%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Module: ZzTeX Float Facilities
%
% Synopsis: This module contains the float and caption blocks, as well as
% all the code required to support the scheduling of floats.
%
% Notes: The broadside capability was implemented by Richard A. Wells and
% integrated into ZzTeX on 9/7/94.
%
% Author: Richard A. Wells & Paul C. Anagnostopoulos
% Created: 7 March 1990
%
% Copyright 1989--2020 by Paul C. Anagnostopoulos
% under The MIT License (opensource.org/licenses/MIT)
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Data Structures
% ---- ----------
\definecount{\zfltcount}{0}
\def \zfloatfreeq {}
\def \zfloatpendq {}
\def \zdeffloat #1#2{% {\float}{\float-box}
\definebox{#2}%
\zfreefloat{#1}{#2}%
\global\increment \zfltcount}
\def \zgetfloat #1{% {\float}
\if \emptydefp{\zfloatfreeq}%
\error{toomanyflt}
{More than `\the\zfltcount' floats remain for page makeup}%
\else
\pop{#1}{\zfloatfreeq}%
\fi}
\def \zfreefloat #1#2{% {\float}{\float-box}
\gdef #1{\def \zcurfloatbox {#2}}%
\append{#1}{\zfloatfreeq}}
\zdeffloat{\zflta}{\zfltboxa}
\zdeffloat{\zfltb}{\zfltboxb}
\zdeffloat{\zfltc}{\zfltboxc}
\zdeffloat{\zfltd}{\zfltboxd}
\zdeffloat{\zflte}{\zfltboxe}
\zdeffloat{\zfltf}{\zfltboxf}
\zdeffloat{\zfltg}{\zfltboxg}
\zdeffloat{\zflth}{\zfltboxh}
\zdeffloat{\zflti}{\zfltboxi}
\zdeffloat{\zfltj}{\zfltboxj}
\zdeffloat{\zfltk}{\zfltboxk}
\zdeffloat{\zfltl}{\zfltboxl}
\zdeffloat{\zfltm}{\zfltboxm}
\zdeffloat{\zfltn}{\zfltboxn}
\zdeffloat{\zflto}{\zfltboxo}
\zdeffloat{\zfltp}{\zfltboxp}
\zdeffloat{\zfltq}{\zfltboxq}
\zdeffloat{\zfltr}{\zfltboxr}
\zdeffloat{\zflts}{\zfltboxs}
\zdeffloat{\zfltt}{\zfltboxt}
\zdeffloat{\zfltu}{\zfltboxu}
\zdeffloat{\zfltv}{\zfltboxv}
\zdeffloat{\zfltw}{\zfltboxw}
\zdeffloat{\zfltx}{\zfltboxx}
\zdeffloat{\zflty}{\zfltboxy}
\zdeffloat{\zfltz}{\zfltboxz}
% There is an insert class for each of the two places where floats
% can go.
\defineinsert{\ztopcolinsert} % Floats at top of column.
\count\ztopcolinsert = 1000
\dimen\ztopcolinsert = \maxdimen
\skip\ztopcolinsert = 0pt
\defineinsert{\zbotcolinsert} % Floats at bottom of column.
\count\zbotcolinsert = 1000
\dimen\zbotcolinsert = \maxdimen
\skip\zbotcolinsert = 0pt
% We need a dimension register to capture box depths.
\definedimen{\zfloatdp}{0pt}
% Float Types
% ----- -----
\setlist \zfloattypelist = {}
\def \definefloattype #1#2#3{% {type}{toc-level}{association}
\if \emptyargp{#3}%
\withname\definecount{\float#1number}{0}%
\withname\declaresnapitem{\float#1number}%
\else
\edef \znext {%
\global\withname\let{\float#1number}=\name{\float#3number}}%
\znext
\fi
\withname\gdef{\zflt#1lvl}{#2}%
\append{#1}{\zfloattypelist}}
\def \resetfloatnumbers {%
\maplist{\global\name{\float##1number}=0\relax}{\zfloattypelist}}
% Predefined float types (don't forget an index locator for each one).
\definefloattype{algorithm}{101}{}
\definefloattype{figure}{102}{}
\definefloattype{table}{103}{}
\definefloattype{listing}{104}{}
\definefloattype{sidebar}{105}{}
% Float Block
% ----- -----
\defineblock{\float}{\endfloat}{\false}{}
%~block float Type
% \aboveskip = glue % Space b/b above float.
% \def \beginformat {...} % Beginning of float formatter.
% \belowskip = glue % Space b/b below float.
% \def \comptextformat {...} % Composite number text formatter.
% \continue = integer % Continued or continuation.
% \def \endformat {...} % End of float formatter.
% \leftindent = dimen % Horizontal fudge for all floats.
% \pageplacement = {...} % Overriding page placement.
% \position = {...} % Position (see below).
% \runners = {style} % Runners for a page of floats.
% \topfloatfudge = dimen % Vertical fudge for topmost float.
% \width = dimen % Explicit width for float.
%~end
\definetoks{\pageplacement}
\definedimen{\topfloatfudge}{0pt}
% These derived parameters are needed here and by \caption. They may
% also be useful to the user.
