Plan 9 from Bell Labs’s /usr/web/sources/contrib/fgb/root/sys/src/ape/X11/lib/Xfont/Speedo/do_char.c

Copyright © 2021 Plan 9 Foundation.
Distributed under the MIT License.
Download the Plan 9 distribution.


/* $Xorg: do_char.c,v 1.3 2000/08/17 19:46:24 cpqbld Exp $ */

/*

Copyright 1989-1991, Bitstream Inc., Cambridge, MA.
You are hereby granted permission under all Bitstream propriety rights to
use, copy, modify, sublicense, sell, and redistribute the Bitstream Speedo
software and the Bitstream Charter outline font for any purpose and without
restrictions; provided, that this notice is left intact on all copies of such
software or font and that Bitstream's trademark is acknowledged as shown below
on all unmodified copies of such font.

BITSTREAM CHARTER is a registered trademark of Bitstream Inc.


BITSTREAM INC. DISCLAIMS ANY AND ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE.  BITSTREAM SHALL NOT BE LIABLE FOR ANY DIRECT OR INDIRECT
DAMAGES, INCLUDING BUT NOT LIMITED TO LOST PROFITS, LOST DATA, OR ANY OTHER
INCIDENTAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF OR IN ANY WAY CONNECTED
WITH THE SPEEDO SOFTWARE OR THE BITSTREAM CHARTER OUTLINE FONT.

*/
/* $XFree86: xc/lib/font/Speedo/do_char.c,v 1.3 2001/01/17 19:43:17 dawes Exp $ */

/***************************** D O - C H A R . C *****************************
 *                                                                           *
 * This is the top level module for processing one simple or composite       *
 * character.
 *                                                                           *
 ****************************************************************************/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "spdo_prv.h"               /* General definitions for Speedo    */

#define   DEBUG   0

#if DEBUG
#include <stdio.h>
#define SHOW(X) printf("X = %d\n", X)
#else
#define SHOW(X)
#endif

/***** GLOBAL VARIABLES *****/

/*****  GLOBAL FUNCTIONS *****/

/***** EXTERNAL VARIABLES *****/

/***** EXTERNAL FUNCTIONS *****/

/***** STATIC VARIABLES *****/

/***** STATIC FUNCTIONS *****/

static boolean sp_make_simp_char(PROTO_DECL2 ufix8 FONTFAR *pointer,ufix8 format);
static boolean sp_make_comp_char(PROTO_DECL2 ufix8 FONTFAR *pointer);
static ufix8 FONTFAR *sp_get_char_org(PROTO_DECL2 ufix16 char_index,boolean top_level);
static fix15 sp_get_posn_arg(PROTO_DECL2 ufix8 FONTFAR *STACKFAR *ppointer,ufix8 format);
static fix15 sp_get_scale_arg(PROTO_DECL2 ufix8 FONTFAR *STACKFAR *ppointer,ufix8 format);


#if INCL_METRICS
FUNCTION fix31 get_char_width(
GDECL
ufix16 char_index)     /* Index to character in char directory */
/*
 * Returns character set width for specified character index in currently
 * selected font in units of 1/65536 em.
 * Reports Error 10 and returns 0 if no font selected.
 * Reports Error 12 and returns 0 if character data not available.
 */
{
ufix8 FONTFAR  *pointer;      /* Pointer to character data */
fix31    set_width;    /* Set width of character */

if (!sp_globals.specs_valid)                /* Font specs not defined? */
    {
    report_error(10);            /* Report font not specified */
    return (fix31)0;             /* Return zero character width */
    }

pointer = sp_get_char_org(char_index, TRUE); /* Get pointer to character data */
if (pointer == NULL)             /* Character data not available? */
    {
    report_error(12);            /* Report character data not avail */
    return (fix31)0;             /* Return zero character width */
    }

pointer += 2;                    /* Skip over character id */
set_width = (fix31)NEXT_WORD(pointer); /* Read set width  and Convert units */
set_width = ((set_width << 16) + (sp_globals.metric_resolution >> 1)) / sp_globals.metric_resolution;
return set_width;                /* Return in 1/65536 em units */
}
#endif

