="cpp_compat" style="color: #cccc00"
+    >Checking browser compatibility...</span><br/>
+<i id="cpp_compat2"></i>
+<script>
+var tag = document.getElementById('cpp_compat');
+var tag2 = document.getElementById('cpp_compat2');
+if (!('application/x-nacl' in navigator.mimeTypes)) {
+  tag.innerHTML =
+      'This codelab does not appear to be supported by your browser.';
+  tag.style.color = '#cc0000';
+  tag2.innerHTML =
+      'You do not appear to be running a browser such as ' +
+      'Google Chrome which supports Native Client ' +
+      'or you have disabled Native Client.';
+} else if (navigator.userAgent.search(' arm') >= 0) {
+  tag.innerHTML =
+      'This codelab does not appear to be supported by your browser.';
+  tag.style.color = '#cc0000';
+  tag2.innerHTML =
+      'You appear to be running on an ARM based CPU. ' +
+      'While Native Client does support ARM, ' +
+      "our developer environment's GCC + GlibC based toolchain " +
+      'does not, at this time. Sorry.';
+} else {
+  tag.innerHTML = 'This codelab appears to be supported by your browser.';
+  tag.style.color = '#00cc00';
+}
+</script></li>
+<li>A fast broadband connection (500MB download)</li>
+<li>Can read and write C++</li>
+</ul>
+</dd>
+</dl>
+<h2 id="setup">Setup</h2>
+<p>For this codelab, you will need to install the our
+Beta NaCl Dev Environment App in your web browser.</p>
+<a href="https://chrome.google.com/webstore/detail/nacl-development-environm/aljpgkjeipgnmdpikaajmnepbcfkglfa"
+target="_blank">Click here to install the environment.</a><p>You will need to click &#8220;Install&#8221; to add the NaCl Dev Environment
+to your browser.</p>
+<p>NOTE: This environment will leave a substantial (800MB) payload in your
+browser. See the cleanup section below to learn how to recover this space.</p>
+<p>Once the installation is complete, run the app.</p>
+<p>On the first run, it will download several packages.
+Once download is complete you should see a bash prompt:</p>
+<pre class="prettyprint">
+bash.nmf-4.3$
+</pre>
+<h3 id="our-web-based-tools">Our Web-based Tools</h3>
+<p>These development tools are a <a class="reference external" href="nacldev">work in progress</a>.
+At this point, they are a learning tool and demonstration of NaCl&#8217;s
+flexibility, but are not the recommended tools for a production application.
+In the future, that may change, but for the moment,
+to develop a substantial application for Native Client /
+Portable Native Client,
+we recommend you use the
+<a class="reference external" href="/native-client/sdk/download">Native Client SDK</a>.</p>
+<b><font color="#880000">
+NOTE: The NaCl Development Environment is not yet stable.
+Ideally user data is preserved, but currently it can be lost during updates
+or sporadically. We're working to resolve this.
+</font></b><h3 id="navigating-in-the-dev-environment">Navigating in the Dev Environment</h3>
+<p>The NaCl Dev Environment behaves like a mini-UNIX system.
+You start-up in bash command prompt.
+Standard UNIX commands like cd, ls, mkdir, rm, rmdir, etc.
+can be used to navigate and modify the Dev Environment&#8217;s
+virtual filesystem.</p>
+<p>There are 3 locations mounted by the environment:</p>
+<blockquote>
+<div><ul class="small-gap">
+<li>/tmp mounts the HTML5 Filesystem temporary storage area.</li>
+<li>/mnt/html5 mounts the HTML5 Filesystem persistent storage area.</li>
+<li>Your home directory ~/, located in /home/user,
+mounts a portion of the HTML5 Filsystem persistent storage area
+that corresponds to the /mnt/html5/home directory.</li>
+</ul>
+</div></blockquote>
+<h3 id="clipboard">Clipboard</h3>
+<p>Many of the steps in this tutorial will be easier to copy and paste
+into the Dev Environment.
