Category "IS-DOS - the programmers." No 1
Eliseev VA
"The window system IS-DOS"
(Journal version)
(C) PENCRAFT 1995
(C) IskraSoft 1995
One of the undoubted merits of the operating system IS-DOS
can be considered friendly window interface that allows
programmer you arrange your program.
The idea of windowing, absent in the traditional
operating system, ZX Spectrum, always attracted developers who
wanted to be work looked at the professional level. One of the
masterpieces of window technology is considered to be the
famous "window interface Peter Cook" used in many games,
branded programs, Art Studio, ASTRO, and even in some of the
works of local programmers - DCU, FUT, STM, F Commander
etc.
Developers of IS-DOS, naturally did not go away, and
realizing the importance and necessity of implementing a
professional system of windowing technology, gave it a whole
level of the system, called WIND.SYS.
Level WIND.SYS contains 23 restart, ensuring the work with
windows, strings of characters, cursor, etc. With these
restarts can organize information output to the display,
execution of the work screen, as well as to organize a dialogue
with the user using the line editor.
Unfortunately, the scope of this article can not review in
detail all 23 restart, the components level WIND.SYS, so it now
goes only about 19 of are directly related to working with
windows and textual information in them. Description of the
line editor and file system management panels will be separate
article under the heading "IS-DOS - the programmers."
Creating windows.
Operation of any windowing begins, naturally, with the
procedure of opening the window. Window in the IS-DOS has
following structure (see Figure 1):
pane
Workspace window
- Area frame
- Print area
- The shadow region
- Field
Fig. 1: Structure of the windows in the IS-DOS
Window area defined by the values
XS (X-size) and YS (Y-size), and is measured in
familiarity 8 * 8 pixel area frame
has a width of 8 pixels (1 familiarity
8 * 8) around the perimeter of the window, therefore, the size
of the window are XS-2 and YS-2. The size and location box,
print margins, as well as the width of the left and right
margins are determined prnt pos. and print size and is measured
in familiarity 6 * 8. The upper and lower edge of the print
limited area of the frame.
Shadow region is edging the bottom and right sides of the
window thickness of 1 familiarity 8 * 8 and indented in a
familiarity on the left and top boundaries of the window.
wt (# 61)
The system IS-DOS to open the window
use restart wt (code # 61). He
provides the formation of the on-screen window
with the parameters set in the special
table, called a "vector box".
Vector address window at the time of the call should be
restarted in the register pair IX, while the contents of
register A determines the appearance of the window as follows:
7-bit set to 1 does open a window "transparent", ie the
window opens only change the attributes
and pixels inside it are not cleared.
The remaining bits define the type of frame
window:
000000 - Single Frame
000010 - double frame
All other values lead to the discovery of a window
without frames.
Thus, the format specify the appearance of the window can
be represented as table:
single-double without
Window frame frame frame
A = # 81
trans-A = # A = # 80 82 A = # 83
Noe # FF
A = # 01
neproz-A = # A = # 00 02 A = # 03 # 7F rachnoe
Thus, the procedure of opening windows on the IS-DOS as
follows:
LD IX, WIND; loading in IX
; Address vector
The windows
LD C, # 61; loading into C code
; Restart wt
LD A, n; load in A values
; Radiation, which determines
; Sheha window view
RST # 10; call restart
The structure of the vector window:
WIND DEFB # 00; X-coordinate of the top
; He left corner
The windows in the familiarity
, 8 * 8 pixels
DEFB # 00; Y-coordinate of the top
; He left corner
The windows in the familiarity
, 8 * 8 pixels
coordinate values are measured from the top left corner of
the screen
DEFB # 0F; height windows in the value
; COMEST 8 * 8
DEFB # 0F; width of the window in the value
; COMEST 8 * 8
DEFB% 00000111; color box
color coded in a standard way:
Bit 7 - flash
Bit 6 - bright
Bits 5 ... 3 - paper
bits 2 ... 0 - ink
DEFB% 00000001; color shadow box
It is noteworthy that in the colors of the shadow box can
be set as the color of paper, and color ink, which allows us to
make visible part of the information on which the shadow
from the window and maximizes natural perception. If the byte
is equal to the color shade # FF, then the shadow is not
displayed.
DEFB # 01; X-coordinate for
; The routine
; Text in the box
DEFB # 12; field width Pec
; Tee box
The last two parameters are expressed in
familiarity size 6 * 8 instead of 8 * 8 as
the rest is done because such
reference system used by all restarts
Printing IS-DOS. The value of X-coordinates
Print absolute, and is measured not by
the left border of the window, and from the left border
screen. Translate the coordinates of the window in kooordinaty
print and vice versa can be done by the formulas:
(1) n = N * 8 / 6
(2) N = n * 6 / 8,
where n - the value of familiarity 6 * 8,
and N - a value in familiarity 8 * 8.
