                                                            
                                  COLOUR DRAW               
                       New instructions by Miles Kinloch    
                                                            
                  COLOUR DRAW  is  a  multi-colour  graphics
                  editor to create pictures with  15  colour
                  combinations per attribute cell, each  new
                  attribute having an 8 x 1 pixel format.   
                                                            
                  The picture dimensions are:               
                                                            
                  Width:  128 pixels.                       
                  Height: Min. 8, max. 192 pixels,          
                  adjustable in 8-pixel steps.              
                                                            
                  Three multi-colured pictures can be edited
                  together, and parts may be copied or moved
                  between each.                             
                                                            
                                  1. CONTROLS               
                                                            
                  Cursor movement is  controlled  with  keys
                  Q,A,O,P,M/Space,  or  with  the   Kempston
                  Joystick. No key redefinition is possible,
                  as  nearly  every  key  is  used  in   the
                  Editor's 'hot keys' system.  (For  further
                  info.  about  this  feature,  see   Editor
                  section.)                                 
                                                            
                                 2. MAIN MENU               
                                                            
                  EDITOR                                    
                  This is the main part of the program. (See
                  Editor section for details.)              
                                                            
                  LOAD/SAVE                                 
                  First, one of the three pictures  must  be
                  selected, and  also  the  storage  device,
                  i.e.  tape,  disk  or   Betadisk.   During
                  filename  input,  Symbol  Shift/Q   clears
                  anything that has been typed,  while  Edit
                  abandons the  operation  altogether.  (See
                  Load/Save    section    for    list     of
                  sub-options.)                             
                                                            
                  SHOW PICTURES                             
                  Keys 1,2,3 switch between pictures.       
                                                            
                  CLEAR PICTURE                             
                  Selects picture to clear. Set colours  and
                  then clear it.                            
                                                            
                  KEMPSTON                                  
                  Kempston Joystick on/off.                 
                                                            
                  INFORMATION                               
                  Information     about     the     authors,
                  distribution, version etc.                
                                                            
                  QUIT                                      
                  Resets computer (with option to cancel).  
                                                            
                                 3. LOAD/SAVE               
                                                            
                  LOAD SCREEN$                              
                  Loads standard 6912-byte  Spectrum  screen
                  into the selected picture. After  loading,
                  define  a  window,  moving  it  with  keys
                  Q,A,O,P and sizing it vertically with keys
                  Q and A together with Space  or  M.  Press
                  Enter to finish.                          
                                                            
                  LOAD PICTURE                              
                  Loads  COLOUR  DRAW  picture   (previously
                  saved  by  the  program).  Select  picture
                  number, then type filename.               
                                                            
                  SAVE PICTURE                              
                  Saves COLOUR DRAW picture. Select  picture
                  number, then type filename.               
                                                            
                  LOAD ATTRIBUTES                           
                  Loads only multi-coloured  attributes  (as
                  saved  previously  by   SAVE   ATTRIBUTES)
                  without pixel data. This function is  very
                  useful in conjunction with SAVE PIXELS  AS
                  SCREEN$ and LOAD SCREEN$. For example,  to
                  include  a  circle  in  the  picture,  the
                  latter may be drawn in  ART  STUDIO  etc.,
                  but  this  requires  a   standard   screen
                  format. The pixels and attributes  of  the
                  multi-coloured picture must  therefore  be
                  separated and  saved  independently,  then
                  the pixel data edited in ART  STUDIO,  and
                  pixels    and    attributes     recombined
                  afterwards in COLOUR DRAW.  (When  loading
                  the pixel data back, the section of screen
                  selected must correspond to that  when  it
                  was saved, in order for the attributes  to
                  fit!)                                     
                                                            
                  SAVE ATTRIBUTES                           
                  Saves attributes only. (See above.)       
                                                            
                  SAVE PIXELS AS SCREEN$                    
                  Saves pixels as normal 6912-byte  SCREEN$.
                  (See above.)                              
                                                            
