* @defgroup Win Win
*
* The window class of Elementary. Contains functions to manipulate
- * windows.
+ * windows. The Evas engine used to render the window contents is specified
+ * in the system or user elementary config files (whichever is found last),
+ * and can be overridden with the ELM_ENGINE environment variable for testing.
+ * Engines that may be supported (depending on Evas and Ecore-Evas compilation
+ * setup and modules actually installed at runtime) are (listed in order of
+ * best supported and most likely to be complete and work to lowest quality).
+ *
+ * "x11", "x", "software-x11", "software_x11"
+ * (Software rendering in X11)
+ * "gl", "opengl", "opengl-x11", "opengl_x11"
+ * (OpenGL or OpenGL-ES2 rendering in X11)
+ * "shot:..."
+ * (Virtual screenshot renderer - renders to output file and exits)
+ * "fb", "software-fb", "software_fb"
+ * (Linux framebuffer direct software rendering)
+ * "sdl", "software-sdl", "software_sdl"
+ * (SDL software rendering to SDL buffer)
+ * "gl-sdl", "gl_sdl", "opengl-sdl", "opengl_sdl"
+ * (OpenGL or OpenGL-ES2 rendering using SDL as the buffer)
+ * "gdi", "software-gdi", "software_gdi"
+ * (Windows WIN32 rendering via GDI with software)
+ * "dfb", "directfb"
+ * (Rendering to a DirectFB window)
+ * "x11-8", "x8", "software-8-x11", "software_8_x11"
+ * (Rendering in grayscale using dedicated 8bit software engine in X11)
+ * "x11-16", "x16", "software-16-x11", "software_16_x11"
+ * (Rendering in X11 using 16bit software engine)
+ * "wince-gdi", "software-16-wince-gdi", "software_16_wince_gdi"
+ * (Windows CE rendering via GDI with 16bit software renderer)
+ * "sdl-16", "software-16-sdl", "software_16_sdl"
+ * (Rendering to SDL buffer with 16bit software renderer)
+ *
+ * All engines use a simple string to select the engine to render, EXCEPT
+ * the "shot" engine. This actually encodes the output of the virtual
+ * screenshot and how long to delay in the engine string. The engine string
+ * is encoded in the following way:
+ *
+ * "shot:[delay=XX][:][file=XX]"
+ *
+ * Where options are separated by a ":" char if more than one option is given,
+ * with delay, if provided being the first option and file the last (order
+ * is important). The delay specifies how long to wait after the window is
+ * shown before doing the virtual "in memory" rendering and then save the
+ * output to the file specified by the file option (and then exit). If no
+ * delay is given, the default is 0.5 seconds. If no file is given the
+ * default output file is "out.png". Some examples of using the shot engine:
+ *
+ * ELM_ENGINE="shot:delay=1.0:file=elm_test.png" elementary_test
+ * ELM_ENGINE="shot:file=elm_test2.png" elementary_test
+ * ELM_ENGINE="shot:delay=2.0" elementary_test
+ * ELM_ENGINE="shot:" elementary_test
*
* Signals that you can add callbacks for are:
*