Y-coordinate of the Print is not specified, so
most of the restarts print yourself counts her from the top of
the line box.
The screen can be opened multiple windows, and the current
will be a window, the address of the vector which is in the
register pair IX. In order to more rational use of
RAM information, closes the window at the time of its opening
is not preserved, so if you suddenly needed to go back to the
previous window, you'll need it rediscover.
Consider a simple example. Problem
- Create a point with coordinates X = 5 and
Y = 3 box of 28 * 16 familiarity with a double frame, blue
paper, white ink and black-and-blue shade, the field of print
text indented to define a familiarity of the left and a
5-familiarity of the right the window border.
To create this simple program except restart the window
opening wt (# 61) We need another three routines -
clear the screen, wait keypress
and return to the IS-DOS.
The effect of these routines is based on
Other system resets IS-DOS, which
will be described in the next issue, but so far just remember
them:
CLS LD C, # 73; restart cls
RST # 10; to clear the screen
RET
WAIT LD C, # 07; restart ttyin
RST # 10; to wait for the clicking
RET; Tia Keys
EXIT XOR A; standard output
LD A, # F4; in the IS-DOS
RET
So, consider Listing 1:
;****************************************
; Listing 1: Example of creating a window
; Background:
; X-coord (X) = 5
; Y-coord (Y) = 3
; X-size (XS) = 20
; Y-size (YS) = 16
; W. Colors (WC) =% 00001111
; S. Colors (SC) =% 00000001
; L. Margin (LM) = 1
; R. Margin (RM) = 5
ORG # 5D64
; The main program
START CALL CLS; procedure call
; Clear the screen
LD IX, WIND; address vector window
LD C, # 61; code restart wt
LD A, 2; code double frame
RST # 10; call restart
CALL WAIT; procedure call
; Standby button
JP EXIT; transition to procedure
; Fool return to
; IS-DOS
And the vector window
WIND DEFB 5
DEFB 3
DEFB 16
DEFB 20
DEFB% 00001111
DEFB% 00000001
DEFB 8
DEFB 20
; Data for the print position (printing
; Indented familiarity in 1 6 * 8 of the left
; Of the window) were obtained by calculating on
; (3):
(3) PP = X * 8 / 6 + LM,
, Where PP - print pos. familiarity in the 6 * 8
; X - X-coord. windows familiarity 8 * 8
; LM - left field in the familiarity 6 * 8
; Data for the print size obtained by
, Calculated by formula (4):
(4) PS = XS * 8/6-LM-RM,
, Where PS - print size in the familiarity 6 * 8
; XS - window size in the familiarity 8 * 8
; LM - left field in the familiarity 6 * 8
; RM - right-field familiarity 6 * 8
; Additional procedures
CLS LD C, # 73; restart cls
RST # 10; to clear the screen
RET
WAIT LD C, # 07; restart ttyin
RST # 10; to wait
RET; pressing
EXIT XOR A; standard output
LD A, # F4; in the IS-DOS
RET
;****************************************
As a result, program execution
Listing 1 on the screen should get a window, the corresponding
image in Figure 2, otherwise, check your dialing program.
Fig. 2: The output of the program
Listing 1
...
box (# 62)
Next restart the box (# 62) allows
draw or erase in the frame
window every possible frame, or any of the
her side in any combination. Since
the width of the window frame in IS-DOS is
8 pixels, with maybe 8 different
single framework. Causing restart box a few times you can draw
double, triple and even quad frame, as well as frames of
varying thickness - only 256 combinations.
As input parameters restart box (# 62) uses a vector of the
window at the address given in register IX, and also the values
of the indentation from the edge of the window in the Y and X
in pixels defined in registers D and E, respectively, and the
contents Register A, indicating that it is required to draw or
erase.
The contents of register A is determined
as follows:
Bit 7 = 0 - Draw 1 - Wash
Bits 6 ... 4 - not used
the other bits indicate which of the
party framework is the operation:
Bit 3 = 0 - left side frame
bit 2 = 0 - right-hand side of the frame
bit 1 = 0 - the upper side frame
Bit 0 = 0 - the lower side of the frame
The bits 3 ... 0 is possible in any combination.
Shared form of procedure of drawing / erasing frame looks
like this:
LD IX, WIND; address vector window
LD C, # 62; code restart box
LD D, N1; indented with Y
LD E, N2; indented with X
LD A, n; what to do
RST # 10; call restart
To set the values of the indent beyond
preferable to use the numbers from 0
to 7, and when loaded into the registers D and
E values of 0 frame will be displayed on the outer edge of
the window, and when loading the values 7 - on the inner edge
of the frame. Value of 8 has the same effect as 0, 9-same as 1,
etc.