#if INCL_METRICS
#ifdef old
FUNCTION boolean get_char_bbox(
GDECL
ufix16 char_index,
bbox_t *bbox)
{
/*
 *	returns true if character exists, false if it doesn't
 *	provides transformed character bounding box in 1/65536 pixels
 *	in the provided bbox_t structure.  Bounding box may be
 *	conservative in the event that the transformation is not
 *	normal or the character is compound.
 */

ufix8 FONTFAR *pointer;
fix15 tmp;
point_t Pmin, Pmax;

#if REENTRANT_ALLOC
plaid_t plaid;
sp_globals.plaid = &plaid;
#endif

if (!sp_globals.specs_valid)                /* Font specs not defined? */
    {
    report_error(10);            /* Report font not specified */
    return FALSE;                /* Error return */
    }

init_tcb();                      /* Initialize transformation control block */

pointer = sp_get_char_org(char_index, TRUE); /* Point to start of character data */
if (pointer == NULL)             /* Character data not available? */
    {
    report_error(12);            /* Report character data not avail */
    return FALSE;                /* Error return */
    }

pointer += 2;                    /* Skip over character id */
tmp = NEXT_WORD(pointer); /* Read set width */
               
tmp = NEXT_BYTE(pointer);
if (tmp & BIT1)               /* Optional data in header? */
    {
    tmp = (ufix8)NEXT_BYTE(pointer); /* Read size of optional data */
    pointer += tmp;         /* Skip optional data */
    }

pointer = plaid_tcb(pointer, tmp);              /* Process plaid data */
pointer = read_bbox(pointer, &Pmin, &Pmax,(boolean)FALSE);        /* Read bounding box */
bbox->xmin  = (fix31)Pmin.x << sp_globals.poshift;
bbox->xmax  = (fix31)Pmax.x << sp_globals.poshift;
bbox->ymin  = (fix31)Pmin.y << sp_globals.poshift;
bbox->ymax  = (fix31)Pmax.y << sp_globals.poshift;
return TRUE;
}

#else /* new code, 4/25/91 */

FUNCTION boolean get_char_bbox(
GDECL
ufix16 char_index,
bbox_t *bbox)
{
/*
 *	returns true if character exists, false if it doesn't
 *	provides transformed character bounding box in 1/65536 pixels
 *	in the provided bbox_t structure.  Bounding box may be
 *	conservative in the event that the transformation is not
 *	normal or the character is compound.
 */

ufix8 FONTFAR *pointer;
fix15 tmp;
fix15 format;
ufix16 pix_adj;
point_t Pmin, Pmax;

#if REENTRANT_ALLOC
plaid_t plaid;
sp_globals.plaid = &plaid;
#endif

if (!sp_globals.specs_valid)                /* Font specs not defined? */
    {
    report_error(10);            /* Report font not specified */
    return FALSE;                /* Error return */
    }

init_tcb();                      /* Initialize transformation control block */

pointer = sp_get_char_org(char_index, TRUE); /* Point to start of character data */
if (pointer == NULL)             /* Character data not available? */
    {
    report_error(12);            /* Report character data not avail */
    return FALSE;                /* Error return */
    }

pointer += 2;                    /* Skip over character id */
tmp = NEXT_WORD(pointer); /* Read set width */
               
format = NEXT_BYTE(pointer);
if (format & BIT1)               /* Optional data in header? */
    {
    tmp = (ufix8)NEXT_BYTE(pointer); /* Read size of optional data */
    pointer += tmp;         /* Skip optional data */
    }

if (format & BIT0)
    {
    pix_adj = sp_globals.onepix << 1;          /* Allow 2 pixel expansion ... */
    }
else
    {
    pix_adj = 0;
    }

pointer = plaid_tcb(pointer, format);              /* Process plaid data */
pointer = read_bbox(pointer, &Pmin, &Pmax,(boolean)FALSE);        /* Read bounding box */

