2018-02-21 18:27:00

1 files changed, 348 insertions, 357 deletions

diff --git a/tex/context/base/mkiv/page-sid.mkiv b/tex/context/base/mkiv/page-sid.mkiv
index 31c962719..a777efa32 100644
--- a/tex/context/base/mkiv/page-sid.mkiv
+++ b/tex/context/base/mkiv/page-sid.mkiv
@@ -18,16 +18,18 @@
 %D These macro deal with side floats. We started with Daniel Comenetz macros as
 %D published in TUGBoat Volume 14 (1993), No.\ 1: Anchored Figures at Either Margin.
 %D I extended and patched the macros to suite our needs which results in a messy
-%D module. Therefore, this module badly needs an update because it's now a mixture
-%D of old and new macros.
-
-% Interesting cases where it goes wrong:
-%
-% \placefigure[left]{}{} \dorecurse{3}{\input ward } {\par} \input ward
-
+%D module.
+%D
 %D A complication is that we need to deal with spacing differently before and after
-%D the float. Also, whitespace can interfere as does the prevdepth. There is no
-%D real universal solotion.
+%D the float. Also, whitespace can interfere as does the prevdepth. There is no real
+%D universal solution. So, by now not much is left of that code, if only because we
+%D need to match \CONTEXT\ spacing module, because we have more placement options
+%D and control and because the math hackery is not suitable for \CONTEXT\ anyway.
+%D
+%D This code had been redone many times because we kept running into spacing issues
+%D and it's not that much fun (or rewarding). It's probably the module that made
+%D me go into distraciton mode most often (like watching amusing Walk of The
+%D Earth or sophisticated Massive Attack video clips).
 
 \newdimen       \d_page_sides_height       % includes the topskip
 \newdimen       \d_page_sides_width
@@ -36,9 +38,8 @@
 \newdimen       \d_page_sides_vsize_reset
 \newdimen       \d_page_sides_progress
 \newdimen       \d_page_sides_page_total
-\newdimen       \d_page_sides_saved_depth
 
-\newbox         \b_page_sides_bottom
+%newbox         \b_page_sides_bottom
 
 \newcount       \c_page_sides_lines_done
 \newcount       \c_page_sides_checks_done
@@ -48,7 +49,6 @@
 
 \newconditional \c_page_sides_short
 \newconditional \c_page_sides_flag
-\newconditional \c_page_sides_dummy_lines
 
 \newdimen       \d_page_sides_shift
 \newdimen       \d_page_sides_extrashift
@@ -67,15 +67,35 @@
 \newdimen       \d_page_sides_toptotal
 \newdimen       \d_page_sides_bottomtotal
 
-\setnewconstant \c_page_sides_method   \plusone
-\setnewconstant \c_page_sides_align    \zerocount
-\setnewconstant \c_page_sides_skipmode \zerocount
-\setnewconstant \c_page_sides_tolerance\zerocount
+\newconstant    \c_page_sides_align
+\newconstant    \c_page_sides_skipmode
+\newconstant    \c_page_sides_tolerance
+
+\newconstant    \c_page_sides_method % sort of obsolete
+
+\newdimen       \d_page_sides_progression
+
+\newif          \iftracesidefloats % public (might change)
+
+%D Defaults:
 
 \d_page_sides_vsize_reset -\onepoint
 %d_page_sides_vsize_reset  \zeropoint % could be an option, needs testing
 
-\settrue\c_page_sides_dummy_lines     % when false gets reset to true afterwards
+%D We have some basic (and colorful) tracing:
+
+\def\page_sides_floats_legend
+  {\showmessage\m!floatblocks{16}\empty
+   \glet\page_sides_floats_legend\relax}
+
+\installtextracker{floats.anchoring}
+  {\page_sides_floats_legend
+   \tracesidefloatstrue}
+  {\tracesidefloatsfalse}
+
+%D The horizontal shifts depend on the location: left or right in the text, margin
+%D or edge. These shifts are rather stable and don't interfere with the page flow
+%D as much as the vertical ones do.
 