\definecount{\floatpage}{0}
\definedimen{\floatshift}{0pt}
\definedimen{\floatwidth}{0pt}
\definecount{\zdivfltcounter}{0} % Count floats in each division.
\definebox{\zfltbroadbox}
% Floats are packaged up in a vbox using \vtop, so that the float box
% has the same height as the first thing inside. This improves the
% chances that a float at the top of a page will be positioned correctly.
\def \float #1{% {type}
\if \undefinedp{\float#1number}%
\error{undefflt}{Float type `#1' has not been defined}%
\fi
\endgraf
\blockcantbein{\float}{\float}%
\blockcantbein{\float}{\multicolumn}%
\beginblockscope{float}%
\global\increment \floatdepth
\global\increment \zdivfltcounter
\whichpage{\floatpage}{zF:\the\divisionname-\the\zdivfltcounter}%
\def \beginformat {}% %~default soft
\continue = 0 %~default with
\def \comptextformat {}% %~default soft
\setflag \continuation = \false % Deprecated
\def \endformat {}% %~default soft
\leftindent = 0pt %~default soft
\pageplacement = {}% %~default with
\runners = {normal}% %~default soft
\zoldrunners{\normalheader\normalfooter}%
\width = \naturalwidth %~default soft
\processdesign{\float}{#1}%
\zsetcontinue % Handle old \continuation.
\if \notp{\continuationp}\global\withname\increment{\float#1number}\fi
\global\withname\floatnumber{\float#1number}%
\setcomptext{\floatcomptext}%
\def \zcurflttype {#1}%
\edef \zcurfltlvl {\name{\zflt\zcurflttype lvl}}%
\parindent = 0pt
\parrag = 0pt
\parskip = 0pt
\zparsefltpos{\the\position}%
\if \notp{\emptytoksp{\pageplacement}}%
\zparsefltpagepos{\the\pageplacement}%
\fi
\if \zfltposhere
\penalty \breakallowed % Synchronize main list.
\zparsefltpos{\the\position}% % Recalculate global stuff.
\if \notp{\emptytoksp{\pageplacement}}
\zparsefltpagepos{\the\pageplacement}%
\fi
\fi
\zcalcfltparams
\zgetfloat{\zcurfloat}%
\zcurfloat
\global\setbox \zcurfloatbox = \vtop \bgroup
\zpushvcontext
\setindentation{0pt}{0pt}%
\settextwidth{\floatwidth}%
\settaginfo{\the\floatcomptext}{}% % Set tag info without title.
\setsubtagnumber{0}%
\beginformat}
\def \endfloat {%
\endgraf
\endformat
\global\zfloatdp = \prevdepth
\tagpageonly{\uniquetag{zF}{\the\zdivfltcounter}}%
\zpopvcontext
\egroup % \vtop
\expandafter\xdef \zcurfloat {%
\def \noexpand\zcurfloatid {\zcurflttype\space \the\floatnumber}%
\def \noexpand\zcurfloatbox {\zcurfloatbox}%
\zfloatdp = \the\zfloatdp
\aboveskip = \the\aboveskip
\belowskip = \the\belowskip
\leftindent = \the\leftindent
\position = {\the\position}%
\pageplacement = {\the\pageplacement}%
\runners = {\the\runners}%
\floatshift = \the\floatshift
\topfloatfudge = \the\topfloatfudge}%
\expandafter\append \zcurfloat{\zfloatpendq}%
\zschedulefloats{\znext}{\false}{\false}%
\if \gtrp{\znext}{99}%
\zfltpage{\zpenfloatpage}%
\fi
\global\decrement \floatdepth
\endblockscope{float}}
%~ This |\float| modifier forces an alone float.
\def \alonefloat {% %^modifier
\with{\pageplacement={\alone}}}
%~ This |\float| modifier forces a bottom float.
\def \bottomfloat {% %^modifier
\with{\pageplacement={\bottom}}}
%~ This |\float| modifier forces a broadside float.
\def \broadsidefloat {% %^modifier
\with{\pageplacement={\broadside}}}
%~ This |\float| modifier forces a here float.
\def \herefloat {% %^modifier
\with{\pageplacement={\here}}}
%~ This |\float| modifier forces a separate float.
\def \separatefloat {% %^modifier
\with{\pageplacement={\separate}}}
%~ This |\float| modifier allows the float to occupy the
%~ running head area. Any running head is deleted.
\def \userharea {% %^modifier
\with{\runners={blind}%
\advance \topfloatfudge by -\headerheight}}
\def \adjusttopfloatfudge #1{%
\global\advance \topfloatfudge by #1\relax}
\def \piggybackfloat {%
\edef \znext {\noexpand\global\noexpand\increment
\name{\float\zcurflttype number}}%
\znext
\edef \znext {\floatnumber = \name{\float\zcurflttype number}}%
\znext}
% Controlling Floats
% ----------- ------
% This macro is invoked at the beginning of each division.
\def \zfltdivinit {%
\global\zdivfltcounter = 0\relax}
\setflag \zschedflts = \true
\def \deferfloats #1{% {boolean}
\global\setflag \zschedflts = {\notp{#1}}}
% Scheduling Tools
% ---------- -----
% These counters keep track of the number of floats scheduled for the
% current page.
\definecount{\ztopcolfloats}{0} % Number of top column floats.
