sync mode emulation
Name
display-mansync : sync mode emulation
Synopis
display-mansync
Description
Helper library for the implementation of SYNC mode on targets which are inherently ASYNC (e.g. X) and require manual flushes of the framebuffer.
A target wishing to use mansync should open mansync with _ggiAddDL() in it's own GGIopen(). It must pass a pointer to a _ggi_opmansync structure as the argument to _ggiAddDL(), and must define the following macros:
MANSYNC_init(vis) MANSYNC_deinit(vis) MANSYNC_start(vis) MANSYNC_stop(vis) MANSYNC_ignore(vis) MANSYNC_cont(vis)
which is supposed to call the functions in _ggi_opmansync respectively.
Mansync provides the following functions:
int _GGI_mansync_init(vis); int _GGI_mansync_deinit(vis); Initialize/deinitialize mansync for given visual. int _GGI_mansync_start(vis); int _GGI_mansync_stop(vis); Start/stop mansync handling. (process,thread,etc.) You don't need to explicitly call these; MANSYNC_SETFLAGS does it for you. int _GGI_mansync_ignore(vis); int _GGI_mansync_cont(vis); Temporarily start/stop mansync, e.g. during mode set. It is o.k. to use them even if mansync has not been started. MANSYNC_SETFLAGS(vis,flags) mansync management in ggiSetFlags().
(The above functions return 0 if successful, -1 if not.)
Please see display/X, display/aa or display/tile to see how mansync is used. The functions should be transparent enough.
You're responsible for locking your own visual, not mansync!
Environment variables
- GGI_MANSYNC_FPS
This variable specifies the framerate for targets emulating synchronous mode. The default is 20fps. If you are experiencing problems with the X target over relatively slow remote connections it might be due to connection overload. You might want to try with a lower GGI_MANSYNC_FPS setting.