Return to structures.3r CVS log

Up to [Research Unix] / researchv10dc / 630 / man / src / p_man / man3

researchv10 Dan Cross

.ds ZZ DEVELOPMENT PACKAGE
.TH STRUCTURES 3R "630 MTG"
.XE "Word"
.XE "Code"
.XE "Point"
.XE "Rectangle"
.XE "Bitmap"
.XE "Texture16"
.XE "Font"
.XE "Fontchar"
.XE "msgbuf"
.XE "message_list"
.XE "msqid_ds"
.SH NAME
structures: Word, Code, Point, Rectangle, Bitmap, Texture16, Font, Fontchar, msgbuf, message_list, msqid_ds \- 630 MTG Structures
.SH SYNOPSIS
.ft B
#include <dmd.h>
.sp
#include <font.h>
.sp
#include <message.h>
.SH DESCRIPTION
In the following summaries,
all coordinates are screen or Bitmap coordinates
(which are scaled the same)
unless specified as window coordinates.
.I Word ,
.I Code ,
.I Point ,
.I Rectangle ,
.I Bitmap
and
.I Texture16
are included in a program
by including
.BR dmd.h .
.I Font
and
.I Fontchar
are defined in
.BR font.h .
.IR Msgbuf ,
.IR message_list ,
and
.I msqid_ds
are defined in
.BR message.h .
.SH \fIWord\fR
.RS 3
.ft CM
typedef short Word;
.br
typedef unsigned short UWord;
.RE
.PP
A
.I Word
is a 16-bit integer and is the unit of storage used in the graphics software.
.SH \fICode\fR
.RS 3
.ft CM
typedef int Code;
.RE
.PP
.I Code
is the functional constant used in all graphical drawing or copying 
operations.  Available Codes are:
.PP
.RS 3
.nf
.ft CM
F_STORE     target  =  source
F_OR        target |=  source
F_XOR       target ^=  source
F_CLR       target &= ~source
.fi
.ft 1
.RE
.SH \fIPoint\fR
.RS 3
.nf
.ft CM
typedef struct Point {
   short  x;	/* x-coordinate */
   short  y;	/* y-coordinate */
} Point;
.fi
.ft 1
.RE
.PP
A
.I Point
is a location in a
.IR Bitmap ,
such as the display.
The coordinate system has
.I x
increasing to the right and
.I y
increasing down.
.SH \fIRectangle\fR
.RS 3
.nf
.ft CM
typedef struct Rectangle {
   Point  origin;        /* Upper left corner */
   Point  corner;        /* Lower right corner*/
} Rectangle;
.fi
.ft 1
.RE
.PP
A
.I Rectangle
is a rectangular area in a
.IR Bitmap .
By definition
.BR "origin.x<=corner.x" " and " "origin.y<=corner.y"
define the rectangle.
By convention, the right (maximum \f2x\f1) and bottom (maximum \f2y\f1) edges are
excluded from the represented rectangle, so abutting rectangles have no
points in common.  Thus
.I corner
is the coordinates of the first point beyond the rectangle.
The data on the screen of the 630 MTG is contained in the
.B Rectangle
\f3{0, 0, \s-1XMAX, YMAX\s+1}\f1
where
\f3\s-1XMAX\s+1=1024\f1
and
\f3\s-1YMAX\s+1=1024\f1.
.SH \fIBitmap\fR
.RS 3
.nf
.ft CM
typedef struct Bitmap {
   Word      *base;/* pointer to start of data */
   unsigned short width;/* width in Words of total data area */
   Rectangle rect;	/* rectangle describing data area */
   char      *_null;	/* unused, must always be zero */
} Bitmap;
.fi
.ft 1
.RE
.PP
A
.I Bitmap
holds a rectangular image stored in contiguous memory starting at
.I base.
Each
.I width
words of memory form a scan-line of the image.
The
.I rect
argument
defines the coordinate system inside the
.IR Bitmap .
Argument
.I rect.origin
is the location in the
.I Bitmap
of the upper-leftmost point in the image
and is not necessarily (0,0).
Graphical operations performed on a \f2Bitmap\f1 are clipped to
.I rect.
.SH \fITexture16\fR
.RS 3
.nf
.ft CM
typedef struct Texture16 {
	Word   bits[16];
} Texture16;
.fi
.ft 1
.RE
.PP
A
.I Texture16
is a 16\(mu16 bit dot pattern.
\f2Texture16\f1's
are aligned to absolute display positions,
so adjacent areas colored with the same
.I Texture16
align smoothly.
.SH \fIFont\fR \fRand \fIFontchar\fR
.RS 3
\s-3
.nf
.ft CM
typedef struct Fontchar
{
   short         x;       /* left edge of character cell in Font.bits */
   unsigned char top;     /* first non-zero scan-line of character image */
   unsigned char bottom;  /* last non-zero scan-line of character image */
   char          left;    /* offset of baseline from x; used for kerning */
   unsigned char width;   /* width of baseline for character image */
} Fontchar;

