Archive Magazine CD 1995/Archive Magazine CD 1995.iso/discs/prog_disc/volume_3/issue03/info/extras/dtext

Text File | 1989-10-14 | 9.1 KB | 187 lines

DTEXT (v. 0.10)
---------------

by Chris Johnson

This software was produced to run under the old Arthur OS, and has not yet
been updated to make use of the RISC OS WIMP environment, although it does
use a mouse/menu interface. It enables text to be entered, and printed out
in a large font, four times larger than the usual printer font. Its main
use is likely to be for producing small posters, or notices for display on
notice boards, and has also been used for producing eg. overhead
transparencies for teaching purposes, giving a much neater presentation
than hand written ones.

The character set used is completely user definable, and the program has
facilities to edit an existing font, or create a new font. The characters
are defined on a 32 x 32 grid, and are proportionally spaced. Some
primitive 'kerning' is also possible for combinations of letters such as
Ta or Wa. The character set can access not only the normal printable
characters but also the corresponding 'top bit set' characters (ASCII
codes 160 - 255), assuming they have been defined.

The program contains code for both 9 pin Epson FX 8-bit double density
graphics and 24 pin Epson LQ graphics. For the 8 pin graphics (which also
work on LQ printers), each line of text uses 4 passes of the print head (8
in double strike). When 24 pin graphics are used, the character
definitions are expanded to 64 x 32, and 3 passes of the print head are
required. The height of the characters is therefore a little smaller on 24
pin printers operating in 24 pin mode. On these printers, the 8 pin
graphics also work, but the characters are expanded vertically compared
with the standard 9 pin printers, due to the different distance between
the pins in the printhead. Users of such printers will be familiar with
the different aspect ratios of these printers.



The program is driven from a set of menus and I think most of its
operation should be clear. The notes that follow may help users find their
way around the program.

Several options involve 'edit current' (text or font) or 'create new'. The
difference is that for the choice of 'new' the appropriate buffers are
cleared and you start out with a 'clean slate'. The clearing is
IRREVERSIBLE so take care! Printing is carried out on the text in memory,
so it is necessary to load a text file before any printing can be done.

When in any of the disk file loading or saving windows, operating system
commands can be used by entering the star command instead of a filename.
The * must be the FIRST character entered.


Text editing
------------

The text editor (not WYSIWYG) uses 'highlights' and 'left margin' commands
a la VIEW to produce the various effects. These include

               left justify
               centre
               right justify
               full justification
               microspacing
               double strike (not on LQ 24 bit graphics)
               tabbing
               superscript
               subscript
               thick and thin underline

The cursor keys move around the text. SHIFT with cursor key moves to start
or end of line.

A text document can contain up to 30 lines of text (an A4 page has room
for no more than 22 lines, although if single sheets are being used the
page will have less). This is normally sufficient, but can be changed by
modifying some DIM statements etc. The line length is nominally set to 57
characters as giving a reasonable length for typical text (remember the
characters are proportionally spaced so you can get far fewer upper case
letters than lower case letters in a line. However, you can switch off the
auto-format if you wish to use slightly longer lines. As in VIEW, lines
with ONLY a print command will not give a line feed, although the printer
effect will be enabled (or cancelled). A <RETURN> on its own will print as
a blank line as long as there is no other printer effect command on the
same line.

When in the text editing part of the program, the function keys are used
to insert the various printer commands. The function keys in conjunction
with SHIFT or CTRL also control some of the editing functions (eg.
insert/overwrite), and such effects as sub or superscript. A summary of
the function key actions is shown onscreen while editing. If you also have
the !keystrip application, then data is provided to print a function key
strip for use with this program. Tabbing is controlled by the TAB key,
followed by pressing a number key 1 - 9 (the 80 column width corresponds
to 960 dots, the TAB stops are set to positions 100, 200,......900). The
alternate character set is accessed by holding down the ALT key when
typing a letter. The effect is only for one character, i.e. you have to
use the ALT key in the same way as a SHIFT key, but there is nothing
corresponding to CAPS LOCK.

There is a demonstration document (DTEXT.testtext) on the disk, and it is
useful to examine this in the text editor (of this program!) to see how
the various effects are obtained. The file DTEXT.testfont will simply
print out all the defined characters of the resident font, whichever one
is loaded. The disk contains one font (FONTS.slant1) which is loaded as
the default font. Any undefined characters are ignored by the printing
procedures (not even a space is printed).

Editing a font
--------------

When editing a font, the character must be specified, and then the grid
will appear. Using ALT as well will select the top bit set character.
Pixels are set by clicking ADJUST (right button) and cleared by clicking
SELECT (left button). The button can be simply held down when setting a
row of pixels. The options in the menu are fairly self explanatory. When
moving the character within the grid, selecting with the left button will
move by one unit, while clicking with the right button will move the
character by four units. If any part of the character goes out of the
grid, then any pixels lost are NOT recoverable. The set spacing option
defines the space between the character and the next during printing. The
default is a spacing of two units. Setting a value of zero will allow the
adjacent character to join up. Remember, if you change the spacing, then
this becomes the new default value for all subsequent characters defined,
until changed again.

The reassign function is used to save a little work. For example, if you
have just designed the character P, then select the 'store character'
option to save the definition. When asked for the next character to
define, call back the P definition. This will load the defining grid with
the character P. Now select 'reassign' and reassign the definition to the
character R. The extra pixels can now be set and when the character is
stored it will be as the character R, not P.

The character definition as shown on the grid is not transferred to the
character definition buffer until the option 'store' is selected. Thus if
you begin to edit a character, and then change your mind, simply select
'abandon' from the menu. The original definition will remain unchanged.

When a definition is stored, you will be asked for the 'offset'. For most
characters this will be zero. However, for characters such as upper case T
or V, characters following which do not have a 'top' could be closed up a
little. The offset defines how many pixels a following letter of the
correct type could be closed up without overlapping. Just pressing return
will leave the current value (either default or that set when the
character was previously defined) unchanged. During the printing process
the program will close up eg. Ta but not Th as the top of the h would
interfere with the T. When the character definition is operated upon, a
flag is set if the character has a 'top', and the printing routines check
this flag to see whether the character can be closed up or not.

The stored character definitions exist only in memory during the
designing process. When you quit from the character definer, you will
be offered an opportunity to save the definitions to disk. This will
be your only chance, as you cannot save the font definition file from
the main menu. The font you have edited also remains in memory and
will be used for any printing, until another font file is loaded. As a
corollary, if you have had second thoughts about the changes you have
made to a font file then either don't save it, or at least save it
under a different filename.


If you have any comments on this program, or would like to suggest
ways in which it could be improved then the author can be contacted
directly.

Chris Johnson
7 Lovedale Grove
Balerno
Edinburgh
EH14 7DR

If you wish to enter into the `shareware' concept in the full sense
then contributions, however small, will be gratefully received by the
author. Registration would, of course, entitle the user to free
upgrades of the software (send a blank disk).

If, in any communication, you make specific reference to the program
code, then please (a) quote the version number (b) refer only to the
program as issued and (c) do not renumber it. Please send an SAE if
you require a reply.

I hope you find the program of some use. If there is sufficient
interest, then there may be a full RISC OS version produced in the
future.

CJ 12/10/1989