                  SAVE PICTURE INCL. ROUTINE                
                  Saves selected picture  including  display
                  routine, so you can use  it  in  your  own
                  program.  'From  address'  refers  to  the
                  routine's start address, which must be  in
                  uncontended RAM (above  32767)  and  lower
                  than 64835. Only the length of the routine
                  itself is taken into consideration at this
                  stage, not the picture data, which will be
                  compressed later. (All length and  address
                  parameters    are     determined     after
                  compression.) 'Buffer' means the start  of
                  the buffer used by the program: its length
                  is equal to the picture height  in  pixels
                  (8-192) times 30, and  again  it  must  be
                  situated above address 32767.             
                                                            
                  After these settings have been  confirmed,
                  the pixel data will be compressed  (border
                  will flash), and further  info.  displayed
                  about the complete routine, as follows.   
                                                            
                  Routine start: Address  to  which  display
                  routine must be loaded and executed (using
                  LOAD "" CODE n: RANDOMIZE USR n).         
                                                            
                  Test routine start: Start of routine  that
                  tests computer speed.                     
                                                            
                  Whole routine length: Combined  length  of
                  display and test routines.                
                                                            
                  Picture  start:  Start  of  picture  data.
                  (Follows routine.) The number in  brackets
                  refers   to   the   address   where    the
                  information  about   the   picture   start
                  location is held.                         
                                                            
                  Picture  length:  Length   of   compressed
                  picture.                                  
                                                            
                  Total  length:  Whole  routine  length   +
                  picture length. This is the length of  the
                  code that will be saved.                  
                                                            
                  Second program address:  While  displaying
                  multi-coloured  pictures   another   short
                  machine-code program can be run every 1/50
                  second. The second program's start address
                  should be POKEd here, in standard low/high
                  byte form.                                
                                                            
                  Buffer  start:   Start   of   buffer,   as
                  selected.                                 
                                                            
                  Buffer length: Length of  buffer,  depends
                  on size of picture.                       
                  
                  Memory used: Amount of memory  needed  for
                  running  picture,  i.e.  total  length   +
                  buffer length.                            
                                                            
                  SAVE PICTURE FOR ROUTINE                  
                  Saves picture data only, without routine -
                  only one routine is required  for  showing
                  all  pictures  in  memory.  (For   further
                  info., see Routine and Pictures section.) 
                                                            
                  CATALOGUE                                 
                  Lists  disk  files.  For  tape,   displays
                  header  information  without  loading  any
                  files.                                    
                                                            
                                   4. EDITOR                
                                                            
                  First,  the  desired   picture   must   be
                  selected. All functions can be accessed by
                  a single keypress ('hot keys'  system)  or
                  through the pull-down menu. (The hot  keys
                  are  not  available  in  the   Help   Menu
                  itself.)                                  
                                                            
                                   HOT KEYS                 
                                                            
                  H: Help Menu.                             
                                                            
                  1 or I: Sets Ink colour.                  
                                                            
                  2 or Caps Shift/P: Sets Paper colour.     
                                                            
                  3 or B: Toggles Bright on/off.            
                                                            
                  4 or F: Toggles Flash on/off.             
                                                            
                  S: Transparent colours.                   
                                                            
                  5  or  C:  Applies  chosen  attributes  by
                  moving the cursor.                        
                                                            
                  6 or Symbol Shift: Memorises attributes at
                  cursor position.                          
                                                            
                  7 or N:  Copies  memorised  attributes  to
                  cursor position.                          
                                                            
                  8 or G: Grids Sub-menu:                   
                                                            
                  Set/Remove Raster: Bright grid on/off.    
                                                            
                  Set  Bright:  Applies  Bright   to   whole
                  picture.                                  
                                                            
                  Set/Remove Grid: Sets or removes grid.    
                                                            