typedef struct Font
{
   short    n;       /* number of characters in font */
   char     height;  /* height of the Bitmap bits */
   char     ascent;  /* top of Bitmap to baseline of character image */
   long     unused;
   Bitmap   *bits;   /* Bitmap where the characters are stored */
   Fontchar info[1]; /* n+1 character descriptors */
} Font;
.fi
.ft 1
.RE
.PP
A
.I Font
is a character set.  For each character in a
.I Font
there is information stored in a
.I Fontchar
structure.  
.B Font.info[n] 
is a dummy fontchar descriptor used to determine
the right edge of the last character in 
.BR Font.bits .  
The actual character images in the
.I Font
are stored in a single
.I Bitmap
pointed to by
\f2bits\f1.
The
.I Bitmap
contains the bit pattern for each character, arrayed adjacently into a
long horizontal strip.  The characters in the
.I Bitmap
must appear in ASCII order and are aligned on the same baseline.
Characters in the
.I Bitmap
abut exactly, so the width of a character
.I c
is
.BR "Font.info[c+1].x-Font.info[c].x" .
When a character is displayed on the screen at a point
.I p ,
the upper left-hand corner of the rectangle enclosing the
character image coincides with the point
.IR p .
.SH \fImsqid_ds\fR, \fImessage_list\fR and \fImsgbuf\fR
.RS 3
.nf
.ft CM
typedef struct msgbuf
{
   long	 mtype;	    /* message type */
   char	 mtext[1];	/* text of message */
} msgbuf;

typedef struct message_list
{
   msgbuf *msg;			/* the message in the queue */
   int    size;			/* size of the message */
   struct message_list  *next;	/* link to next message */
} message_list;

typedef struct msqid_ds
{
   Struct Proc	*cid;		/* creator process id */
   short		msg_qnum;	/* number of messages */
   short		msg_qbytes;	/* max number of bytes */
   Struct Proc	*msg_lspid;	/* last process to send */
   Struct Proc	*msg_lrpid;	/* last process to rcv */
   unsigned long	msg_stime;	/* time of last send */
   unsigned long	msg_rtime;	/* time of last rcv */
   unsigned long	msg_ctime;	/* time of last change */
   message_list	*msg_list;	/* linked list of messages */
   short		msg_curbytes	/* current # of bytes */
   short		state;	/* remove queue if cid exits? */
   long		name;		/* name of queue (key) */
   struct msqid_ds *next;	/* link to next queue */
} msqid_ds;
.ft 1
.fi
.RE
.PP
A
.I msqid_ds
is a message queue. The messages in the queue are kept in a linked list
referenced by the pointer
.IR msg_list .
The actual messages are stored in
.IR msgbuf s
which are pointed to by
.IR message_list .
.I Msg_qbytes
is initialized to
.B MAX_QBYTES
where
.B MAX_QBYTES=020000
(decimal 8192).
The
.I msqid_ds
is stored in a linked list in the 630 so that the number
of message queues is limited only by memory.
.SH FILES
$DMD/include/dmd.h
.br
$DMD/include/font.h
.br
$DMD/include/message.h

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.