Hi all,

I've been doing some testing to see if bytemaps can be overwritten as a way of reusing them and came up with the code below. The MPpage page 1 should, if my thinking is correct, give three unitsquares coloured red, blue, and green. However it seems the squares are all coloured green. To get what I expected I rewrote the code as in MPpage page 2, but to get the desired outcome I had to create 3 bytemaps. So, does this mean that bytemaps can't be overwritten, or am I missing something?

Best Wishes
Keith

\starttext
\startMPpage %page 1
color newColor;
newbytemap 1 of (250,250,3);
p := 0;
for i = 1 upto 3:
    for x := 0 upto 249:
        for y := 0 upto 249:
            if i = 1:
                newColor := \MPcolor{red};
            elseif i = 2:
                newColor := \MPcolor{blue};
            else:
                newColor := \MPcolor{green};
            fi;
            setbyte (x,y) of 1 to (newColor * 255);
        endfor;
    endfor;
    p := p + 259;
    fill
        unitsquare scaled 250 shifted(p - 259,0)
        withbytemap 1;
endfor;
\stopMPpage
\startMPpage%page 2
color newColor;
p := 0;
for i = 1 upto 3:
    newbytemap i of (250,250,3);
    for x := 0 upto 249:
        for y := 0 upto 249:
            if i = 1:
                newColor := \MPcolor{red};
            elseif i = 2:
                newColor := \MPcolor{blue};
            else:
                newColor := \MPcolor{green};
            fi;
            setbyte (x,y) of i to (newColor * 255);
        endfor;
    endfor;
    p := p + 259;
    fill
        unitsquare scaled 250 shifted(p - 259,0)
        withbytemap i;
endfor;
\stopMPpage
\stoptext
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