\definecount{\zbotcolfloats}{0} % Number of bottom column floats.
\definecount{\zfloatsinserted}{0} % Total number of floats.
\definetoks{\zfltrunners} % Runners for first float on page.
% This macro initializes for handling floats on a new page.
\def \zfloatinit {%
\global\setflag \zschedflts = \true
\global\ztopcolfloats = 0
\global\zbotcolfloats = 0
\zfltrunners = {}}
% These macros simply hide some of the details to make the \zsched*
% macros easier to read.
\def \ztallytopfloat {%
\if \orp{\notp{\zfltposmargonly}}{\posp{\ztopcolfloats}}%
\global\increment \ztopcolfloats
\fi}
\def \zforcenewpage{%
\global\zfloatsinserted = 101\relax}
\let \zquitscheding = \exitmaplist
\def \zsetfloattall{%
\zmakefloatalone
\setflag \zfloattall = \true
\tracepagemakeup{Float is too tall for column; positioning `alone'.}}
\def \zmakefloatalone{%
\setflag \zfltposalone = \true
\setflag \zfltposbottom = \false
\setflag \zfltposhereonly = \false
\setflag \zfltposhere = \false
\setflag \zfltposseparate = \false
\setflag \zfltpostop = \false}
\def \zmakefloattop{%
\setflag \zfltposalone = \false
\setflag \zfltposbottom = \false
\setflag \zfltposhereonly = \false
\setflag \zfltposhere = \false
\setflag \zfltposseparate = \false
\setflag \zfltpostop = \true}
% Float Scheduler
% ----- ---------
% return-count is a counter passed in by the caller that we should
% set at the end of \zschedulefloats to indicate how
% many floats were emitted during this call. A value
% greater than 99 indicates that a new page should be
% FORCED (e.g. for alone floats) by the output routine.
% during-output? is a flag indicating that the caller is
% part of the output routine.
% flushing? A flag indicating whether we are flushing floats.
\def \zschedulefloats #1#2#3{% {return-count}{during-output?}{flushing?}
\tracepagemakeup{[Scheduling \if #2floats during output%
\else float when encountered\fi.}%
\tracepagemakeup{Page total: \the\pagetotal; goal: \the\pagegoal.}%
% Reset our counter
\global\zfloatsinserted = 0
\if \zschedflts
\if \emptydefp{\zfloatpendq}%
\tracepagemakeup{There are no floats to be scheduled.}%
\else
\endgraf
\zinitfloatfit{#2}%
{\setflag \zschedfirstseparate = \true
\setflag \zschedseparateloop = \false
\maplist{\zschedone{#2}{#3}{##1}}{\zfloatpendq}}%
\fi
\else
\tracepagemakeup{Floats are deferred now.}%
\fi
\tracepagemakeup{Float scheduling complete;
floats inserted: \the\zfloatsinserted.]}%
\xdef #1{\the\zfloatsinserted}}
\def \zschedone #1#2#3{% {during-output?}{flushing?}{\float}
#3%
\zparsefltpos{\the\position}%
\if \notp{\emptytoksp{\pageplacement}}
\zparsefltpagepos{\the\pageplacement}%
\fi
\if #2% % If flushing floats, force float
\setflag \zfltposbottom = \false % to a `separate'.
\setflag \zfltpostop = \false
\setflag \zfltposseparate = \true
\fi
\tracepagemakeup{Trying to schedule \zcurfloatid;
size: \the\ht\zcurfloatbox+\the\dp\zcurfloatbox.}%
\if \orp{\andp{\zfltposeven}{\oddpagep}}%
{\andp{\zfltposodd}{\evenpagep}}%
\tracepagemakeup{Float is deferred until appropriate even/odd page.}%
\zquitscheding
\else
\setflag \zfloatunsched = \true
\setflag \zfloattall = \false
% The following macros attempt, in order of priority, to schedule
% the current float. Each macro may set up state that causes
% the subsequent macro(s) to do nothing.
\zschedhereonly{#1}%
\zschedhere{#1}%
\zschedalone{#1}%
\zschedbroadside{#1}%
\zschedseparate{#1}%
\zschedtop{#1}%
\zschedbottom{#1}%
\if \zfloattall % Schedule as `alone'.
\zschedalone{#1}%
\fi
\if \zfloatunsched
\tracepagemakeup{Float could not be scheduled.}%
% This exits a \maplist call to \zschedone.
\zquitscheding
\else
% Remove the current float from the queue...
\pop{\zcurfloat}{\zfloatpendq}%
% ...and free up the associated data structures.
\expandaftertwice\zfreefloat \expandafter\zcurfloat\zcurfloatbox
\fi
\fi}
% Fitting a Float
% ------- - -----
% These registers are used in float fitting. They contain,
% respectively, the amount of vertical space used up by floats for
% the current page and the maximum space available for floats.
\definedimen{\zfloatpageused}{0pt}
\definedimen{\zfloatmaxavail}{0pt}
% Macro to initialize the above parameters (called in \zschedulefloats).