                  9 or T: Cursor mode, i.e. toggle,  set  or
                  reset.                                    
                                                            
                  0:  Inverts  attribute  (swaps  Paper  and
                  Ink).                                     
                                                            
                  X: Border on/off. (If on, Border indicates
                  colour below cursor.)                     
                                                            
                  V:  View.  In  this  mode,  the  following
                  functions are available:                  
                                                            
                  Q,A,O,P: Position.                        
                                                            
                  Fire+Q/A: Height.                         
                                                            
                  6,7: Border colour.                       
                                                            
                  C: Copies  window.  Select  window  (using
                  Q,A,W,S,O,P to move, with Fire  to  change
                  size, and Enter to finish), then use  keys
                  1,2,3 to change picture, Fire to copy, and
                  Break or Enter to finish.                 
                                                            
                  T: Transports window. Similar to Copy, but
                  background takes  attribute  memorised  by
                  key 6 or Symbol  Shift  (see  above).  Use
                  Fire  to  transport,  Break  or  Enter  to
                  finish.                                   
                                                            
                  R: Scrolls windows.  Select  window,  then
                  use O & P to scroll (Q &  A  do  nothing),
                  together with  Fire  to  scroll  only  one
                  pixel  at  a  time.  (Attributes  are  not
                  scrolled.) Press Enter to finish, Break to
                  abandon without change. Z: Flips (mirrors)
                  window.  Select  window,  then  use   keys
                  Q,A,O,P to flip, and Enter to finish.     
                                                            
                  X: Clears window. Select, then press Enter
                  to proceed,                               
                                                            
                  Break to abandon.                         
                                                            
                  H: Picture position and height info.      
                                                            
                  1,2,3: Switches between pictures.         
                                                            
                  L+1,2,3: Loads selected picture (1,2,3) to
                  actual one.                               
                                                            
                  S+1,2,3: Saves actual picture to  selected
                  one (1,2,3).                              
                                                            
                  E+1,2,3:   Swaps   actual   picture   with
                  selected one (1,2,3).                     
                                                            
                  V or Break: Returns to Editor.            
                                                            
                  BREAK: Returns to Main Menu.              
                                                            
                            5. ROUTINE AND PICTURES         
                                                            
                  When only one picture is in memory, it can
                  be shown simply by running the routine  at
                  its start address. When there is more than
                  one, the  display  routine  must  be  told
                  whereabouts  in  memory  the  picture   of
                  interest starts. When the picture with the
                  display  routine  was  saved,  an  address
                  would have appeared in brackets  alongside
                  'Picture Start': this must be  POKEd  with
                  the low and high bytes of the  picture  to
                  be shown.                                 
                                                            
                       6. INFORMATION ABOUT THE ROUTINE     
                                                            
                  The  routine  consists  of  two  parts:  a
                  computer  speed  test  and   the   display
                  routine  itself.  The   first   of   these
                  establishes the exact machine speed, which
                  varies  between  different   models.   The
                  screen is momentarily filled with specific
                  attributes,  causing  it  to  flicker  for
                  about  1/10  second  before  the  original
                  attributes are restored, so you  may  wish
                  to use a black Paper/black Ink  background
                  while this is carried out. The speed  test
                  also switches off  Interrupt  Mode  2  and
                  sets the I register to 63.                
                                                            
                  The  time  taken  to  execute  any  second
                  routine is critical,  and  depends  to  an
                  extent  on  how  far  the  bottom  of  the
                  picture is from the  foot  of  the  screen
                  display area - the nearer, the  less  time
                  available. If too long, the display can be
                  adversely affected by excessive flicker in
                  the multi-colour  areas.  When  no  second
                  routine is  present,  its  address  should
                  point to 82 - a ROM location containing  a
                  RET instruction.                          
                                                            
                  Sound Tracker and  SQ-Tracker  tunes  make
                  compatible second routines.  No  registers
                  need be preserved.                        
