'===========================================================================
' Subject: STORE COLOR PALETTES              Date: 11-16-95 (13:27)       
' Author:  The ABC Programmer                Code: QB, QBasic, PDS        
' Keys:    STORE,COLOR,PALETTES            Packet: GRAPHICS.ABC
'===========================================================================
'=======================================================
' STORE COLOR PALETTES IN ARRAYS By William Yu (11/1995)
'   Demonstrates the use of Palletes in Screen 13
'=======================================================

DECLARE SUB ChangePal (Colour(), Reverse, Start)

DIM Blue(16), Red(16), Green(16)
DIM White(16)
DIM Yellow(16)
DIM Purple(16)
DIM Cyan(16)
DIM Orange(16)
DIM Pink(16)

False = 0
True = NOT False

SCREEN 13
N = 1
FOR X = 1 TO 48 STEP 3
  Blue(N) = 65536 * (X + 5) + 256
  Red(N) = 65536 + 256 + (X + 5)
  Green(N) = 65536 + 256 * (X + 5)
  White(N) = 65536 * (X + 12) + 256 * (X + 12) + (X + 12)
  Yellow(N) = 65536 + 256 * (X + 15) + (X + 15)
  Purple(N) = 65536 * (X + 15) + 256 + (X + 15)
  Cyan(N) = 65536 * (X + 15) + 256 * (X + 15)
  Orange(N) = 65536 + 256 * (X + 1) + (X + 17)
  IF X < 28 THEN
    Pink(N) = 65536 * (X + 10) + 256 * (X + .1) + (X + 10)
  ELSE
    Pink(N) = Pink(N - 8)
  END IF
  PALETTE N, Blue(N)
  PALETTE N + 16, Red(N)
  PALETTE N + 32, Green(N)
  PALETTE N + 48, White(N)
  PALETTE N + 64, Yellow(N)
  PALETTE N + 80, Purple(N)
  PALETTE N + 96, Cyan(N)
  PALETTE N + 112, Orange(N)
  PALETTE N + 128, Pink(N)
  LOCATE 1, N: COLOR N: PRINT "Û"
  LOCATE 2, N: COLOR N + 16: PRINT "Û"
  LOCATE 3, N: COLOR N + 32: PRINT "Û"
  LOCATE 4, N: COLOR N + 48: PRINT "Û"
  LOCATE 5, N: COLOR N + 64: PRINT "Û"
  LOCATE 6, N: COLOR N + 80: PRINT "Û"
  LOCATE 7, N: COLOR N + 96: PRINT "Û"
  LOCATE 8, N: COLOR N + 112: PRINT "Û"
  LOCATE 9, N: COLOR N + 128: PRINT "Û"
  N = N + 1
NEXT X

LOCATE 11, 1: PRINT "Watch while I switch the all the"
PRINT "palettes to green with CHANGEPAL"

X = 1
FOR I = 1 TO 9
  ChangePal Green(), False, X
  X = X + 16
NEXT I

COLOR 47: PRINT "Now let's go backwards!"

X = 129
FOR I = 1 TO 9
  ChangePal Orange(), True, X
  X = X - 16
NEXT I

COLOR 63: PRINT "Watch while I reverse the process."

FOR N = 1 TO 16
  PALETTE N, Blue(N)
  PALETTE N + 16, Red(N)
  PALETTE N + 32, Green(N)
  PALETTE N + 48, White(N)
  PALETTE N + 64, Yellow(N)
  PALETTE N + 80, Purple(N)
  PALETTE N + 96, Cyan(N)
  PALETTE N + 112, Orange(N)
  PALETTE N + 128, Pink(N)
NEXT N

LOCATE 17: COLOR 95: PRINT "Play around with the palettes, have fun!"

END

'
' Colour() can be any one of the defined array colour types
' Reverse  can either be TRUE or FALSE
'          if True, the palette changes from high intensity to low
'          if False, the palette changes from low to high intensity
' Start    can be any integer from which you wish to define the paletted
'          color to (Remember that an array has 16 paletted colors)
'          So if you start from 1 it'll stop at 16
'          The next starting point would be 17 and so on...
'
SUB ChangePal (Colour(), Reverse, Start)

IF Reverse THEN
  FOR I = Start + 15 TO Start STEP -1
    PALETTE I, Colour(I - Start + 1)
  NEXT I
ELSE
  FOR I = Start TO Start + 15
    PALETTE I, Colour(I - Start + 1)
  NEXT I
END IF

END SUB