Pmin.x -= pix_adj;                         /* ... of components of ... */
Pmin.y -= pix_adj;                         /* ... compound ... */
Pmax.x += pix_adj;                         /* ... character ... */
Pmax.y += pix_adj;                         /* ... bounding box. */


bbox->xmin  = (fix31)Pmin.x << sp_globals.poshift;
bbox->xmax  = (fix31)Pmax.x << sp_globals.poshift;
bbox->ymin  = (fix31)Pmin.y << sp_globals.poshift;
bbox->ymax  = (fix31)Pmax.y << sp_globals.poshift;
return TRUE;
}
#endif	/* new code */

#endif


#if INCL_ISW
FUNCTION boolean make_char_isw(
GDECL
ufix16 char_index,
ufix32 imported_setwidth)
{
fix15   xmin;          /* Minimum X ORU value in font */
fix15   xmax;          /* Maximum X ORU value in font */
fix15   ymin;          /* Minimum Y ORU value in font */
fix15   ymax;          /* Maximum Y ORU value in font */
ufix16  return_value;

sp_globals.import_setwidth_act = TRUE;
/* convert imported width to orus */
sp_globals.imported_width = (sp_globals.metric_resolution * 
			    imported_setwidth) >> 16;
return_value = do_make_char(char_index);

if (sp_globals.isw_modified_constants)
    {
    /* reset fixed point constants */
    xmin = read_word_u(sp_globals.font_org + FH_FXMIN);
    ymin = read_word_u(sp_globals.font_org + FH_FYMIN);
    ymax = read_word_u(sp_globals.font_org + FH_FYMAX);
    sp_globals.constr.data_valid = FALSE;
    xmax = read_word_u(sp_globals.font_org + FH_FXMAX);
    if (!setup_consts(xmin,xmax,ymin,ymax))
        {
        report_error(3);           /* Requested specs out of range */
        return FALSE;
        }
    }    
return (return_value);
}

FUNCTION boolean make_char(
GDECL
ufix16 char_index)     /* Index to character in char directory */
{
sp_globals.import_setwidth_act = FALSE;
return (do_make_char(char_index));
}

FUNCTION static boolean do_make_char(GDECL ufix16 char_index)
#else
FUNCTION boolean make_char(GDECL ufix16 char_index)
#endif
/*
 * Outputs specified character using the currently selected font and
 * scaling and output specifications.
 * Reports Error 10 and returns FALSE if no font specifications 
 * previously set.
 * Reports Error 12 and returns FALSE if character data not available.
 */
{
ufix8 FONTFAR  *pointer;      /* Pointer to character data */
fix15    x_orus;
fix15    tmpfix15;
ufix8    format;

#if INCL_ISW
sp_globals.isw_modified_constants = FALSE;
#endif

#if REENTRANT_ALLOC

plaid_t plaid;

#if INCL_BLACK || INCL_SCREEN || INCL_2D
intercepts_t intercepts;
sp_globals.intercepts = &intercepts;
#endif

sp_globals.plaid = &plaid;
#endif

if (!sp_globals.specs_valid)                /* Font specs not defined? */
    {
    report_error(10);            /* Report font not specified */
    return FALSE;                /* Error return */
    }

#if INCL_MULTIDEV
#if INCL_OUTLINE
if (sp_globals.output_mode == MODE_OUTLINE && !sp_globals.outline_device_set)
	{
	report_error(2);
	return FALSE;
	}
else
#endif
	if (!sp_globals.bitmap_device_set)
		{
		report_error(2);
		return FALSE;
		}
#endif


init_tcb();                      /* Initialize transformation control block */

pointer = sp_get_char_org(char_index, TRUE); /* Point to start of character data */
SHOW(pointer);
if (pointer == NULL)             /* Character data not available? */
    {
    report_error(12);            /* Report character data not avail */
    return FALSE;                /* Error return */
    }

pointer += 2;                    /* Skip over character id */
x_orus = NEXT_WORD(pointer); /* Read set width */
#if INCL_SQUEEZING || INCL_ISW
sp_globals.setwidth_orus = x_orus;
#endif

