Adding two codelabs for cds2014.

native_client_sdk/src/doc/cds2014/cpp.rst

+.. _cds2014_cpp:
+
+##################################
+A Saga of Fire and Water - Codelab
+##################################
+
+Introduction
+------------
+
+.. include:: cpp_summary.inc
+
+.. include:: ../nacldev/setup_app.inc
+
+Get the Code!
+-------------
+
+Rather than start from nothing, for this codelab we've provided
+you with a zip file containing a starting point.
+
+Download the codelab::
+
+  curl http://nacltools.storage.googleapis.com/cds2014/cds2014_cpp.zip -O
+
+Unzip it::
+
+  unzip cds2014_cpp.zip
+
+Go into the codelab directory::
+
+  cd cds2014_cpp
+
+Create a new local git repo::
+
+  git init
+
+Add everything::
+
+  git add .
+
+Commit it::
+
+  git commit -am "initial"
+
+While working, you can see what you've changed by running::
+
+  git diff
+
+
+Fire is cool, let's burn some stuff...
+--------------------------------------
+
+Indulging your inner child, lets make some virtual fire!
+Use the following shockingly intuitive incantation::
+
+  make fire
+
+You should now see a small popup window, smoldering away.
+If you click, you can make more fire!
+I think that'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.
+
+Water
+-----
+
+Remarkably, not everyone enjoys the primal illusion of fire.
+
+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.
+
+Before you begin, you'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::
+
+  cp fire.cc water.cc
+
+For this codelab, you'll only need to change `water.cc`.
+
+The task of turning fire into water involves two key challenges:
+
+  * Alter the red-yellow palette of fire into a blue-green one.
+  * Reverse upward rising flame into downward falling water.
+  * Seed the waterfall from the top instead of the bottom.
+
+At this point you'll want to open up `water.cc` in the editor you
+picked earlier.
+
+I see a red door and I want it painted... blue
+==============================================
+
+While PPAPI'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.
+
+Hint: Focus your energies on the CreatePalette function.
+
+You can test you changes at any time with::
+
+  make water
+
+What goes up...
+===============
+
+Now there's the small matter of gravity.
+While smoke, and well flame, rises, we want our water to go down.
+
+The simulation of fire loops over each pixel,
+bottom row to top row,
+diffusing "fire stuff" behind the sweep.
+You'll want to reverse this.
+Note the simulation buffer is stored in |row_major| from bottom to top.
+Accesses of + width and - width are used to reach rows above and below
+the current line.
+
+.. |row_major| raw:: html
+
+  <a href="http://en.wikipedia.org/wiki/Row-major_order"
+   target="_blank">Row-major order</a>
+
+Hint: You'll need to change the y loop direction in the UpdateFlames function.
+
+Up high, down low
+=================
+
+While you can now use the mouse to inject a trickle of water.
+The small line of blue at the bottom isn't much of a waterfall.
+Move it to the top to complete the effect.
+
+Hint: You'll want to change the area that the UpdateCoals function mutates.
+
+
+What you've learned
+-------------------
+
+In addition to learning a new appreciation for fire, you've also made water...
+And while dusting off your C/C++ image manipulation skills,
+you've discovered how easy it is to modify, build,
+and run a NaCl application that uses PPAPI.
+
+2D graphics is fun, but now you're ready to check out the wealth of
+other
+`PPAPI interfaces available
+<http://src.chromium.org/viewvc/chrome/trunk/src/ppapi/cpp/>`_.
+
+While our in-browser environment is rapidly evolving
+to become a complete development solution,
+for the broadest range of development options, check out the
+`NaCl SDK
+<https://developer.chrome.com/native-client/cpp-api>`_.
+
+For questions, concerns, and help contact us at
+`native-client-discuss@googlegroups.com
+<https://groups.google.com/forum/#!forum/native-client-discuss>`_.
+
+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!
+
+
+.. include:: ../nacldev/cleanup_app.inc