Liquidfun links

deps/include/Box2D/Documentation/Building/BuildingJavaScript.md

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+# Building JavaScript version
+
+### Background
+
+LiquidFun can be translated from C++ into JavaScript by
+[Emscripten](http://github.com/kripken/emscripten/wiki).
+The entire JavaScript translation is in one file: liquidfun.js.
+
+The LiquidFun source includes a pre-made version of liquidfun.js.
+You can reference that liquidfun.js to start writing LiquidFun programs
+in JavaScript right away.
+
+However, if you make changes to the LiquidFun C++ code, or if you need
+to expose more of the LiquidFun API, you will need to remake liquidfun.js
+by following the steps on this page.
+
+### Before Building
+
+We use Emscripten on Linux, but you should be able to use the Emscripten SDK
+on Mac or Windows too, if you prefer. Note that Mac and Windows build
+environments have not been tested.
+
+-   Get Emscripten. See [Installing from Source](http://github.com/kripken/emscripten/wiki/Emscripten-SDK#installing-from-source). 
+    -   You also need [Fastcomp](http://github.com/kripken/emscripten/wiki/LLVM-Backend#getting-fastcomp)
+    -   And [Node.js](http://nodejs.org/download/)
+-   Setup Emscripten.
+    -   As suggested in the Emscripten docs, run "emcc -v"
+    -   Update your ~/.emscripten file. You'll probably want something like this:
+        -   LLVM_ROOT = os.path.expanduser('~/Code/emscripten-fastcomp/build/Release/bin')
+        -   NODE_JS = os.path.expanduser('~/Code/node-v0.10.29-linux-x64/bin/node')
+-   Get the [Closure Compiler](http://developers.google.com/closure/compiler/).
+-   Set environment variables. Depending on your setup, you may want to add
+    some lines like this to your ~/.bashrc file.
+    - export EMSCRIPTEN=~/Code/emscripten
+    - export CLOSURE_JAR=~/Code/closure/compiler.jar
+
+### Building
+
+The following commands run Emscripten to translate C++ to lf_core.js,
+then combine lf_core.js with the bindings in jsBindings into liquidfun.js.
+
+    cd Box2D/lfjs
+    make
+    ./uglify.sh
+
+### Executing the Testbed
+
+For an example program, try openning `Box2D/lfjs/index.html' in your browser.
+This will load a JavaScript version of the LiquidFun Testbed. It uses
+the liquidfun.js file that you built above.
+
+### Debugging
+
+The default output of `make` and `uglify.sh` is whitespace-optimized
+JavaScript that is difficult to debug. To create an un-optimized version
+of the testbed, please follow the steps below.
+
++ In `lfjs/Makefile` change -O2 to -O0, to disable Emscripten optimizations.
++ In `lfjs/index.html` replace `<script src="liquidfun.js"></script>` with
+  a similar line for every .js file in `lfjs/uglify.sh`. It should look
+  something like,
+
+        <script src="lf_core.js"></script>
+        <script src="jsBindings/offsets.js"></script>
+        <script src="jsBindings/Common/b2Math.js"></script>
+        <script src="jsBindings/Collision/b2Collision.js"></script>
+        <script src="jsBindings/Collision/Shapes/b2EdgeShape.js"></script>
+        <script src="jsBindings/Collision/Shapes/b2PolygonShape.js"></script>
+        <script src="jsBindings/Collision/Shapes/b2Shape.js"></script>
+        <script src="jsBindings/Collision/Shapes/b2ChainShape.js"></script>
+        <script src="jsBindings/Collision/Shapes/b2CircleShape.js"></script>
+        <script src="jsBindings/Dynamics/b2Body.js"></script>
+        <script src="jsBindings/Dynamics/b2World.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2WheelJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2WeldJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2GearJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2Joint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2FrictionJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2RevoluteJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2MotorJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2PulleyJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2DistanceJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2PrismaticJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2RopeJoint.js"></script>
+        <script src="jsBindings/Dynamics/Joints/b2MouseJoint.js"></script>
+        <script src="jsBindings/Dynamics/Contacts/b2Contact.js"></script>
+        <script src="jsBindings/Dynamics/b2Fixture.js"></script>
+        <script src="jsBindings/Dynamics/b2WorldCallbacks.js"></script>
+        <script src="jsBindings/Particle/b2ParticleSystem.js"></script>
+        <script src="jsBindings/Particle/b2ParticleGroup.js"></script>
+        <script src="jsBindings/Particle/b2Particle.js"></script>
+