#if INCL_ISW
if (sp_globals.import_setwidth_act)
    x_orus = sp_globals.imported_width;
#endif
sp_globals.Psw.x = (fix15)((fix31)
                   (((fix31)x_orus * (sp_globals.specs.xxmult>>16) + 
                  ( ((fix31)x_orus * (sp_globals.specs.xxmult&0xffffL) )>>16) 
                  ) << sp_globals.pixshift) / sp_globals.metric_resolution);

sp_globals.Psw.y = (fix15)(   
		  (fix31)( 
                 ((fix31)x_orus * (sp_globals.specs.yxmult>>16) + 
                ( ((fix31)x_orus * (sp_globals.specs.yxmult&0xffffL) )>>16) 
                  ) << sp_globals.pixshift) / sp_globals.metric_resolution);
               
format = NEXT_BYTE(pointer);
if (format & BIT1)               /* Optional data in header? */
    {
    tmpfix15 = (ufix8)NEXT_BYTE(pointer); /* Read size of optional data */
    pointer += tmpfix15;         /* Skip optional data */
    }
if (format & BIT0)
    {
    return sp_make_comp_char(pointer); /* Output compound character */
    }
else
    {
    return sp_make_simp_char(pointer, format); /* Output simple character */
    }
}

FUNCTION static boolean sp_make_simp_char(
GDECL
ufix8 FONTFAR  *pointer,      /* Pointer to first byte of position argument */
ufix8    format)       /* Character format byte */
/*
 * Called by sp_make_char() to output a simple (non-compound) character.
 * Returns TRUE on completion.
 */
{
point_t Pmin, Pmax;    /* Transformed corners of bounding box */
#if INCL_SQUEEZING || INCL_ISW
ufix8 FONTFAR *save_pointer;
#endif
#if INCL_ISW
fix31   char_width;
fix31   isw_scale;
#endif

#if INCL_SQUEEZING
sp_globals.squeezing_compound = FALSE;
if ((sp_globals.pspecs->flags & SQUEEZE_LEFT) ||
    (sp_globals.pspecs->flags & SQUEEZE_RIGHT) ||
    (sp_globals.pspecs->flags & SQUEEZE_TOP) ||
    (sp_globals.pspecs->flags & SQUEEZE_BOTTOM) )
    {
	/* get the bounding box data before processing the character */
    save_pointer = pointer;
    preview_bounding_box (pointer, format);
    pointer = save_pointer;
    }
#endif
#if (INCL_ISW)
if (sp_globals.import_setwidth_act)
    {
    save_pointer = pointer;
    preview_bounding_box (pointer, format);
    pointer = save_pointer;
        /* make sure I'm not going to get fixed point overflow */
    isw_scale = compute_isw_scale();
    if (sp_globals.bbox_xmin_orus < 0)
        char_width = SQUEEZE_MULT((sp_globals.bbox_xmax_orus - sp_globals.bbox_xmin_orus), isw_scale);
    else
	char_width = SQUEEZE_MULT(sp_globals.bbox_xmax_orus, isw_scale);
    if (char_width >= sp_globals.isw_xmax)
        if (!reset_xmax(char_width))
              return FALSE;
    }
#endif
pointer = plaid_tcb(pointer, format);              /* Process plaid data */
pointer = read_bbox(pointer, &Pmin, &Pmax, FALSE);      /* Read bounding box */
if (fn_begin_char(sp_globals.Psw, Pmin, Pmax))     /* Signal start of character output */
	{
	do
    	{
	    proc_outl_data(pointer);              /* Process outline data */
    	}
	while (!fn_end_char());                      /* Repeat if not done */
	}
return TRUE;
}