 \def\page_sides_process_float_backspace  {\global\c_page_sides_float_type\plusone  \page_sides_handle_float}
 \def\page_sides_process_float_leftedge   {\global\c_page_sides_float_type\plustwo  \page_sides_handle_float}
@@ -87,41 +107,14 @@
 \def\page_sides_process_float_cutspace   {\global\c_page_sides_float_type\pluseight\page_sides_handle_float}
 \def\page_sides_process_float_margin     {\global\c_page_sides_float_type\pluseight\page_sides_handle_float}
 
-\def\page_sides_check_skips
-  {\global\d_page_sides_toptotal   \dimexpr\d_page_sides_topskip   +\d_page_sides_topoffset   \relax
-   \global\d_page_sides_bottomtotal\dimexpr\d_page_sides_bottomskip+\d_page_sides_bottomoffset\relax
-   \ifcase\c_page_sides_skipmode
+\def\page_sides_check_horizontal_skips
+  {\ifcase\c_page_sides_skipmode
    \or % high
-     \global\d_page_sides_toptotal   \d_page_sides_topoffset
    \or % low
-     \global\d_page_sides_bottomtotal\d_page_sides_bottomoffset
    \or % fit
-     \global\d_page_sides_toptotal   \d_page_sides_topoffset
-     \global\d_page_sides_bottomtotal\d_page_sides_bottomoffset
-     \global\d_strc_floats_margin    \zeropoint
+     \global\d_strc_floats_margin\zeropoint
    \fi}
 
