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.Dd August 7, 2019
.Dt RASOPS 9
.Os
.Sh NAME
.Nm rasops ,
.Nm rasops_init ,
.Nm rasops_reconfig
.Nd raster display operations
.Sh SYNOPSIS
.In dev/wscons/wsdisplayvar.h
.In dev/rasops/rasops.h
.Ft int
.Fn rasops_init "struct rasops_info *ri" "int wantrows" "int wantcols"
.Ft int
.Fn rasops_reconfig "struct rasops_info *ri" "int wantrows" "int wantcols"
.Pp
.Cd options RASOPS_DEFAULT_WIDTH=80
.Cd options RASOPS_DEFAULT_HEIGHT=25
.Sh DESCRIPTION
The
.Nm
subsystem is a set of raster operations for
.Xr wscons 9 .
.Pp
The primary data type for using the raster operations is the
.Vt rasops_info
structure in
.In dev/rasops/rasops.h .
.Pp
Valid values for the
.Fa ri_flg
member are:
.Pp
.Bl -tag -width ".Dv RI_ENABLE_ALPHA" -offset indent -compact
.It Dv RI_FULLCLEAR
.Fn eraserows
hack to clear full screen
.It Dv RI_FORCEMONO
monochrome output even if we can do color
.It Dv RI_BSWAP
framebuffer endianness doesn't match CPU
.It Dv RI_CURSOR
cursor is switched on
.It Dv RI_CLEAR
clear display on startup
.It Dv RI_CENTER
center onscreen output
.It Dv RI_CURSORCLIP
cursor is currently clipped
.It Dv RI_CFGDONE
.Fn rasops_reconfig
completed successfully
.It Dv RI_NO_AUTO
do not generate box drawing characters for ISO fonts.
Use this when it is not safe to allocate memory, for example when setting up
an early console.
.It Dv RI_ENABLE_ALPHA
the caller supports anti-aliased fonts in the given colour depth.
Without this flag
.Fn rasops_init
will only pick bitmap fonts.
.It Dv RI_8BIT_IS_RGB
the caller uses an R3G3B2 colour map in 8 bit.
.Fn rasops_init
will generate an appropriate
.Fa ri_devcmap Ns Li []
but the caller still needs to set up the actual colour map.
.El
.Sh FUNCTIONS
.Fn rasops_init
initialises a
.Vt rasops_info
descriptor.
.Fn rasops_reconfig
is used to reconfigure it if parameters have changed in some way.
.Pp
The arguments
.Fa wantrows
and
.Fa wantcols
are the number of rows and columns we'd like.
Passing zero for either one of them uses the default \(em normally
80 by 25 but it can be changed with config options
.Dv RASOPS_DEFAULT_WIDTH
and
.Dv RASOPS_DEFAULT_HEIGHT .
.Pp
In terms of optimization, bitmap fonts of width 8 or 16 work the best
for all depths.
For depths other than 1 the fonts of width 12 are also optimized.
.Pp
If calling
.Fn rasops_reconfig
to change the font and
.Fa ri_wsfcookie
is non-negative, you must call
.Fn wsfont_unlock
on it, and reset it to \-1 or a new, valid cookie.
.Sh CODE REFERENCES
The rasops subsystem is implemented within the directory
.Pa sys/dev/rasops .
The
.Nm
module itself is implemented within the file
.Pa sys/dev/rasops/rasops.c .
.Sh SEE ALSO
.Xr intro 9 ,
.Xr wscons 9 ,
.Xr wsdisplay 9 ,
.Xr wsfont 9
.Sh HISTORY
The
.Nm
subsystem appeared in
.Nx 1.5 .
.Sh AUTHORS
The
.Nm
subsystem was written by
.An Andrew Doran
.Aq ad@NetBSD.org .