FUNCTION static boolean sp_make_comp_char(
GDECL
ufix8 FONTFAR  *pointer)      /* Pointer to first byte of position argument */
/*
 * Called by sp_make_char() to output a compound character.
 * Returns FALSE if data for any sub-character is not available.
 * Returns TRUE if output completed with no error.
 */
{
point_t  Pmin, Pmax;   /* Transformed corners of bounding box */
point_t  Pssw;         /* Transformed escapement vector */
ufix8 FONTFAR  *pointer_sav;  /* Saved pointer to compound character data */
ufix8 FONTFAR  *sub_pointer;  /* Pointer to sub-character data */
ufix8    format;       /* Format of DOCH instruction */
ufix16   sub_char_index; /* Index to sub-character in character directory */
fix15    x_posn;       /* X position of sub-character (outline res units) */
fix15    y_posn;       /* Y position of sub-character (outline res units) */
fix15    x_scale;      /* X scale factor of sub-character (scale units) */
fix15    y_scale;      /* Y scale factor of sub-character (scale units) */
fix15    tmpfix15;     /* Temporary workspace */
fix15    x_orus;       /* Set width in outline resolution units */
fix15    pix_adj;      /* Pixel adjustment to compound char bounding box */
#if INCL_SQUEEZING
fix31    x_factor, x_offset, top_scale, bottom_scale;
boolean  squeezed_x, squeezed_y;
#endif
#if INCL_SQUEEZING || INCL_ISW
fix15    x_offset_pix;
#endif
#if INCL_ISW
fix31   char_width;
fix31   isw_scale;
#endif


#if INCL_SQUEEZING
sp_globals.squeezing_compound = TRUE;
#endif
pointer = read_bbox(pointer, &Pmin, &Pmax, TRUE); /* Read bounding box data */
pix_adj = sp_globals.onepix << 1;          /* Allow 2 pixel expansion ... */
Pmin.x -= pix_adj;                         /* ... of components of ... */
Pmin.y -= pix_adj;                         /* ... compound ... */
Pmax.x += pix_adj;                         /* ... character ... */
Pmax.y += pix_adj;                         /* ... bounding box. */

#if INCL_SQUEEZING
/* scale the bounding box if necessary before calling begin_char */
squeezed_x = calculate_x_scale(&x_factor, &x_offset, 0);
squeezed_y = calculate_y_scale(&top_scale, &bottom_scale,0,0);

if (squeezed_x)
    { /* scale the x coordinates of the bbox */
    x_offset_pix = (fix15)(((x_offset >> 16) * sp_globals.tcb0.xppo)
                    >> sp_globals.mpshift);
    if ((x_offset_pix >0) && (x_offset_pix < sp_globals.onepix))
        x_offset_pix = sp_globals.onepix;
    Pmin.x = SQUEEZE_MULT (x_factor, Pmin.x) + x_offset_pix - pix_adj;
    Pmax.x = SQUEEZE_MULT (x_factor, Pmax.x) + x_offset_pix + pix_adj;
    }
if (squeezed_y)
    { /* scale the y coordinates of the bbox */
    if ((Pmin.y) < 0)
        Pmin.y = SQUEEZE_MULT (bottom_scale, Pmin.y) - pix_adj;
    else
        Pmin.y = SQUEEZE_MULT (top_scale, Pmin.y) - pix_adj;
    if ((Pmax.y) < 0)
        Pmax.y = SQUEEZE_MULT (bottom_scale, Pmax.y) + pix_adj;
    else
        Pmax.y = SQUEEZE_MULT (top_scale, Pmax.y) + pix_adj;
    }
#endif
#if (INCL_ISW)
if (sp_globals.import_setwidth_act)
    {
        /* make sure I'm not going to get fixed point overflow */
    isw_scale = ((fix31)sp_globals.imported_width << 16)/
                 (fix31)sp_globals.setwidth_orus;
    char_width = SQUEEZE_MULT((sp_globals.bbox_xmax_orus - 
                               sp_globals.bbox_xmin_orus),
isw_scale);
    if (char_width >= sp_globals.isw_xmax)
        if (!reset_xmax(char_width))
              return FALSE;
    }
#endif