+To copy and paste in the Dev Environment App,
+you will need to use the keyboard.</p>
+<p>On your platform use:</p>
+<blockquote>
+<div><ul class="small-gap">
+<li><span id="copy_key">Loading...</span>
+<script>
+var tag = document.getElementById('copy_key');
+if (navigator.appVersion.indexOf('Mac') >= 0) {
+  tag.innerHTML = '&#8984;-C';
+} else {
+  tag.innerHTML = 'Ctrl-Shift-C';
+}
+</script> to Copy</li>
+<li><span id="paste_key">Loading...</span>
+<script>
+var tag = document.getElementById('paste_key');
+if (navigator.appVersion.indexOf('Mac') >= 0) {
+  tag.innerHTML = '&#8984;-V';
+} else {
+  tag.innerHTML = 'Ctrl-Shift-V';
+}
+</script> to Paste</li>
+</ul>
+</div></blockquote>
+<h4 id="editing">Editing</h4>
+<p>To follow along in this codelab, you&#8217;ll need to use a text editor to modify
+various files in our development environment.
+There are currently two editor options, nano or vim.
+We have an Emacs port, but it is not yet available in the Dev Environment
+(coming soon).
+If you&#8217;re unsure what to pick, nano is simpler to start with and has on-screen
+help.</p>
+<ul class="small-gap">
+<li><p class="first">You can open <strong>nano</strong> like this:</p>
+<pre class="prettyprint">
+$ nano &lt;filename&gt;
+</pre>
+<p>Here&#8217;s an online <a class="reference external" href="http://mintaka.sdsu.edu/reu/nano.html">nano tutorial</a>.</p>
+</li>
+<li><p class="first">You can open <strong>vim</strong> like this:</p>
+<pre class="prettyprint">
+$ vim &lt;filename&gt;
+</pre>
+<p>Here&#8217;s an online <a class="reference external" href="http://www.openvim.com/tutorial.html">vim tutorial</a>.</p>
+</li>
+</ul>
+<h3 id="git-setup">Git Setup</h3>
+<p>This tutorial also uses a revision control program called
+<a class="reference external" href="http://en.wikipedia.org/wiki/Git_(software)">git</a>.
+In order to commit to a git repository,
+you need to setup your environment to with your identity.</p>
+<p>Run these commands (with your info) to setup your <cite>~/.gitconfig</cite>
+for use:</p>
+<pre class="prettyprint">
+git config --global user.name &quot;John Doe&quot;
+git config --global user.email johndoe&#64;example.com
+</pre>
+<h2 id="get-the-code">Get the Code!</h2>
+<p>Rather than start from nothing, for this codelab we&#8217;ve provided
+you with a zip file containing a starting point.</p>
+<p>Download the codelab:</p>
+<pre class="prettyprint">
+curl http://nacltools.storage.googleapis.com/cds2014/cds2014_cpp.zip -O
+</pre>
+<p>Unzip it:</p>
+<pre class="prettyprint">
+unzip cds2014_cpp.zip
+</pre>
+<p>Go into the codelab directory:</p>
+<pre class="prettyprint">
+cd cds2014_cpp
+</pre>
+<p>Create a new local git repo:</p>
+<pre class="prettyprint">
+git init
+</pre>
+<p>Add everything:</p>
+<pre class="prettyprint">
+git add .
+</pre>
+<p>Commit it:</p>
+<pre class="prettyprint">
+git commit -am &quot;initial&quot;
+</pre>
+<p>While working, you can see what you&#8217;ve changed by running:</p>
+<pre class="prettyprint">
+git diff
+</pre>
+<h2 id="fire-is-cool-let-s-burn-some-stuff">Fire is cool, let&#8217;s burn some stuff...</h2>
+<p>Indulging your inner child, lets make some virtual fire!
+Use the following shockingly intuitive incantation:</p>
+<pre class="prettyprint">
+make fire
+</pre>
+<p>You should now see a small popup window, smoldering away.
+If you click, you can make more fire!
+I think that&#8217;s pretty cool, but then I selected
+the institution of higher learning I attended based
+on the integral role fire played in its campus life.</p>
+<h2 id="water">Water</h2>
+<p>Remarkably, not everyone enjoys the primal illusion of fire.</p>
+<p>Your task in this codelab is to transform the rising fire
+effect you see before you, into a beautiful, tranquil waterfall.
