PIX  v1.1



Program name: PIX

Jon Lindsay
150 N. Jackson Avenue, Suite 108
San Jose, CA 95116
(408) 272-4800

Hardware requirements: Kaypro with graphics.

Program function: play with the graphics features of the Kaypro.

Update: 11-03-85

Description:
This  early version was inspired by DDRAW and the Apple Macintosh 
to reflect some of the (limited) capabilities of the Kaypro 8-bit 
machine.  Admittedly  hardware dependent,  PIX was written  on  a 
Kaypro  2X  for  my  own  exploration  into  graphics.  With  the 
available  features,  one  can make some crude trackings  on  the 
screen. A severe limitation is that you cannot save your work.

Features:
          1) draw/erase a line
          2) move pixel and trail line
          3) move pixel without trailing line
          4) home pixel to preset locations
          5) paint
          6) return to any pixel location

With the initial screen, the marker pixel is
          1) in the upper left-hand corner
          2) pixel set
          3) screen blank

This means that your screen is initially blank. When you move the 
marker, it will trail a line (unless you turn it off).

UPDATE: 11-03-85
Four more "home" positions have been added to make relocating the 
pixel  marker  easier  within  the screen.  Even  better  is  the 
addition  of  a pixel location marker.  This allows you  to  work 
between ANY location, returning to that location from anywhere on 
the screen. Using keys to control pixel movement is difficult and 
takes some getting used to.

Commands:

PIXEL MOVEMENT:
The pixel movement is controlled by number pad:

    up/left      up        up/right
     7(W)       8(E)        9(R)

left 4(D/S)                 6(F/G)  right

     1(X)       2(C)        3(V)
  down/left     down      down/right

You may also use the letters in parenthesis to do the same thing. 
This makes pixel movement via the left hand a little easier.

QUIT:  Control-Q
Exit to CP/M

LOCATE PIXEL:  5
When  the marker pixel overlays another set pixel,  you can't see 
it. Tapping '5' will blink its current position.

PIXEL SET:  , (comma)
PIXEL CLEAR: - (hyphen)
With pixel set,  a trail of pixels will follow the marker as it's 
moved. With pixel clear, the pixel is moved without a trail. Note 
that this also will result in ERASING other set pixels.

LINE SET:  . (dot)
The  first dot marks the starting point of a line and the  second 
dot  the  ending point.  If pixel set is used,  as you  move  the 
marker,  you will see your own line develop.  Only when you enter 
the second dot will the program line be generated. If pixel clear 
is used,  you can move the marker anywhere on the screen  without 
creating a screen mark.  The program-generated line only  appears 
when the second dot is entered.  The generated line is a straight 
line  between the starting point and the ending point (as set  by 
the dots).  Use:  Use pixel clear and press dot key.  Move marker 
and press dot again. A line will form between the two points.

LINE ERASE:  U
Until you SET another line (dot), you can erase the previous line 
by entering a U. This will toggle the line ON and OFF, but leaves 
the marker in its current position.  Caution: if you have entered 
the  first  dot and then toggle line erase,  a "new line" can  be 
generated  based on a previous line set.  If  not  desired,  just 
toggle the U command again to erase the unwanted line.

PAINT:  Control-P
This  toggle  will force pixel set (though it can be turned  off) 
and will "drag" a line created by moving the pixel marker over  a 
given  area of the screen.  It's possible to thus "paint" a given 
screen  area.  This  is  NOT equivalent to "fill,"  which  is  an 
automatic  process  (not included with  this  program)  occurring 
within  specific  confines.  But this will let you paint up  your 
screen quickly.  Control-P starts the process;  another control-P 
stops it. Move the pixel marker normally.

HOME PIXEL:  Hn   where n = selected number
     upper left corner      upper right corner
            7                      9
                        8

                4       5      6
                              
                        2
            1                      3
     lower left corner       lower right corner

The  home  pixel command lets you place the pixel marker  in  the 
center of the screen or at one of the four corners.  It is a two-
key  command.  Use:  H3.  Marker goes immediately to lower  right 
corner.  Try this:  with the screen clear (use control-E),  input 
Example:  H7 H9 H3 H1 H4 H8 H6 H2. If using pixel set, a pixel is 
placed at each point.

SET PIXEL LOCATION:  Kn   where n = selected number (1-5)
Any point on the screen may be "marked" so that you may return to 
it at a later time. That point is retained until you use the same 
number  again.  You can have 5 locations active.  Use:  K1 = save 
current pixel location in variable #1.

RECALL PIXEL LOCATION:  Qn   where n = selected number (1-5)
This  will  restore  a previously saved pixel location  (see  SET 
PIXEL LOCATION).  Remains in effect until that number is re-used. 
If nothing was saved,  recalling the location will put the  pixel 
marker in the upper left-hand corner.

DRAW/ERASE SCREEN PERIMETER:  Control-B
This toggle will highlight the screen perimeter.

CLEAR SCREEN:  Control-E
The screen clears without changing the pixel marker position.

Terminus.