if (fn_begin_char(sp_globals.Psw, Pmin, Pmax)) /* Signal start of character data */
	{
	pointer_sav = pointer;
	do
	    {
	    pointer = pointer_sav;                 /* Point to next DOCH or END instruction */
	    while ((format = NEXT_BYTE(pointer)))  /* DOCH instruction? */
	        {
	        init_tcb();                        /* Initialize transformation control block */
	        x_posn = sp_get_posn_arg(&pointer, format);
	        y_posn = sp_get_posn_arg(&pointer, (ufix8)(format >> 2));
	        x_scale = sp_get_scale_arg(&pointer, (ufix8)(format & BIT4));
	        y_scale = sp_get_scale_arg(&pointer, (ufix8)(format & BIT5));
	        scale_tcb(&sp_globals.tcb, x_posn, y_posn, x_scale, y_scale); /* Scale for sub-char */
	        sub_char_index = (format & BIT6)?  /* Read sub-char index */
		    0xffff & NEXT_WORD(pointer):
		    0xffff & NEXT_BYTE(pointer);
	        sub_pointer = sp_get_char_org(sub_char_index, FALSE); /* Point to start of sub-char */
	        if (sub_pointer == NULL)           /* Character data not available? */
	            {
	            return FALSE;                  /* Abort character output */
	            }
	        sub_pointer += 2;                  /* Skip over character id */
	        x_orus = NEXT_WORD(sub_pointer);   /* Read set_width of sub-character */

			Pssw.x = (fix15)(   
					  (fix31)( 
                              ((fix31)x_orus * (sp_globals.specs.xxmult>>16) + 
                              ( ((fix31)x_orus * (sp_globals.specs.xxmult&0xffffL) )>>16) 
                             ) << sp_globals.pixshift) / sp_globals.metric_resolution);
			Pssw.y = (fix15)(   
					  (fix31)( 
                              ((fix31)x_orus * (sp_globals.specs.yxmult>>16) + 
                              ( ((fix31)x_orus * (sp_globals.specs.yxmult&0xffffL) )>>16) 
                             ) << sp_globals.pixshift) / sp_globals.metric_resolution);
               
	        format = NEXT_BYTE(sub_pointer);   /* Read sub-character format */
	        if (format & BIT1)                 /* Optional data in header? */
	            {
	            tmpfix15 = (ufix8)NEXT_BYTE(sub_pointer); /* Read size of optional data */
	            sub_pointer += tmpfix15;           /* Skip optional data */
	            }
	        sub_pointer = plaid_tcb(sub_pointer, format);   /* Process sub-character plaid data */
	        sub_pointer = read_bbox(sub_pointer, &Pmin, &Pmax, FALSE); /* Read bounding box */
	        fn_begin_sub_char(Pssw, Pmin, Pmax);  /* Signal start of sub-character data */
	        proc_outl_data(sub_pointer);       /* Process sub-character data */
	        fn_end_sub_char();                    /* Signal end of sub-character data */
	        }
	    }
	while (!fn_end_char());                       /* Signal end of character; repeat if required */
	}
return TRUE;
}

#if INCL_LCD           /* Dynamic load character data supported? */
FUNCTION static ufix8 FONTFAR *sp_get_char_org(
GDECL
ufix16   char_index,   /* Index of character to be accessed */
boolean  top_level)    /* Not a compound character element */
/*
 * Called by sp_get_char_id(), sp_get_char_width(), sp_make_char() and
 * sp_make_comp_char() to get a pointer to the start of the character data
 * for the specified character index.
 * Version for configuration supporting dynamic character data loading.
 * Calls load_char_data() to load character data if not already loaded
 * as part of the original font buffer.
 * Returns NULL if character data not available
 */
{
buff_t  *pchar_data;   /* Buffer descriptor requested */
ufix8 FONTFAR  *pointer;      /* Pointer into character directory */
ufix8    format;       /* Character directory format byte */
fix31    char_offset;  /* Offset of char data from start of font file */
fix31    next_char_offset; /* Offset of char data from start of font file */
fix15    no_bytes;     /* Number of bytes required for char data */

