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+Design of the GLES Tracing Library
+
+Code Runtime Behavior:
+
+    Initialization:
+    
+    egl_display_t::initialize() calls initEglTraceLevel() to figure out whether tracing should be
+    enabled. Currently, the shell properties "debug.egl.trace" and "debug.egl.debug_proc" together
+    control whether tracing should be enabled for a certain process. If tracing is enabled, this
+    calls GLTrace_start() to start the trace server.
+    
+    Note that initEglTraceLevel() is also called from early_egl_init(), but that happens in the
+    context of the zygote, so that invocation has no effect.
+    
+    egl_display_t::initialize() then calls setGLHooksThreadSpecific() where we set the thread
+    specific gl_hooks structure to point to the trace implementation. From this point on, every
+    GLES call is redirected to the trace implementation.
+    
+    Application runtime:
+
+    While the application is running, all its GLES calls are directly routed to their corresponding
+    trace implementation.
+
+    For EGL calls, the trace library provides a bunch of functions that must be explicitly called
+    from the EGL library. These functions are declared in glestrace.h
+
+    Application shutdown:
+
+    Currently, the application is killed when the user stops tracing from the frontend GUI. We need
+    to explore if a more graceful method of stopping the application, or detaching tracing from the
+    application is required.
+
+Code Structure:
+
+    glestrace.h declares all the hooks exposed by libglestrace. These are used by EGL/egl.cpp and
+    EGL/eglApi.cpp to initialize the trace library, and to inform the library of EGL calls.
+
+    All GL calls are present in GLES_Trace/src/gltrace_api.cpp. This file is generated by the
+    GLES_Trace/src/genapi.py script. The structure of all the functions looks like this:
+
+            void GLTrace_glFunction(args) {
+                // declare a protobuf
+                // copy arguments into the protobuf
+                // call the original GLES function
+                // if there is a return value, save it into the protobuf
+                // fixup the protobuf if necessary
+                // transport the protobuf to the host
+            }
+
+    The fixupGLMessage() call does any custom processing of the protobuf based on the GLES call.
+    This typically amounts to copying the data corresponding to input or output pointers.