\def\zinitfloatfit #1{% {during-output?}
\if #1
\zfloatpageused = 0pt
% Effectively: zfloatmaxavail = (100-mintextpercent) * vsize
\calculate \tcounta = {100,-,\mintextpercent}%
\calculate \zfloatmaxavail = {\vsize,P,\tcounta}%
\else
% Effectively: zfloatpageused = max(pagetotal, vsize * mintextpercent)
\calculate \zfloatpageused = {\vsize,P,\mintextpercent,X,\pagetotal}%
\zfloatmaxavail = \pagegoal
\fi}
% The spacing above and below a float is fairly complicated.
% In this table, h is the height of the float, d is the depth.
%
% Position Sequence Above Below
%
% \alone only \topskip - h + none
% \topfloatfudge
% \bottom first \aboveskip - h none
% rest min(\aboveskip, none
% \belowskip) - h
%
% \separate first \topskip - h + none
% \topfloatfudge
% rest min(\aboveskip, none
% \belowskip) - h
% \top first \topskip - h + \belowskip - \topskip - d
% \topfloatfudge
% rest min(\aboveskip, \belowskip - \topskip - d
% \belowskip) - h
% Here and broadside floats are handled differently, below in \zfitfloathere
% and \zfitfloatbroadside
\def \zfitfloat #1#2#3#4#5{% {result-flag}{top?}{aboveskip-first}
% {aboveskip-rest}{belowskip}
{\if \zfltposmargonly
\tcounta = 0 % Margin float should act as first one.
\else
\tcounta = \if #2\ztopcolfloats \else \zbotcolfloats \fi
\fi
\zskipa = \if \zerop{\tcounta}#3\else #4\fi
\advance \zskipa by -\ht\zcurfloatbox
\if \andp{#2}{\zerop{\tcounta}}\advance \zskipa by \topfloatfudge \fi
\tdimena = \zskipa
\advance \tdimena by \ht\zcurfloatbox
\advance \tdimena by \dp\zcurfloatbox
\tdimenb = #5\advance \tdimena by \tdimenb
\tdimenc = \zfloatpageused
\if \notp{\zfltposmargonly}\advance \tdimenc by \tdimena \fi
\tracepagemakeup{Requires: \the\tdimena;
available: \the\zfloatmaxavail;
used: \the\zfloatpageused.}%
\if \dimlssp{\tdimenc}{\zfloatmaxavail}%
\if \andp{\notp{#2}}{\zfltposmargonly}%
\insert \zbotcolinsert {%
\vbox to 0pt{%
\vss
\moveright \floatshift \box\zcurfloatbox
\vskip -\dp\zcurfloatbox}}%
\else
\insert \if #2\ztopcolinsert \else \zbotcolinsert \fi {%
\vskip \zskipa
\moveright \floatshift \box\zcurfloatbox
\nobreak
\if \zfltposmargonly
\vskip \tdimenb
\nobreak
\vskip -\tdimena
\else
\vskip #5\relax
\fi}%
\fi
\if \emptytoksp{\zfltrunners}%
\global\zfltrunners = \expandafter{\the\runners}%
\fi
\global\increment \zfloatsinserted
\global\zfloatpageused = \tdimenc
\global\setflag #1= \true
\else
\global\setflag #1= \false
\fi}}
\def \zfitfloathere #1#2#3{% {result-flag}{aboveskip}{belowskip}
{\tdimena = #2\relax
\advance \tdimena by \dp\zcurfloatbox
\advance \tdimena by #3\relax
\tracepagemakeup{Requires: \the\tdimena;
page total: \the\pagetotal;
page goal: \the\pagegoal.}%
\advance \tdimena by \pagetotal
\if \dimlssp{\tdimena}{\pagegoal}%
\bbskipabove{\breaknever}{#2}%
\fakepar
\moveright \floatshift \box\zcurfloatbox
\prevdepth = \zfloatdp
\bbskipbelow{\breakallowed}{#3}%
\global\increment \zfloatsinserted
\global\setflag #1= \true
\else
\global\setflag #1= \false
\fi}}
\def \zfitfloatbroadside {%
{% We know there are no other floats on the the topcolumn when
% this is called (by \zschedbroadside only) and we don't have to
% worry about fixing up the vertical position at the end of the
% page.
%
% Compute the space required
% Start with the topskip
\tdimena = \topfloatfudge
% Add the *width* (since the box will be rotated)
\advance \tdimena by \wd\zcurfloatbox
\tracepagemakeup{Requires: \the\tdimena;
broadside floats always fit.}%
\insert \ztopcolinsert {%
% vskip the top float fudge
\vskip \topfloatfudge
% save the width for unskipping later
\tdimenb = \wd\zcurfloatbox
% vskip the *width* of the box to do the position translation
% that we can't do with PostScript
\vskip \tdimenb
% Put our hbox in a vbox, so we can "lower" it rather than move
% it right (since it will be rotated)
\global\setbox\zfltbroadbox = \vbox{%
\vskip\floatshift % replaces \moveright in other floats
\box\zcurfloatbox}%
\rotatebox{\zfltbroadbox}{90}%
% Undo vertical skip so that insert doesn't cause additional page
\vskip -\tdimenb}%
\if \emptytoksp{\zfltrunners}%
\global\zfltrunners = \expandafter{\the\runners}%
\fi
\global\increment \zfloatsinserted
\global\zfloatpageused = \tdimena}}
% Individual Schedulers
% ---------- ----------
% This is a temporary register used in calls to \zfitfloat where the
% fit needs to take into account more than one skip value (such as
% both the \aboveskip and \belowskip). In that case this dimen is
% used as a temp to hold the sum of the skip values.