if (top_level)                        /* Not element of compound char? */
    {
    if (char_index < sp_globals.first_char_idx)  /* Before start of character set? */
        return NULL;
    char_index -= sp_globals.first_char_idx;
    if (char_index >= sp_globals.no_chars_avail) /* Beyond end of character set? */
        return NULL;
    sp_globals.cb_offset = 0;                    /* Reset char buffer offset */
    }

pointer = sp_globals.pchar_dir;
format = NEXT_BYTE(pointer);          /* Read character directory format byte */
pointer += char_index << 1;           /* Point to indexed character entry */
if (format)                           /* 3-byte entries in char directory? */
    {
    pointer += char_index;            /* Adjust for 3-byte entries */
    char_offset = read_long(pointer); /* Read file offset to char data */
    next_char_offset = read_long(pointer + 3); /* Read offset to next char */
    }
else
    {
    char_offset = (fix31)(0xffff & NEXT_WORD(pointer)); /* Read file offset to char data */
    next_char_offset = (fix31)(0xffff & NEXT_WORD(pointer)); /* Read offset to next char */
    }

no_bytes = next_char_offset - char_offset;
if (no_bytes == 0)                    /* Character not in directory? */
    return NULL;

if (next_char_offset <= sp_globals.font_buff_size)/* Character data already in font buffer? */
    return sp_globals.pfont->org + char_offset;  /* Return pointer into font buffer */

pchar_data = load_char_data(char_offset, no_bytes, sp_globals.cb_offset); /* Request char data load */
if (pchar_data->no_bytes < no_bytes)  /* Correct number of bytes loaded? */
    return NULL;

if (top_level)                        /* Not element of compound char? */
    {
    sp_globals.cb_offset = no_bytes;
    }

return pchar_data->org;               /* Return pointer into character data buffer */
}
#endif

#if INCL_LCD
#else                  /* Dynamic load character data not supported? */
FUNCTION static ufix8 FONTFAR *sp_get_char_org(
GDECL
ufix16   char_index,   /* Index of character to be accessed */
boolean  top_level)    /* Not a compound character element */
/*
 * Called by sp_get_char_id(), sp_get_char_width(), sp_make_char() and
 * sp_make_comp_char() to get a pointer to the start of the character data
 * for the specified character index.
 * Version for configuration not supporting dynamic character data loading.
 * Returns NULL if character data not available
 */
{
ufix8   FONTFAR *pointer;      /* Pointer into character directory */
ufix8    format;       /* Character directory format byte */
fix31    char_offset;  /* Offset of char data from start of font file */
fix31    next_char_offset; /* Offset of char data from start of font file */
fix15    no_bytes;     /* Number of bytes required for char data */

if (top_level)                        /* Not element of compound char? */
    {
    if (char_index < sp_globals.first_char_idx)  /* Before start of character set? */
        return NULL;
    char_index -= sp_globals.first_char_idx;
    if (char_index >= sp_globals.no_chars_avail) /* Beyond end of character set? */
        return NULL;
    }

pointer = sp_globals.pchar_dir;
format = NEXT_BYTE(pointer);          /* Read character directory format byte */
pointer += char_index << 1;           /* Point to indexed character entry */
if (format)                           /* 3-byte entries in char directory? */
    {
    pointer += char_index;            /* Adjust for 3-byte entries */
    char_offset = read_long(pointer); /* Read file offset to char data */
    next_char_offset = read_long(pointer + 3); /* Read offset to next char */
    }
else
    {
    char_offset = (fix31)(0xffff & NEXT_WORD(pointer)); /* Read file offset to char data */
    next_char_offset = (fix31)(0xffff & NEXT_WORD(pointer)); /* Read offset to next char */
    }

no_bytes = next_char_offset - char_offset;
if (no_bytes == 0)                    /* Character not in directory? */
    return NULL;

return sp_globals.pfont->org + char_offset;      /* Return pointer into font buffer */
}
#endif