-\newif\iftracesidefloats % public (might change)
-
-\unexpanded\def\page_sides_force_depth
-  {\iftracesidefloats
-     \begingroup
-     \c_page_force_strut_depth_trace_mode\plusone
-     \forcestrutdepth
-     \endgroup
-   \else
-     \forcestrutdepth
-   \fi}
-
-\def\page_sides_floats_legend
-  {\writestatus\m!floatblocks{anchor: orange, shift: red, box: green, dummy: blue, depth: magenta}%
-   \glet\page_sides_floats_legend\relax}
-
-\installtextracker{floats.anchoring}
-  {\page_sides_floats_legend
-   \tracesidefloatstrue}
-  {\tracesidefloatsfalse}
-
 \def\page_sides_apply_horizontal_shift
   {\ifdim\d_page_sides_maximum>\zeropoint
      \ifcase\c_page_sides_float_type
@@ -221,12 +214,189 @@
        +\compensatedinnermakeupmargin
      \relax
    \fi
-   \ifdim\d_page_sides_rightskip>\zeropoint \global\advance\d_page_sides_rightskip\rightskip \fi
-   \ifdim\d_page_sides_leftskip >\zeropoint \global\advance\d_page_sides_leftskip \leftskip  \fi}
+   \ifdim\d_page_sides_rightskip>\zeropoint
+     \global\advance\d_page_sides_rightskip\rightskip
+   \fi
+   \ifdim\d_page_sides_leftskip >\zeropoint
+     \global\advance\d_page_sides_leftskip \leftskip
+   \fi}
+
+%D Shifts get applied to the float box:
+
+\def\page_sides_relocate_float#1%
+  {\global\setbox\floatbox\hpack
+     {\ifnum\c_page_sides_float_type=\plusfour
+        \kern\d_page_sides_leftshift
+      \else\ifnum\c_page_sides_float_type=\plusone
+        \kern\d_page_sides_leftshift
+      \fi\fi
+      \ifnum\c_page_sides_float_type>\plusfour
+        \kern-\d_page_sides_extrashift
+      \else
+        \kern\d_page_sides_shift
+      \fi
+      \vbox{#1\ifnum\c_page_sides_align=\plusfour \removedepth \fi}%
+      \ifnum\c_page_sides_float_type>\plusfour
+        \kern\d_page_sides_shift
+      \else
+        \kern-\d_page_sides_extrashift
+      \fi
+      \ifnum\c_page_sides_float_type=\pluseight
+        \kern\d_page_sides_rightshift
+      \else\ifnum\c_page_sides_float_type=\plusfive
+        \kern\d_page_sides_rightshift
+      \fi\fi}}
+
+%D The vertical skips are a nightmare and this mechanism is about as complex
+%D as one can get it.
+
+\def\page_sides_check_vertical_skips
+  {\ifdim\d_page_sides_topskip   <\zeropoint\d_page_sides_topskip   \zeropoint\fi
+   \ifdim\d_page_sides_bottomskip<\zeropoint\d_page_sides_bottomskip\zeropoint\fi
+   \ifdim\d_page_sides_midskip   <\zeropoint\d_page_sides_midskip   \zeropoint\fi
+   %
+   \global\d_page_sides_toptotal   \dimexpr\d_page_sides_topskip   +\d_page_sides_topoffset   \relax
+   \global\d_page_sides_bottomtotal\dimexpr\d_page_sides_bottomskip+\d_page_sides_bottomoffset\relax
+   \ifcase\c_page_sides_skipmode
+   \or % high
+     \global\d_page_sides_toptotal   \d_page_sides_topoffset
+   \or % low
+     \global\d_page_sides_bottomtotal\d_page_sides_bottomoffset
+   \or % fit
+     \global\d_page_sides_toptotal   \d_page_sides_topoffset
+     \global\d_page_sides_bottomtotal\d_page_sides_bottomoffset
+   \fi}
+
+%D These shifts get (selectively) applied with a bit of optional tracing.
+
+\def\page_sides_apply_vertical_shift_normal
+  {\global\setbox\floatbox\hpack % why extra box
+     {\vpack
+        {\forgetall
+         \hsize\wd\floatbox
+         \vskip\privatescratchdimen
+         \offinterlineskip
+         \box\floatbox
+         % somehow we need this \scratchbox magic, but at least it's the same as the
+         % tracer now
+         \setbox\scratchbox\emptybox
+         \wd\scratchbox\hsize
+         \ht\scratchbox\d_page_sides_bottomtotal
+         \box\scratchbox
+         \vskip-\d_page_sides_bottomtotal
+         \ifnum\c_page_sides_align=\plusfive
+           \vskip-\lineheight
+         \fi}}}
+
+\def\page_sides_apply_vertical_shift_traced
+  {\global\setbox\floatbox\hpack % why extra box
+     {\backgroundline[trace:r]{\ruledhpack{\vpack
+        {\forgetall
+         \hsize\wd\floatbox
+         \vskip\privatescratchdimen
+         \offinterlineskip
+         \backgroundline
+           [trace:g]%
+           {\ruledhpack{\box\floatbox}}%
+         \par
+         \blackrule
+           [\c!color=trace:s,%
+            \c!height=\d_page_sides_bottomtotal,%
+            \c!depth=\zeropoint,%
+            \c!width=\hsize]%
+         \vskip-\d_page_sides_bottomtotal
+         \ifnum\c_page_sides_align=\plusfive
+           \vskip-\lineheight
+         \fi}}}}}
+
+\def\page_sides_apply_vertical_shift
+  {\ifnum\c_page_sides_align=\plusfour
+     \getnoflines{\ht\floatbox}%
+     \privatescratchdimen\dimexpr\noflines\lineheight-\strutdp\relax
+     \getrawnoflines\d_page_sides_toptotal
+     \advance\privatescratchdimen\noflines\lineheight
+     \page_sides_force_depth
+     \ht\floatbox\privatescratchdimen
+     \dp\floatbox\zeropoint
+   \fi
+   \ifcase\c_page_sides_align \else
+     \global\d_page_sides_toptotal\zeropoint
+   \fi
+   \privatescratchdimen
+     \ifnum\c_page_sides_float_type<\plusfour
+       \d_page_sides_toptotal
+     \else\ifnum\c_page_sides_float_type>\plusfive
+       \d_page_sides_toptotal
+     \else
+       \zeropoint
+     \fi\fi
+   % the top of the box is at the previous baseline
+   \ifcase\c_page_sides_align
+       % 0 normal
+     \advance\privatescratchdimen\strutdp % or \openstrutdepth
+   \or % 1 height
+     \advance\privatescratchdimen\strutdp % or \openstrutdepth
+   \or % 2 line
+   \or % 3 depth
+     \advance\privatescratchdimen\lineheight % or \openlineheight
+     \advance\privatescratchdimen\strutdp    % or \openstrutdepth
+   \or % 4 grid
+     \privatescratchdimen\zeropoint
+   \or
+     \advance\privatescratchdimen\strutht % or \openstrutheight
+   \fi
+   % new
+   \global\c_page_sides_lines_done\zerocount
+   \ifnum\c_page_sides_n_of_lines>\zerocount
+     \advance\privatescratchdimen\c_page_sides_n_of_lines\lineheight
+   \fi
+   \iftracesidefloats
+     \page_sides_apply_vertical_shift_traced % uses \privatescratchdimen
+   \else
+     \page_sides_apply_vertical_shift_normal % uses \privatescratchdimen
+   \fi
+   \ifnum\c_page_sides_float_type<\plusfour
+     \global\d_page_sides_toptotal\zeropoint
+   \else\ifnum\c_page_sides_float_type>\plusfive
+     \global\d_page_sides_toptotal\zeropoint
+   \fi\fi
+   \global\d_page_sides_downshift\zeropoint}
+
+%D We have a few virtual dimensions. I'm not sure what to do with \type
+%D {\pagedepth} and \type {\pageshrink} in the next two. If we ever need
+%D that it will become options.
+
+\def\e_page_sides_flush_criterium
+  {\dimexpr
+      \d_page_sides_vsize
+     -\d_page_sides_bottomtotal
+     -\pagetotal
+   \relax}
+
+\def\e_page_sides_room_criterium
+  {\dimexpr
+      \d_page_sides_vsize
+     -\d_page_sides_bottomtotal % added here too
+     -\pagetotal
+   \relax}
+
+%D In order to get a consistent spacing we force a strutdepth unless the
+%D preceding material has more depth than that already. This way anchoring
+%D becomes predictable.
+
+\unexpanded\def\page_sides_force_depth
+  {\iftracesidefloats
+     \begingroup
+     \c_page_force_strut_depth_trace_mode\plusone
+     \forcestrutdepth
+     \endgroup
+   \else
+     \forcestrutdepth
+   \fi}
 
