RASOPS(9) | Kernel Developer's Manual | RASOPS(9)

# NAME

`rasops`, `rasops_init`, `rasops_reconfig` — raster display operations

# SYNOPSIS

`#include <dev/wscons/wsdisplayvar.h>`
`#include <dev/rasops/rasops.h>`

int
`rasops_init`(struct rasops_info *ri, int wantrows, int wantcols);

int
`rasops_reconfig`(struct rasops_info *ri, int wantrows, int wantcols);

# DESCRIPTION

The `rasops` subsystem is a set of raster operations for wscons(4).

The primary data type for using the raster operations is the rasops_info structure in dev/rasops/rasops.h:

    struct rasops_info {

    	/*
    	 * These must be filled in by the caller
    	 */
    	int	ri_depth;	/* depth in bits */
    	u_char	*ri_bits;	/* ptr to bits */
    	int	ri_width;	/* width (pels) */
    	int	ri_height;	/* height (pels) */
    	int	ri_stride;	/* stride in bytes */

    	/*
    	 * These can optionally be left zeroed out. If you fill ri_font,
    	 * but aren't using wsfont, set ri_wsfcookie to -1.
    	 */
    	struct	wsdisplay_font *ri_font;
    	int	ri_wsfcookie;	/* wsfont cookie */
    	void	*ri_hw;		/* driver private data */
    	struct wsdisplay_charcell *ri_bs; /* character backing store */
    	int	ri_crow;	/* cursor row */
    	int	ri_ccol;	/* cursor column */
    	int	ri_flg;		/* various operational flags */

    	/*
    	 * These are optional and will default if zero. Meaningless
    	 * on depths other than 15, 16, 24 and 32 bits per pel. On
    	 * 24 bit displays, ri_{r,g,b}num must be 8.
    	 */
    	u_char	ri_rnum;	/* number of bits for red */
    	u_char	ri_gnum;	/* number of bits for green */
    	u_char	ri_bnum;	/* number of bits for blue */
    	u_char	ri_rpos;	/* which bit red starts at */
    	u_char	ri_gpos;	/* which bit green starts at */
    	u_char	ri_bpos;	/* which bit blue starts at */

    	/*
    	 * These are filled in by rasops_init()
    	 */
    	int	ri_emuwidth;	/* width we actually care about */
    	int	ri_emuheight;	/* height we actually care about */
    	int	ri_emustride;	/* bytes per row we actually care about */
    	int	ri_rows;	/* number of rows (characters) */
    	int	ri_cols;	/* number of columns (characters) */
    	int	ri_delta;	/* row delta in bytes */
    	int	ri_pelbytes;	/* bytes per pel (may be zero) */
    	int	ri_fontscale;	/* fontheight * fontstride */
    	int	ri_xscale;	/* fontwidth * pelbytes */
    	int	ri_yscale;	/* fontheight * stride */
    	u_char  *ri_origbits;	/* where screen bits actually start */
    	int	ri_xorigin;	/* where ri_bits begins (x) */
    	int	ri_yorigin;	/* where ri_bits begins (y) */
    	int32_t	ri_devcmap[16]; /* color -> framebuffer data */

    	/*
    	 * The emulops you need to use, and the screen caps for wscons
    	 */
    	struct	wsdisplay_emulops ri_ops;
    	int	ri_caps;

    	/*
    	 * Callbacks so we can share some code
    	 */
    	void	(*ri_do_cursor)(struct rasops_info *);
    	void	(*ri_updatecursor)(struct rasops_info *);

    #if NRASOPS_ROTATION > 0
    	/* Used to intercept putchar to permit display rotation */
    	struct	wsdisplay_emulops ri_real_ops;
    #endif
    };

The value of the ri_flg member is formed by OR'ing the following values:

RI_FULLCLEAR
  Force eraserows() to clear the whole screen instead of only text lines, when invoked with an nrows parameter equal to the number of text lines.
RI_FORCEMONO
  Do not output coloured text, even if the display supports it.
RI_BSWAP
  Specifies that the frame buffer endianness is different from the CPU's.
RI_CURSOR
  Set when the text cursor is enabled.
RI_CLEAR
  Clear the display upon initialization.
RI_CLEARMARGINS
  Clear display margins upon initialization.
RI_CENTER
  Center the text area.
RI_ROTATE_CW
  Rotate the text display quarter clockwise.
RI_ROTATE_CCW
  Rotate the text display quarter counter-clockwise.
RI_CFGDONE
  `rasops_reconfig`() completed successfully
RI_VCONS
  Support the use of multiple screens.
RI_WRONLY
  Do not read back pixels from the frame buffer memory when performing screen-to-screen copy operations. This flag is ignored unless `RI_VCONS` is set or the ri_bs member is set.

# FUNCTIONS

`rasops_init`(ri, wantrows, wantcols)
  Initialise a rasops_info descriptor. The arguments wantrows and wantcols are the number of rows and columns we'd like. In terms of optimization, fonts that are a multiple of 8 pixels wide work the best.
`rasops_reconfig`(ri, wantrows, wantcols)
  Reconfigure a rasops_info descriptor because parameters have changed in some way. The arguments wantrows and wantcols are the number of rows and columns we'd like. If calling `rasops_reconfig`() to change the font and ri_wsfcookie ≥ 0, you must call `wsfont_unlock`() on it, and reset it to -1 (or a new, valid cookie).

# CODE REFERENCES

This section describes places within the OpenBSD source tree where actual code implementing or utilising the rasops subsystem can be found. All pathnames are relative to /usr/src.

The rasops subsystem is implemented within the directory sys/dev/rasops. The `rasops` module itself is implemented within the file sys/dev/rasops/rasops.c.

# SEE ALSO

intro(9)

# HISTORY

The `rasops` subsystem appeared in NetBSD 1.5 and OpenBSD first support appeared in OpenBSD 2.9.

# AUTHORS

The `rasops` subsystem was written by Andrew Doran <ad@NetBSD.org>. Display rotation was written by Christopher Pascoe <pascoe@openbsd.org>.

# CAVEATS

Display rotation only works for 16bpp displays.

August 21, 2017 | Debian