Xjyuk

I'd like to draw a memory layout diagram in Tikz that looks a bit like the following:

Note that the original was an SVG file, and conversion to PNG causes the weird [Not supported by viewer] errors, not sure what that's about.

Anyway, how can I recreate that diagram in Tikz, but without the numbered stages, and with the sections starting at the very left?

I tried to modify this answer to near it to the posted image, but I don't know enough Tikz to get it quite there.

Something like this:

This is done using tikz but to hide the technicalities I have defined a macro MemoryLayout that accepts a coma separated list of x-coordinates/colours/labels so that the image above was produced by:

MemoryLayout
 12/blue!10/A,
 21/orange!20/B,
 30/red!30/C,
 39/yellow!30/D,
 48/green!30/E,
 62/white/relax

Use a label of relax when you do not want a label.

All that this macro does is loop over the input data to draw the picture using standard tikz commands. Here is the full code:

documentclass[tikz, border=5mm]standalone
usetikzlibrarydecorations.pathreplacing

newcommandMemoryLayout[1]
 begintikzpicture[scale=0.3]
 draw[thick](0,0)--++(0,3)node[above]$0$;
 foreach pt/col/lab [remember=pt as tp (initially 0)] in #1 
 foreach a in tp,...,pt-1 
 draw[fill=col](-a,0) rectangle ++(-1,2);
 
 draw[thick](-pt,0)--++(0,3)node[above]$pt$;
 iflabrelaxrelaxelse
 draw[thick,decorate, decoration=brace,amplitude=4mm]
 (-tp,-0.2)--node[below=4mm]lab (-pt,-0.2);
 fi
 
 endtikzpicture


begindocument

 MemoryLayout
 12/blue!10/A,
 21/orange!20/B,
 30/red!30/C,
 39/yellow!30/D,
 48/green!30/E,
 62/white/relax
 

enddocument

To remove the numbers just comment out the two draw[thick]...; commands.

Just for fun an implementation using only xcolor (and amstext for text in the labels below the brace). The memory command takes the following arguments:

memory[<width>]<num>[<height>]<color>[<label>]

<width>
: is the width of a single cell

<height>
: is the height of the cells

<color>
: is the colour used by the cells, it can contain an optional argument and a mandatory one, or just the mandatory one forwarded to textcolor, so both [gray].85 and white!85!black are valid.

<label>
: the text which is printed below the brace, if it is left out no brace will be drawn.

The borders' thickness is the current value of fboxrule, the rules don't add to the size of the cells. To draw more than a single block of memory, just put multiple memory instances after each other, make sure to not put a space in between. The size of the <label> might create white space, you'd have to take care for that.

documentclass[]article

usepackageamstext
usepackagexcolor

makeatletter
begingroup
lccode`A=`-
lccode`N=`N
lccode`V=`V
lowercaseendgroupdefmemory@novalANoValue-
longdefmemory@fiBgbfi#1#2fi
longdefmemory@fiTBbfi#1#2#3fi#2
newcommandmemory@ifnovalF[1]%>>=
 %
 ifxmemory@noval#1%
 memory@fiBgb
 fi
 @firstofone
 %=<<
newcommandmemory@ifnovalTF[1]%>>=
 %
 ifxmemory@noval#1%
 memory@fiTBb
 fi
 @secondoftwo
 %=<<
newcommandmemory@Oarg[2]%>>=
 %
 @ifnextchar[memory@Oarg@#2#2#1%
 %=<<
longdefmemory@Oarg@#1[#2]%>>=
 %
 #1#2%
 %=<<
newcommand*memory@oarg%>>=
 %
 memory@Oargmemory@noval
 %=<<
newcommand*memory@ifcoloropt%>>=
 %
 @ifnextchar[memory@ifcoloropt@truememory@ifcoloropt@false
 %=<<
longdefmemory@ifcoloropt@true#1memory@noval#2#3%>>=
 %
 #2%
 %=<<
longdefmemory@ifcoloropt@false#1memory@noval#2#3%>>=
 %
 #3%
 %=<<
newlengthmemory@width
newlengthmemory@height
setlengthmemory@width7pt
setlengthmemory@height10pt
newcountmemory@num
newcommand*memory@blocks[2]%>>=
 %
 memory@num#1relax
 fboxsep-fboxrule
 memory@ifcoloropt#2memory@noval
 defmemory@colortextcolor#2
 defmemory@colortextcolor#2%
 loop
 ifnummemory@num>0
 fboxmemory@colorrulememory@widthmemory@height%
 kern-fboxrule
 advancememory@numm@ne
 repeat
 %=<<
% memory:
% [#1]: width
% #2 : count
% [#3]: height
% #4 : colour
% [#5]: label
newcommand*memory%>>=
 %
 begingroup
 memory@oargmemory@a
 %=<<
newcommand*memory@a[2]%>>=
 %
 % #1 width
 % #2 count
 memory@ifnovalF#1memory@width#1relax%
 memory@Oargmemory@heightmemory@b#2%
 %=<<
newcommand*memory@b[3]%>>=
 %
 % #1 count
 % #2 height
 % #3 colour
 memory@ifnovalF#2memory@height#2relax%
 memory@oargmemory@c#1#3%
 %=<<
newcommand*memory@c[3]%>>=
 %
 % #1 count
 % #2 colour
 % #3 label
 memory@ifnovalTF#3
 ensuremathmemory@blocks#1#2
 ensuremathunderbracememory@blocks#1#2_text#3%
 endgroup
 %=<<
makeatother

begindocument
memory8orange%
memory8green[makebox[0pt][Not supported by viewer]]%
memory8yellow%
enddocument

% vim: fdm=marker fmr=>>=,=<<