'===========================================================================
' Subject: FLIP UPSIDE DOWN INT GET-ARRAY    Date: 01-07-99 (12:34)       
' Author:  Jacob Wieles                      Code: QB, PDS, PB            
' Origin:  jacwls@worldonline.nl           Packet: GRAPHICS.ABC
'===========================================================================
'program        : T-B-INT.BAS       (05-01-99)
'               : Set a picture upside down with movement of data in
'                 an integer GET-array.
'which basic    : PowerBASIC and - with remout $huge - Q(uick)BASIC
'auteur         : Jacob Wieles
$huge           'a must for PowerBASIC 3.5
defint a-z
screen 12
xL=0
xR=311
yT=0
yB=419
x=xR-xL+1
y=yB-yT+1
locate 2,1
print" xL = 0  xR = 311"
print" yT = 0  yB = 419"
print
print" x = xR-xL+1 =";x
print" y = yB-yT+1 =";y
locate 10,1
print" because x is a"
print" multiple of eight :"
print" reqsize = 2+x/8*2*y"
print
print" line(xL,yT)-(xR,yB),10,b"
print" line(xL+x/2,0)-(xR,yB),10"
print
print" dim scrnarr(reqsize-1)."
print" get (xL,yT)-(xR,yB),scrnarr"
reqsize=2+x/8*2*y
dim scrnarr(reqsize-1)
line(xL,yT)-(xR,yB),10,b
line(xL+x/2,0)-(xR,yB),10
get (xL,yT)-(xR,yB),scrnarr
locate 20,2
color 10
while inkey$<>"":wend
print"Hit a key for next."
hitakey$=input$(1)
cls
color 14
locate 2,1
print"  Hit a key for the 'up side down' picture with :"
print
print"  epxl=x/8*2             'array elements per xline"
print
print"  for i=1 to y\2           'lines upper half change"
print"                           'with lines lower half"
print"    for j=0 to epxl-1"
print"      swap scrnarr(2+(i-1)*epxl+j), scrnarr(reqsize-i*epxl+j)"
print"    next j"
print"  next i"
print"  cls
print"  put (96,0),scrnarr
print
color 10
print"Notes:"
print
print"  x =";x,"y =";y
print
print"  array elements per xline =";x/8*2
print"  x-lines to change        =";y\2
print
print"  scrnarr(0) =";scrnarr(0)
print"  scrnarr(1) =";scrnarr(1)
while inkey$<>"":wend
hitakey$=input$(1)
cls
epxl=x/8*2                            'array elements per xline
for i=1 to y\2                        'lines upper half change
  for j=0 to epxl-1                   'with lines lower half
    swap scrnarr(2+(i-1)*epxl+j), scrnarr(reqsize-i*epxl+j)
  next j
next i
cls
put (96,0),scrnarr
color 12
locate 4,14
while inkey$<>"":wend
print"Hit a key for the end."
hitakey$=input$(1)
cls
screen 0
print"Hit a key for the source."