FUNCTION static fix15 sp_get_posn_arg(
GDECL
ufix8 FONTFAR * STACKFAR *ppointer,     /* Pointer to first byte of position argument */
ufix8    format)       /* Format of DOCH arguments */
/*
 * Called by sp_make_comp_char() to read a position argument from the
 * specified point in the font/char buffer.
 * Updates pointer to byte following position argument.
 * Returns value of position argument in outline resolution units
 */
{
switch (format & 0x03)
    {
case 1:
    return NEXT_WORD(*ppointer);

case 2:
    return (fix15)((fix7)NEXT_BYTE(*ppointer));

default:
    return (fix15)0;
    }
}

FUNCTION static fix15 sp_get_scale_arg(
GDECL
ufix8 FONTFAR *STACKFAR *ppointer,     /* Pointer to first byte of position argument */
ufix8    format)       /* Format of DOCH arguments */
/*
 * Called by sp_make_comp_char() to read a scale argument from the
 * specified point in the font/char buffer.
 * Updates pointer to byte following scale argument.
 * Returns value of scale argument in scale units (normally 1/4096)
 */
{
if (format)
    return NEXT_WORD(*ppointer);
else
    return (fix15)ONE_SCALE;
}
#if INCL_ISW || INCL_SQUEEZING
FUNCTION static void preview_bounding_box(
GDECL
ufix8 FONTFAR  *pointer,      /* Pointer to first byte of position argument */
ufix8    format)       /* Character format byte */
{
point_t  Pmin, Pmax;   /* Transformed corners of bounding box */

    sp_globals.no_X_orus = (format & BIT2)?
        (fix15)NEXT_BYTE(pointer):
        0;
    sp_globals.no_Y_orus = (format & BIT3)?
        (fix15)NEXT_BYTE(pointer):
        0;
    pointer = read_oru_table(pointer);

    /* Skip over control zone table */
    pointer = skip_control_zone(pointer,format);

    /* Skip over interpolation table */
    pointer = skip_interpolation_table(pointer,format);
    /* get_args has a pathological need for this value to be set */
    sp_globals.Y_edge_org = sp_globals.no_X_orus;
    pointer = read_bbox(pointer, &Pmin, &Pmax, TRUE);        /* Read bounding bo
x */

}
#endif
#if INCL_ISW
FUNCTION static boolean reset_xmax(
GDECL
fix31   xmax)

{
fix15   xmin;          /* Minimum X ORU value in font */
fix15   ymin;          /* Minimum Y ORU value in font */
fix15   ymax;          /* Maximum Y ORU value in font */


sp_globals.isw_modified_constants = TRUE;
xmin = read_word_u(sp_globals.font_org + FH_FXMIN);
ymin = read_word_u(sp_globals.font_org + FH_FYMIN);
ymax = read_word_u(sp_globals.font_org + FH_FYMAX);

if (!setup_consts(xmin,xmax,ymin,ymax))
    {
    report_error(3);           /* Requested specs out of range */
    return FALSE;
    }
sp_globals.constr.data_valid = FALSE;
/* recompute setwidth */
sp_globals.Psw.x = (fix15)((fix31)(
     ((fix31)sp_globals.imported_width * (sp_globals.specs.xxmult>>16) +
     ( ((fix31)sp_globals.imported_width *
          (sp_globals.specs.xxmult&0xffffL) )>>16)
     ) << sp_globals.pixshift) / sp_globals.metric_resolution);
sp_globals.Psw.y = (fix15)(   
		  (fix31)( 
                 ((fix31)sp_globals.imported_width * (sp_globals.specs.yxmult>>16) + 
                ( ((fix31)sp_globals.imported_width * (sp_globals.specs.yxmult&0xffffL) )>>16) 
                  ) << sp_globals.pixshift) / sp_globals.metric_resolution);
               
return TRUE;
}
#endif

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