\defineskip{\zfloatabove}{0pt}
\defineskip{\zfloatbelow}{0pt}
\definedimen{\zfloatextraskip}{0pt}
% This scheduler is called for floats with position `here' and no others.
\def\zschedhereonly #1{% {during-output?}
\if \andp{\zfloatunsched}{\zfltposhereonly}%
\tracepagemakeup{Float is to be positioned `here' only.}%
\if \zschedseparateloop
\tracepagemakeup{Making up a page of separates; quit.}%
\zforcenewpage
\zquitscheding
\else
\if #1% during output:
\tracepagemakeup{Float moved to top of this page.}%
\zmakefloattop
\else % when encountered:
\if \posp{\zbotcolfloats}%
\error{hereonlybot}{Cannot position float `here'; already floats
at bottom.}%
\else\if \dimzerop{\pagetotal}%
\tracepagemakeup{Float at top of column: schedule as `top' float.}%
\zmakefloattop
\else
\zfitfloathere{\zfloatfits}{\aboveskip}{\belowskip}%
\if \zfloatfits
\tracepagemakeup{Float inserted here.}%
\setflag \zfloatunsched = \false
\else
\tracepagemakeup{Float does not fit here.}%
\zforcenewpage
\zquitscheding
\fi
\fi\fi
\fi
\fi
\fi}
% This scheduler is called for floats with position `here' along with at
% least one other page position.
\def\zschedhere #1{% {during-output?}
\if \andp{\zfloatunsched}{\zfltposhere}%
\tracepagemakeup{Float can be positioned `here'.}%
\if \zschedseparateloop
\tracepagemakeup{Making up a page of separates; quit.}%
\zforcenewpage
\zquitscheding
\else
\if #1% during output:
\relax
\else % when encountered:
\if \posp{\zbotcolfloats}%
\tracepagemakeup{There are already floats positioned `bottom'.}%
\else\if \dimzerop{\pagetotal}%
\tracepagemakeup{Float at top of column: schedule as `top' float.}%
\zmakefloattop
\else
\zfitfloathere{\zfloatfits}{\aboveskip}{\belowskip}%
\if \zfloatfits
\tracepagemakeup{Float inserted here.}%
\setflag \zfloatunsched = \false
\else
\tracepagemakeup{Float does not fit here.}%
\fi
\fi\fi
\fi
\fi
\fi}
\def \zschedalone #1{% {during-output?}
\if \andp{\zfloatunsched}{\zfltposalone}%
\tracepagemakeup{Float can be positioned `alone'.}%
\if \zschedseparateloop
\tracepagemakeup{Making up a page of separates; quit.}%
\zforcenewpage
\zquitscheding
\else
\if \orp{#1}{\dimzerop{\pagetotal}}%
\if \firstcolumnp % building new page
\if \zerop{\zfloatsinserted}% no floats on this page, yet
\dp\zcurfloatbox = 0pt % Make it fit.
\zfitfloat{\zfloatfits}{\true}{\topskip}{999pt}{0pt}%
\if \zfloatfits
\ztallytopfloat
\tracepagemakeup{Inserted on a page by itself.}%
\zforcenewpage
\setflag \zfloatunsched = \false
\zquitscheding
\fi
\else % wait for next time
\tracepagemakeup{Already floats in this column; quit.}%
\zquitscheding
\fi
\else% still in the middle of a page
\tracepagemakeup{Not in first column of page; quit.}%
\zquitscheding
\fi
\else % As encountered, and page not empty.
\tracepagemakeup{Must wait for new page; quit.}%
\zquitscheding
\fi
\fi
\fi}
\def \zschedbroadside #1{% {during-output?}
\if \andp{\zfloatunsched}{\zfltposbroadside}%
\tracepagemakeup{Float can be positioned `broadside'.}%
\if \zschedseparateloop
\tracepagemakeup{Making up a page of separates; quit.}%
\zforcenewpage
\zquitscheding
\else
\if \orp{#1}{\dimzerop{\pagetotal}}%
\if \firstcolumnp % building new page
\if \zerop{\zfloatsinserted}% no floats on this page, yet
% Broadside floats "always" fit. The output will have to be
% inspected.
\zfitfloatbroadside
\ztallytopfloat
\tracepagemakeup{Inserted on a page by itself.}%
\zforcenewpage
\setflag \zfloatunsched = \false
\zquitscheding
\else % wait for next time
\tracepagemakeup{Already floats on this page; quit.}%
\zquitscheding
\fi
\else% still in the middle of a page
\tracepagemakeup{Not in first column of page; quit.}%
\zquitscheding
\fi
\else % As encountered, and page not empty.
\tracepagemakeup{Must wait for new page; quit.}%
\zquitscheding
\fi
\fi
\fi}
\def\zschedseparate #1{% {during-output?}
\if \andp{\zfloatunsched}{\zfltposseparate}%
\tracepagemakeup{Float can be positioned `separate'.}%
% If a separate float is called when encountered, we don't do anything.
\if #1% during output
\if \firstcolumnp % building a new page
\if \zschedfirstseparate
\if \zerop{\zfloatsinserted}% no floats on this page, yet
\zfloatmaxavail = \vsize % Entire page is available now.
