Q SCREEN UTILITIES
TURBO-C Version 1.0
Q screen utilities permit fast screen writes on IBM compatibles
with MDA, CGA, and/or EGA adapters without "snow" or flicker
effects and is compatible with ANY column format (e.g. 40/80 or
variable). Written in Microsoft macro-assembler, these C
functions are lightning fast. The code has also been condensed
as much as possible without sacrificing speed - only 1.6k bytes
of compiled code for all 20 functions!
Compile and run QDEMO10.C to get a feel for features and speed.
The original inline Turbo Pascal code was converted to C calling
assembler functions using the rules.asi macro file supplied with
TURBO-C. The assembler code has been revised to allow
column formats of ANY size (e.g. 40,80, or variable) and allow
global access to addresses and wait-for-retrace. This gives you
the power to have multiple pages (4 on CGA and 8 on EGA) in memory
that you already have. The filling and transfer procedures now
work in block mode rather than line mode which is faster and much
simpler with the use of Rows-by-Columns parameters.
In this version, WIND10S.LIB contains:
qinit(): Initializing procedure required to be called
before all Q utilities. Also has a function to
check for EGA cards.
Five Quick direct screen writing functions:
qwritelv() - referenced (var) strings, specified
length and index.
qwritev() - referenced (var) strings
qwrite() - value strings
qwritec() - value strings, self-centering
qwritecv() - referenced (VAR) strings, self-
Four Quick direct screen filling procedures
in Rows-by-Cols block functions:
qfillc() - repetitive filling with the same
character and self-centering
qfill() - repetitive filling with the same
qattr() - repetitive filling with the same
qattrc() - repetitive filling with the same
attribute and self-centering
Two Quick storing functions:
qstore() - Saves a Rows-by-Cols block
qrestore() - Restores a Rows-by-Cols block
to any screen page.
Two Quick direct screen changing functions:
qpage() - Changes the page to be
displayed - up to 8!
qwritepage() - Sets the page on which the
Q utilities are writing. You
don't have to write just on
the displayed page!
Four Quick cursor functions:
gotorc() - go to row/col any page
changecursor() - changes shape and visibility
of the cursor; saves old, too!
wherex() -- returns current cursor column position
wherey() -- returns cuurent cursor row position
egacheck() -- returns 1 if ega monitor
wiattr() -- returns attribute of fore/back color
qbox() -- draws a box on screen
To use the functions, just simply include
your application rograms.
Only one initializing statement is necessary qinit() before the
Q utilities are used (not required for cursor.inc):
This procedure automatically configures the procedures to your
machine and also makes it portable to others.
The coding has been reduced by making the display loops into an
assembler subroutine and programming the functions to access it.
via a CALL address. One such subroutine is present for QFILL, and
row/col - The functions do not check for bounds on the screen,
so be sure to stay in range. The functions were designed for
the upper left column on the screen to be 1,1. They also wrap to
the next line; they do not truncate at EOL. You of course can
have something like Row:=1 and Col:=255 which is equivalent to
row=3 and col=15 on a screen with 80 columns.
coll/colr - In qwritec, qwritecv, qfillc, and qattrc, the left
and right columns are simply averaged. To center on the full
width of an 80 column display, set coll:=1 and colr:=80. To
center on a certain column number, set both values equal to that
rows/cols - They can be any positive integer to define the block
- Rows-by-Columns starting at row, col. Values <=0 will simply
abort the function. Please keep cols limited to one row.
attr - The attributes range from 0 to 255. Values greater than
255 will be operated by modulo 256 to stay useful. Negative
values suppress any changes to the screen attributes and use
what's currently on the screen. For help with attribute values,
use Brian Foley's FWATTR.INC on Borland's Programming Forum on
CompuServe in Turbo Pascal Data Library for MSDOS.
length - In qwritelv, you can write partial strings by specifying
the Length and starting index (St[i]). All other qwrite procedures
assume the string to be null terminated. Length can be any positive
st - The original type was set for string length of 80 characters
which my be changed to any value between 1 and 255. Be sure to
change all type statements to reflect it though!
source/dest - For qstore/restore this can be a pointer for the heap
or an array variable. Be sure there is sufficient room. Storage
requirements are: (rows * cols << 1) which is two bytes for
every column (one for character one for attribute):
store_array = (char *)malloc(((rows * cols) << 1)*(sizeof(char)));
page - The page range depends upon your adapter as follows:
MDA - On Monochrome cards, there is only page 0.
CGA - Page 0 to 3 in modes 2 and 3 (80 column),
page 0 to 7 in modes 0 and 1 (40 column).
EGA - Page 0 to 7 in any mode (as I understand it).
foreground/background -- can be any of the colors listed in COLOR.H
btype -- can be any border type defined in (w1.h) BORDERS.
If you have a CGA or better, you already have memory on your card
for more than the 80x25 display you normally see. The two page
procedures allow you to use Q screen utilities on these other pages
and display which ever you choose. However, Turbo-C's functions
such as printf,fprintf,puts,putch are dedicated to page 0 only.
