nxtbasic : screen scroll (text) in the foreground and bild2.raw on screen128 in the background

[funkheld]

hello, good day.
screen scroll (text) in the foreground and bild2.raw on screen128 in the background.

it's a great thing.

greetings

Code: Select all

SCREEN128
BVLOAD "bild2.raw" ,0,0

gosub ascii

HScroll=0
ScrollAmount = 1
StartEdit:
    Loop:
        Key$=GET
        if Key$="Q" then GOSUB links
	    if Key$="E" then GOSUB rechts
    Goto loop
end

links:
    if HScroll>ScrollAmount then
        HScroll=HScroll-ScrollAmount
        SLEEP 0
        POKEN $9F37,CHR$(HScroll MOD 256) + CHR$(HScroll/256) 
    end if
return

rechts:
    HScroll=HScroll+ScrollAmount
    SLEEP 0
    POKEN $9F37,CHR$(HScroll MOD 256) + CHR$(HScroll/256) 
return

ascii:
    line$ = SPC(256)    'this way 256 bytes are reservers, so no relocation of string space needed
    line$=""
    for i = 1 to 128
        'Build a string of 128 pairs of letter B CHR$(2) and a color byte CHR$(2)
        line$ = line$ + CHR$(3) + CHR$(4) 
    next
    
    'VPOKE a line at a time
    For d= 0 to GETROWS()-1
        VPOKEN 1,$b000 + (d*256),line$
    next d
return