\zfitfloat{\zfloatfits}{\true}{\topskip}{999pt}{0pt}%
\if \zfloatfits
\ztallytopfloat
\setflag \zfloatunsched = \false
\zforcenewpage % This is a page of separates now.
\tracepagemakeup{Inserted at the top of a new page.}%
\setflag \zschedfirstseparate = \false
\setflag \zschedseparateloop = \true
\else
\zsetfloattall
\fi
\else % wait for next time
\tracepagemakeup{Page already has other floats on it.}%
\zquitscheding
\fi
\else % Subsequent separates.
\zfloatabove = \if \dimlssp{\aboveskip}{\belowskip}\aboveskip
\else \belowskip \fi
\zfitfloat{\zfloatfits}{\true}{999pt}{\zfloatabove}{0pt}%
\if \zfloatfits
\ztallytopfloat
\setflag \zfloatunsched = \false
\tracepagemakeup{Inserted on a page with other separates.}%
\else
\zquitscheding
\tracepagemakeup{Does not fit on this page; start new page.}%
\fi
\fi
\else% still in the middle of a page
\tracepagemakeup{Must wait for new page; quit;}%
\zquitscheding
\fi
\else% when encountered
\tracepagemakeup{Must wait for new page; quit.}%
\zquitscheding
\fi
\fi}
\def\zschedtop#1{% {during-output?}
\if \andp{\andp{\zfloatunsched}{\zfltpostop}}
{\orp{\notp{\zfltposfollow}}{#1}}%
\tracepagemakeup{Float can be positioned `top'.}%
\if \zschedseparateloop
\tracepagemakeup{Making up a page of separates; quit.}%
\zforcenewpage
\zquitscheding
\else
\if \lssp{\ztopcolfloats}{\maxtopcolumnfloats}%
\zfloatabove = \if \dimlssp{\aboveskip}{\belowskip}\aboveskip
\else \belowskip \fi
\advance \zfloatabove by -\belowskip
\advance \zfloatabove by \topskip
\zfloatbelow = \belowskip
\tdimena = \topskip
\advance \zfloatbelow by -\tdimena
\advance \zfloatbelow by -\zfloatdp
\zfitfloat{\zfloatfits}{\true}{\topskip}{\zfloatabove}{\zfloatbelow}%
\if \zfloatfits
\ztallytopfloat
\tracepagemakeup{Inserted at top of column.}%
\setflag \zfloatunsched = \false
\else
\if \andp{#1}{\zerop{\zfloatsinserted}}\zsetfloattall \fi
\fi
\fi
\fi
\fi}
\def \zschedbottom#1{% {during-output?}
\if \andp{\zfloatunsched}{\zfltposbottom}%
\tracepagemakeup{Float can be positioned `bottom'.}%
\if \zschedseparateloop
\tracepagemakeup{Making up a page of separates; quit.}%
\zforcenewpage
\zquitscheding
\else
\if \lssp{\zbotcolfloats}{\maxbottomcolumnfloats}%
\zfloatbelow = \if \dimlssp{\aboveskip}{\belowskip}\aboveskip
\else \belowskip \fi
\zfitfloat{\zfloatfits}{\false}{\aboveskip}{\zfloatbelow}{0pt}%
\if \zfloatfits
\if \notp{\zfltpostopafterbot}%
\global\ztopcolfloats = \maxtopcolumnfloats
\fi
\global\increment \zbotcolfloats
\tracepagemakeup{Inserted at bottom of column.}%
\setflag \zfloatunsched = \false
\else
\if \andp{#1}{\zerop{\zfloatsinserted}}\zsetfloattall \fi
\fi
\fi
\fi
\fi}
% Captions
% --------
\defineblock{\caption}{\endcaption}{\false}{}
%~block caption Type
% \aboveskip = glue % Space b/b above caption.
% \setflag \allowintoc = flag % Allow caption in ToC.
% \belowskip = glue % Space b/b below caption.
% \captionfudge = dimen % Fudge for \aboveskip.
% \def \comptextformat {...} % (No longer used with captions.)
% \difficulty = integer % Level of difficulty.
% \leftindent = glue % Left indentation.
% \legendfont = {...} % Font for optional legend.
% \def \legendformat ##1{...} % Legend formatter.
% \numberfont = {...} % Font for float number.
% \parindent = dimen % Paragraph indent.
% \parrag = dimen % Paragraph raggedness.
% \parskip = glue % Paragraph skip.
% \position = {...} % Position (see below).
% \rightindent = glue % Right indentation.
% \style = {...} % Heading style.
% \titlefont = {...} % Font for caption title.
% \def \titleformat ##1{...} % Title formatter.
% \width = dimen % Width of caption text.
%~end
\definedimen{\captionfudge}{0pt}
\definetoks{\legendfont}
\definebox{\zcapbox}
\definedimen{\zcapshift}{0pt}
%~ This marker indicates that the following text is the legend or
%~ credit for the caption.