I have included gotorc as one utility that works on all pages.
Be sure to end your programs with "qpage (0);".
How fast is fast? Well, I thought it would be good idea to have
some criteria to get a feeling for speed. The units I decided
to use for comparison are "screens/second". To make one screen,
a utility is repeated with a FOR loop to fill several 80x25
pages and timed. qwriteXX use 80 character strings, and qattr
and qfill use rows=25 and Cols=80. At the moment, all I have
are ratings on my own computer (IBM XT -- NEC-V20, HERCULES CARD).
Other processors will be proportional. Monochrome (MDA)
speeds are identical to EGA speeds.
------------------ S C R E E N S / S E C O N D ------------------
Chng -- 80286 -- -- 8086 --- -- 8088 ---
Procedure Attr EGA CGA EGA CGA EGA CGA
--------- ---- ----------- ----------- ------------
qwritelv Yes 35.5 0.0
No 44.8 0.0
qwritev Yes 7.1 0.0
No 7.4 0.0
qwrite Yes 7.1 0.0
No 21.3 0.0
qwritec Yes 18.8 0.0
No 7.4 0.0
qwritecv Yes 7.1 0.0
No 21.1 0.0
qfillc Yes 100.4 0.0
No 80.9 0.0
qfill Yes 100.4 0.0
No 83.2 0.0
qattr Yes 83.2 0.0
qattrc Yes 83.2 0.0
qstore N/A 9.8 0.0
qrestore N/A 69.4 0.0
waitscreens= 0 (*COLOR SPECIFIC)
HOW IT WAS ASSEMBLED:
Microsoft Macro-Assembler 4.0 and user.asi macro files set up
to simulate C calling protocol in TURBO-C. User.asi is supplied
on the TURBO-C disks. I plan to comment the assembler source code
and release it at a later date, so other users can see how to
use macros and call assembler functions.
With the release of this utility, I hope to introduce the concept
of Teamware. These utilities are FREE, so don't worry. Many pro-
grammers have done some superior individual efforts and have
benefited many. But the problem is just that - they are individual
efforts that as packages are not compatible with other individual
efforts. And many of the programs are released as copyrighted so
that others cannot use them in certain contexts. It seems that if
users have other expertise and discover ways to combine each others
utilities, the benefits can improve greatly. This is what these
utilities have done.
As Teamware, users CAN and are encouraged to:
1. Use the utilities to enhance their programs and applications
in both private and commercial contexts.
2. Combine, create, and edit other utilities and re-release them
as Teamware by permission of the previous author(s)/editor(s).
3. Enhance shareware programs provided they are applications that
in no way represent or advertise the power of the utilities
themselves, but shall credit the use of Teamware.
4. Ask about questionable use of the utility.
As Teamware, users CANNOT:
1. Distribute the utilities for profit.
2. Combine, create, and edit other utilities and re-release them
as Shareware or for any profit as enhanced utilities.
No liabilities are assumed if the user misuses these utilities.
Without the assistance and original ideas from Brian Foley
[76317,3247], these routines would not have been written. In
Copyright (c) 1987 by Michael G. Mlachak (TURBO C)
Copyright (c) 1986 by Jim LeMay (TURBO PASCAL)
These procedures may be used and distributed without profit in
private contexts. I must be contacted for any other use.
If there are any problems such as snow, please let me know.
T U R B O --- C
Mike Mlachak[76327,1410] (1-219-397-8952 after 6:00 PM CST)
4318 Stewart Court, East Chicago, IN. 46312
T U R B O -- P A S C A L
Jim LeMay [76011,217] (1-817-735-4833 after 1800 CST )
6341 Klamath Rd., Ft. Worth, TX, 76116.
Quick Reference List of all functions and parameters:
Prototypes in (windprot.h). Type definitions in (w1.h).
** void qinit(void);
returns in global variables:
maxpage: maximum number of video pages
qwait : if 1 wait for retrace
qseg : base address of screen memory
page0seg: base address for screen 0
cardwait: same as qwait
void qwritelv (int row, col, attr,length; st str80);
void qwritev (int row, Col, attr; st str80);
void qwrite (int row, col, attr; st str80);
void qwriteC (int row, coll, colr, attr; st str80);
void qwritecv (int row, coll, colr, attr; st str80);
void qfillc (int row, coll, colr, rows, cols, attr; char ch);
void qfill (int row, col, rows, cols, attr; char ch);
void qattr (int row, col, rows, cols, attr);
void qattrC (int row, coll, colr, rows, cols, attr);
void qstore (row, col, rows, cols; char *dest);
void qrestore (row, col, rows, cols; char *source);
void qpage (int page);
void qwritepage (int byte);
void gotorc (int row, col);
int cursorchange (int new); ** RETURNS: old cursor value
int egacheck(void) -- returns 1 if ega monitor,0 otherwise
int wiattr(int foreground,background) -- returns attribute of
void qbox(int row, col, row, cols, attr, type)
Version 1.0 (6-1-87):
. Initial Routines
. Released under teamware concept