The feature was added in commit cb5a7aa8c32141bb Sep 2008. My description is based on "Better VGA retrace emulation (needed for some DOS games/demos)" from http://www.boblycat.org/~malc/code/patches/qemu/index.html
Signed-off-by: Matthew Ogilvie <mmogilvi_q...@miniinfo.net> --- qemu-options.hx | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/qemu-options.hx b/qemu-options.hx index 231cc4f..c50f737 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -1007,7 +1007,7 @@ DEF("vga", HAS_ARG, QEMU_OPTION_vga, "-vga [std|cirrus|vmware|qxl|xenfb|none]\n" " select video card type\n", QEMU_ARCH_ALL) STEXI -@item -vga @var{type} +@item -vga @var{type}[,@var{prop}=@var{value}[,...]] @findex -vga Select type of VGA card to emulate. Valid values for @var{type} are @table @option @@ -1032,6 +1032,12 @@ Recommended choice when using the spice protocol. @item none Disable VGA card. @end table +Valid optional properties are +@table @option +@item retrace=dumb|precise +Select dumb (default) or precise VGA retrace logic, useful for some +DOS games/demos. +@end table ETEXI DEF("full-screen", 0, QEMU_OPTION_full_screen, -- 1.7.10.2.484.gcd07cc5