\definemarker{\legend}
\def \caption #1{% {title with optional \legend}
\blockmustbein{\caption}{\float}%
\blockcantbein{\caption}{\caption}%
\beginblockscope{caption}%
\global\increment \captiondepth
\captionfudge = 0pt %~default with
\def \comptextformat {}% %~default hard
\style = {Initial cap/lowercase}% %~default soft
\difficulty = 0 %~default with
\processdesign{\caption}{\zcurflttype}%
\global\increment \captionnumber
\if \notp{\emptydefp{\comptextformat}}%
\error{capcomptext}{The \string\comptextformat\space parameter is no
longer used in captions}
\fi
\captionformat #1\legend\zmark
\if \andp{\allowintoc}{\notp{\continuationp}}\zcaptoc #1\legend\zmark \fi
\endcaption
\zcaptag #1\legend\zmark}% % Reset tag info with title.
\def \endcaption {%
\global\decrement \captiondepth
\endblockscope{caption}}
\def \captionformat #1\legend#2\zmark{%
\the\numberfont
\setbox\zcapbox = \vtop{%
\zpushvcontext
\setindentation{\leftindent}{\rightindent}%
\settextwidth{\width}%
\setparrag{\parrag}%
\if \emptyargp{#2}%
\titleformat{#1}%
\else
\let \legend = \relax % So it won't interfere with formatting.
\titleformat{#1\the\legendfont \legendformat{#2}}%
\fi
\endgraf
\global\zfloatdp = \prevdepth
\zpopvcontext}%
\zparsecappos{\the\position}%
\zcalccapitems
\bbskipabove{\breaknever}{\aboveskip}%
\noindent \kern \zcapshift \box\zcapbox \par
\prevdepth = \zfloatdp
\bbskipbelow{\breaknever}{\belowskip}}
\def \zcaptoc #1\legend#2\zmark{%
\tocentry{\the\floatcomptext}{#1}{\zcurfltlvl}}
\def \zcaptag #1\legend#2\zmark{%
\settaginfo{\the\floatcomptext}{#1}}
% Position Handling
% -------- --------
% This macro sets up variables that specify the position of a float,
% according to the \position design parameter:
%
% \alone Place float on a page by itself.
% \anypage Place float on any page.
% \any (synonym for \anypage)
% \bottom Place float at the bottom of a page.
% \broadside Place float broadside (alone, rotated 90 degrees).
% \evenpage Place float on an even page.
% \follow Float must follow its position in the text.
% \here Place float exactly where it appears.
% \ifevenpage Use next position only on even page.
% \ifoddpage Use next position only on odd page.
% \leftmargin Shift float to left margin.
% \margin Same as \leftmargin.
% \marginonly Float fits in the margin and does not occupy any
% vertical space on the page.
% \nofollow Float need not follow its position in the text.
% \oddpage Place float on an odd page.
% \outsidemargin Shift float to outside margin.
% \rightmargin Shift float to right margin.
% \separate Place float on a page with floats only.
% \textarea Leave float at left edge of text area.
% \text (synonym for \textarea)
% \top Place float at the top of a page.
% \topafterbottom Okay to schedule \top float after \bottom.
\definecount{\zfltposshift}{0}
\def \zparsefltpos #1{% {options...}
{\zclearfltpagepos
\global\setflag \zfltposmargonly = \false
\global\zfltposshift = 0\relax
\zsetupfltpageopts
\def \ifevenpage ##1{\if \evenp{\floatpage}##1\fi}%
\def \ifoddpage ##1{\if \oddp{\floatpage}##1\fi}%
\def \leftmargin {\global\zfltposshift=1\relax}%
\let \margin = \leftmargin
\def \marginonly {\global\setflag\zfltposmargonly=\true}%
\def \outsidemargin{\ifevenpage{\leftmargin}\ifoddpage{\rightmargin}}%
\def \rightmargin {\global\zfltposshift=2\relax}%
\def \textarea {\global\zfltposshift=0\relax}%
\let \text = \textarea
\global\floatpage = \floatpage
#1%
\global\setflag \zfltposhereonly = \zfltposhere
\global\setflag \zfltposok = \zfltposhere
\if \orp{\zfltposalone}
{\orp{\zfltposbottom}
{\orp{\zfltposbroadside}
{\orp{\zfltposseparate}
{\zfltpostop}}}}%
\global\setflag \zfltposhereonly = \false
\global\setflag \zfltposok = \true
\fi
\if \zfltposhereonly \setflag \zfltposhere = \false \fi
\if \notp{\zfltposok}%
\warning{nofloatpos}{No page position has been specified for a float}%
\global\setflag \zfltposalone = \true
\fi}}
\def \zparsefltpagepos #1{% {options...}
{\zclearfltpagepos
\zsetupfltpageopts
#1%
\global\setflag \zfltposhereonly = \zfltposhere
\if \orp{\zfltposalone}
{\orp{\zfltposbottom}{\orp{\zfltposseparate}{\zfltpostop}}}%
\global\setflag \zfltposhereonly = \false
\fi
\if \zfltposhereonly \global\setflag \zfltposhere = \false \fi}}
\def \zclearfltpagepos {%
\global\setflag \zfltposalone = \false
\global\setflag \zfltposbottom = \false
\global\setflag \zfltposbroadside = \false
\global\setflag \zfltposeven = \false
\global\setflag \zfltposfollow = \false