Consider an example. As a basis
take Listing 1, but depict the first
window without the frame, and then derive the double
frame so that its outer line was
twice as wide as the inside, and then make a left and right
sides of the outer frame single thickness.
;****************************************
; Listing 2 Example of a drawing of the window frame
ORG # 5D64
, Opening a window
START CALL CLS; clear screen
LD IX, WIND
LD C, # 1961
LD A, 1; window without frames
RST # 10
CALL WAIT
, Drawing the outer frame double thickness
; Performed in two steps
LD IX, WIND; address vector window
LD C, # 62; code rstarta box
LD D, 0; indented with Y
LD E, 0; margin of X
LD A,% 00000000
And all the bits ravney 0 - to draw an entire frame
RST # 10
LD IX, WIND
LD C, # 1962
LD D, 1
LD E, 1
LD A,% 00000000
RST # 10
CALL WAIT
, Drawing the inner frame
LD IX, WIND
LD C, # 1962
LD D, 3
LD E, 3
LD A,% 00000000
RST # 10
CALL WAIT
; Wipe the sides of the
LD IX, WIND
LD C, # 1962
LD D, 2
LD E, 1
LD A,% 10000011
, 7-th bit is set - the team erase
; Set 0-th and 1 th bits designate,
; Not affected in this operation, the upper
, And the lower side of the frame
RST # 10
CALL WAIT
JR EXIT
And the vector window
WIND DEFB 5
DEFB 3
DEFB 16
DEFB 20
DEFB% 00001111
DEFB% 00000001
DEFB 8
DEFB 20
; Additional procedures
CLS LD C, # 1973
RST # 10
RET
WAIT LD C, # 2007
RST # 10
RET
EXIT XOR A
LD A, # F4
RET
;****************************************
If necessary, the organization framework
drawing vertical and horizontal
lines within the window (outside the region
frame) can also use the services
restart the box (# 62), however, this will create a fictitious
vector window so that the desired frame is within the area
beyond this imaginary box.
Let us explain with an example:
Suppose you want to create inside the box
(See Listing 1) frame with an indent of 2 familiarity from the
top of the window in a 4 - to the bottom and 3 from the left
and right sides.
To do this, create a dummy vector
windows WIND1, and for the calculation of its parameters
use the following formula:
(5) Y1 = Y + UM,
where Y1 - Y-coordinate frame,
Y - Y-coordinate of window
UM - upper margin
(6) X1 = X + LM,
where X1 - X-coordinate frame,
X - X-coordinate of window
LM - left indent
(7) YS1 = YS-UM-DM,
where YS1 - frame size on Y,
YS - window size on Y,
UM - space from above,
DM - padding bottom
(8) XS1 = XS-LM-RM,
where XS1 - frame size on X,
XS - window size X,
LM - left indent,
RM - right margin
All values are measured in familiarity 8 * 8. Color
values we choose same as in the main window, but without a
shadow (S. Colors = # FF), meaning Print pos. and
Print size can be arbitrary.
Thus,
;****************************************
; Listing 3 Example of a drawing of internal
; Frames with box (# 62)
; Background:
; Up Margin (UM) = 2
; Down Margin (DM) = 4
; Left Margin (LM) = 3
; Right Margin (RM) = 3
ORG # 5D64
, Opening a window
START CALL CLS; clear screen
LD IX, WIND
LD C, # 1961
LD A, 2
RST # 10
CALL WAIT
, Draw a second box is not required
; Enough to just put the address of its
; Vector in register IX to transfer
; Parameters restart box
, Drawing a frame within a window
LD IX, WIND1; vector scope
LD C, # 1962
LD D, 0
LD E, 0
LD A,% 00000000
RST # 10
CALL WAIT
JR EXIT
And the vector window
WIND DEFB 5
DEFB 3
DEFB 16
DEFB 20
DEFB% 00001111
DEFB% 00000001
DEFB 8
DEFB 20
And the vector window for the frame
WIND1 DEFB 8
DEFB 5
DEFB 10
DEFB 14
DEFB% 00001111
DEFB # FF
DEFB # 00
DEFB # 00
; Additional procedures
CLS LD C, # 1973
RST # 10
RET
WAIT LD C, # 2007
RST # 10
RET
EXIT XOR A
LD A, # F4
RET
;****************************************
As a result of the program Listing 3 on the screen should
get a picture shown in Fig. 3
Fig. 3: The output of the program
Listing 3
Similarly, run vertical or horizontal lines - they
presented as an imaginary part
frame and are given a fictitious vector window.
Selecting the contents of registers D and E it is easy to
achieve positioning the frame or line to within 1 pixel.
To be continued ...
In the next issue we will talk about the other
no less important group of system restarts IS-DOS - restart
printing characters and lines.
