README

frecon: the Freon Console

This is a terminal emulator that replaces the kernel Virtual Terminal (VT)
console.  It uses the Kernel Mode Setting (KMS) support in the kernel.  It
is similar to the kmscon project:
	http://www.freedesktop.org/wiki/Software/kmscon


Command line options:

--clear=color
	Specify clear color for splash screen terminal. The color is 32 bit
integer in a framebuffer format (ARGB) in any format supported by strtoul.
--daemon
	Daemonize frecon.
--enable-gfx
	Enable image and box drawing OSC escape codes.
--enable-vts
	Enable additional terminals in addition to splash screen.
--frame-interval=N
	Specify default time (in miliseconds) between frames of splash screen
animation.
--gamma=/path/to/gamma/table
	Specify gamma table to apply. (unimplemented)
--loop-start=N
	Specify frame to start splash animation loop. This option also enables
the animation loop.
--loop-count=N
	Specify number of splash animation loop repetitions. (default of 0
repeats forever) Looping has to be enabled using --loop-start
--loop-interval=N
	Specify default time (in miliseconds) between frames of loop animation.
--loop-offset=x,y
	Specify default offset to centered image in loop.
--no-login
	When additional terminals are enabled do not display login prompt on
them. Can be used by scripts to display debugging information and logs on
additional terminals.
--offset=x,y
	Specify absolute location of the splash image on screen.
--print-resolution
	Print detected screen resolution and exit. Deprecated.
--scale=N
	Set default scale for splash screen images. The scale is a positive
integer number. Default scale is 1. 0 has a special meaning - using scale 1
for screens with horizontal resolution lower and equal than 1920 and 2 otherwise.
Scale affects image/box size and offset.
--splash-only
	Exit immediately after finishing splash animation. Otherwise frecon
will wait for DBUS signal (LoginScreenVisible) from Chrome before exiting
when extra terminals are not enabled.
--image=/path/to/image.png
--image-hires=/path/to/image.png
or any image file name specified after options
	Add image to splash screen animation. --image and --image-hires are
added conditionally depending whether horizontal screen resolution is below
or abover 1920. This allows frecon to make runtime decision which set of images
to use instead running frecon first with --print-resolution option and making
this decision in a script that invokes frecon.
Free form image file name in the command line are added unconditionally.

Imaging escape codes:
	Frecon implements rudimentary functionality to display images and draw
single color boxes on the terminal screen using OSC (Operating System Command)
based terminal escape codes.

The escape always starts with \033] for OSC code and ends with \033\ ST code.
Two escapes are implemented, all escape parameters can be specified in any order.

image:file=/full/path/to/file.png;location=x,y;offset=x,y;scale=s

box:size=w,h;color=c;location=x,y;offset=x,y;scale=s

location is absolute location on screen.
offset is an image offset starting with image centered on screen.
color is a 32bit number in the same format as --clear command line argument, it defaults to 0
size is two integer numbers
scale is integer scaling factor applied to image size or box size

Examples are
echo -ne "\033]image:file=/usr/share/chromeos-assets/images_100_percent/boot_splash_frame18.png\033\\" > /dev/pts/1
echo -ne "\033]box:color=0xFFFFFFFF;size=100,100\033\\" > /dev/pts/1