\global\setflag \zfltposhere = \false
\global\setflag \zfltposodd = \false
\global\setflag \zfltposseparate = \false
\global\setflag \zfltpostop = \false
\global\setflag \zfltpostopafterbot = \false}
\def \zsetupfltpageopts {%
\def \alone {\global\setflag\zfltposalone=\true}%
\def \anypage {\global\setflag\zfltposeven=\false
\global\setflag\zfltposodd=\false}%
\let \any = \anypage
\def \bottom {\global\setflag\zfltposbottom=\true}%
\def \broadside {\global\setflag\zfltposbroadside=\true}%
\def \evenpage {\global\setflag\zfltposeven=\true}%
\def \follow {\global\setflag\zfltposfollow=\true}%
\def \here {\global\setflag\zfltposhere=\true}%
\def \nofollow {\global\setflag\zfltposfollow=\false}%
\def \oddpage {\global\setflag\zfltposodd=\true}%
\def \separate {\global\setflag\zfltposseparate=\true}%
\def \top {\global\setflag\zfltpostop=\true}%
\def \topafterbottom {\global\setflag\zfltpostopafterbot=\true}}
\def \zcalcfltparams {%
\floatshift = 0pt\relax
% Set \floatshift
\ifcase \zfltposshift
\relax
\or
\floatshift = \if \evenp{\floatpage}-\evenlefttextmargin
\else -\oddlefttextmargin \fi \relax
\or
\floatshift = \textmeasure
\else
\zzerror{Invalid value for float `\string\zfltposshift'}%
\fi
\advance \floatshift by \leftindent
% Set \floatwidth. Default of \naturalwidth is handled differently
% for broadsides than for non-broadsides. If \width not default, use
% it without modification.
\if \dimeqlp{\width}{\naturalwidth}%
\if \zfltposbroadside
\floatwidth = \textareaheight \relax
\else
\floatwidth = \textmeasure \relax
\ifcase \zfltposshift
\relax
\or
\advance \floatwidth by -\floatshift
\or
\floatwidth = \if \evenp{\floatpage}\evenrighttextmargin
\else \oddrighttextmargin \fi \relax
\else
\zzerror{Invalid value for float `\string\zfltposshift'}%
\fi
\fi
\else
\floatwidth = \width \relax
\fi}
% This macro sets up variables that specify the position of a caption,
% according to the \position design parameter:
%
% \above Caption is placed above the figure.
% \below Caption is placed below the figure.
% \follow Caption follows left edge of float.
% \ifevenpage Use next position only on even page.
% \ifoddpage Use next position only on odd page.
% \leftmargin Force caption in left margin.
% \margin Same as \leftmargin
% \outsidemargin Shift caption to outside margin.
% \rightmargin Force caption in right margin.
% \rise Caption rises up from bottom of figure.
% \separate Caption is separate from figure.
% \sink Caption sinks down from top of figure.
% \textarea Force caption at left edge of text area.
% \text (synonym for \textarea)
% \textarearight Force caption at right edge of text area.
% \textright (synonym for \textarearight)
\definecount{\zcapposshift}{0}
\definecount{\zcapposvflow}{0}
\def \zparsecappos #1{% {options...}
{\global\setflag \zcapposabove = \true
\global\zcapposvflow = 0\relax
\global\zcapposshift = 0\relax
\def \above {\global\setflag\zcapposabove=\true}%
\def \below {\global\setflag\zcapposabove=\false}%
\def \follow {\global\zcapposshift=4\relax}%
\def \ifevenpage ##1{\if \evenp{\floatpage}##1\fi}%
\def \ifoddpage ##1{\if \oddp{\floatpage}##1\fi}%
\def \leftmargin {\global\zcapposshift=1\relax}%
\let \margin = \leftmargin
\def \outsidemargin {\ifevenpage{\leftmargin}\ifoddpage{\rightmargin}}%
\def \rightmargin {\global\zcapposshift=2\relax}%
\def \rise {\global\zcapposvflow=1\relax}%
\def \separate {\global\zcapposvflow=0\relax}%
\def \sink {\global\zcapposvflow=2\relax}%
\def \textarea {\global\zcapposshift=0\relax}%
\let \text = \textarea
\def \textarearight {\global\zcapposshift=3\relax}%
\let \textright = \textarearight
#1}}
\def \zcalccapitems {%
\ifcase \zcapposshift
\zcapshift = 0pt
\or
\zcapshift = \if \evenp{\floatpage}-\evenlefttextmargin
\else -\oddlefttextmargin \fi \relax
\or
\zcapshift = \textmeasure
\or
\zcapshift = \textmeasure
\advance \zcapshift by -\wd\zcapbox
\or
\zcapshift = \floatshift
\else
\zzerror{Invalid value for caption `\string\zcapposshift'}%
\fi
\advance \zcapshift by -\floatshift
% Captions in broadsides *always* follow, i.e. \zcapshift is 0pt
\if \zfltposbroadside
\zcapshift = 0pt\relax
\fi
\ifcase \zcapposvflow
\relax
\or
\forcenextbbskip
\aboveskip = -\dp\zcapbox
\advance \aboveskip by \zfloatdp
\advance \aboveskip by \captionfudge
\or
\advance \belowskip by -\dp\zcapbox
\advance \belowskip by -\captionfudge
\else
\zzerror{Invalid value for caption `\string\zcapposvflow'}%
\fi}