SPECTRA Advanced Graphics

[LCD]

This is the Function to calculate Attribute Address in Dual line mode.

Code:

function CalcAdrDualOffset(x as ubyte,y as ubyte)
    dim y1 as uinteger
    y1=(y&96)+((y&28)>>2)+((y&3)<<3)
    return $6000+x+(y1<<5)
end function

In Dual Byte Colour mode it will return ink colour. For Paper you must add 4096.

With this:

Code:

sub FillMem(mem as Uinteger,size as Uinteger,byt as Ubyte)
    asm
        ld h,(ix+5)
        ld l,(ix+4)
        ld d,h
        ld e,l
        inc de
        ld b,(ix+7)
        ld c,(ix+6)
        dec bc
        ld a,(ix+9)
        ld (hl),a
        ldir
    end asm
end sub

You can now make something like cooper bars:

Code:

    FillMem(4096+CalcAdrDualOffset(0,13),32,RGBto64Col(1,0,1))
    FillMem(4096+CalcAdrDualOffset(0,14),32,RGBto64Col(2,0,2))
    FillMem(4096+CalcAdrDualOffset(0,15),32,RGBto64Col(3,0,3))
    FillMem(4096+CalcAdrDualOffset(0,16),32,RGBto64Col(2,0,2))
    FillMem(4096+CalcAdrDualOffset(0,17),32,RGBto64Col(1,0,1))

And these are the core routines...