+This will require digging into some C++ code.</p>
+<p>Before you begin, you&#8217;ll want to copy our fire program to a new name,
+since you might decide later that you like fire better, I know I do:</p>
+<pre class="prettyprint">
+cp fire.cc water.cc
+</pre>
+<p>For this codelab, you&#8217;ll only need to change <cite>water.cc</cite>.</p>
+<p>The task of turning fire into water involves two key challenges:</p>
+<blockquote>
+<div><ul class="small-gap">
+<li>Alter the red-yellow palette of fire into a blue-green one.</li>
+<li>Reverse upward rising flame into downward falling water.</li>
+<li>Seed the waterfall from the top instead of the bottom.</li>
+</ul>
+</div></blockquote>
+<p>At this point you&#8217;ll want to open up <cite>water.cc</cite> in the editor you
+picked earlier.</p>
+<h3 id="i-see-a-red-door-and-i-want-it-painted-blue">I see a red door and I want it painted... blue</h3>
+<p>While PPAPI&#8217;s 2D graphics API uses multi-component RGB pixels,
+our flame effect is actually monochrome. A single intensity
+value is used in the flame simulation. This is then converted
+to color based on a multi-color gradient.
+To alter the color-scheme, locate this palette, and exchange
+the red component for blue.</p>
+<p>Hint: Focus your energies on the CreatePalette function.</p>
+<p>You can test you changes at any time with:</p>
+<pre class="prettyprint">
+make water
+</pre>
+<h3 id="what-goes-up">What goes up...</h3>
+<p>Now there&#8217;s the small matter of gravity.
+While smoke, and well flame, rises, we want our water to go down.</p>
+<p>The simulation of fire loops over each pixel,
+bottom row to top row,
+diffusing &#8220;fire stuff&#8221; behind the sweep.
+You&#8217;ll want to reverse this.
+Note the simulation buffer is stored in <a href="http://en.wikipedia.org/wiki/Row-major_order"
+ target="_blank">Row-major order</a> from bottom to top.
+Accesses of + width and - width are used to reach rows above and below
+the current line.</p>
+<p>Hint: You&#8217;ll need to change the y loop direction in the UpdateFlames function.</p>
+<h3 id="up-high-down-low">Up high, down low</h3>
+<p>While you can now use the mouse to inject a trickle of water.
+The small line of blue at the bottom isn&#8217;t much of a waterfall.
+Move it to the top to complete the effect.</p>
+<p>Hint: You&#8217;ll want to change the area that the UpdateCoals function mutates.</p>
+<h2 id="what-you-ve-learned">What you&#8217;ve learned</h2>
+<p>In addition to learning a new appreciation for fire, you&#8217;ve also made water...
+And while dusting off your C/C++ image manipulation skills,
+you&#8217;ve discovered how easy it is to modify, build,
+and run a NaCl application that uses PPAPI.</p>
+<p>2D graphics is fun, but now you&#8217;re ready to check out the wealth of
+other
+<a class="reference external" href="http://src.chromium.org/viewvc/chrome/trunk/src/ppapi/cpp/">PPAPI interfaces available</a>.</p>
+<p>While our in-browser environment is rapidly evolving
+to become a complete development solution,
+for the broadest range of development options, check out the
+<a class="reference external" href="https://developer.chrome.com/native-client/cpp-api">NaCl SDK</a>.</p>
+<p>For questions, concerns, and help contact us at
+<a class="reference external" href="https://groups.google.com/forum/#!forum/native-client-discuss">native-client-discuss&#64;googlegroups.com</a>.</p>
+<p>I hope this codelab has lit a fire in you to go out there,
+and bring an awesome C/C++ application to NaCl or PNaCl today!</p>
+<h2 id="cleanup">Cleanup</h2>
+<p>The Chrome Dev Environment App installs &gt;800MB into
+HTML5 Filesystem storage on your device.
+To recover this storage, uninstall the app from the
+<a href="https://chrome.google.com/webstore"
+ target="_blank">Chrome Web Store</a>.</p>
+</section>
+
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