 \def\page_sides_flush_floats
   {\par
-   \ifdim\dimexpr\d_page_sides_vsize-\d_page_sides_bottomtotal-\pagetotal\relax>\zeropoint % -\pagedepth
+   \ifdim\e_page_sides_flush_criterium>\zeropoint
      \page_sides_flush_floats_progress
      \page_sides_flush_floats_after_next
    \fi
@@ -234,14 +404,8 @@
 
 \def\page_sides_flush_floats_text
   {\par
-   \ifdim\dimexpr
-     \d_page_sides_vsize
-% no longer with the adapted skipper
-%     \ifnum\c_anch_backgrounds_text_level>\plusone
-       -\d_page_sides_bottomtotal
-%     \fi
-       -\pagetotal
-        \relax>\zeropoint % -\pagedepth
+   % what with \c_anch_backgrounds_text_level>\plusone
+   \ifdim\e_page_sides_flush_criterium>\zeropoint
      \page_sides_flush_floats_progress
      \page_sides_flush_floats_after_none
    \fi
@@ -254,9 +418,25 @@
    \global\setfalse\c_page_sides_flag
    \global\c_page_sides_checks_done\zerocount}
 
+\def\page_sides_flush_floats_after_none % we force a flush
+  {\ifdim\d_page_sides_midskip>\zeropoint
+      \blank[\the\d_page_sides_midskip]
+   \fi
+   \ignoreparskip
+   \blank[\v!disable]}
+
+\def\page_sides_flush_floats_after_next % we have two successive ones
+  {\ifdim\d_page_sides_bottomskip>\zeropoint
+      \blank[\the\d_page_sides_bottomskip]
+   \fi
+   \ignoreparskip
+   \blank[\v!disable]}
+
+%D A rudimentary checker:
+
 \unexpanded\def\doifelsesidefloat
   {\par
-   \ifdim\dimexpr\d_page_sides_vsize-\pagetotal\relax>\zeropoint % -\pagedepth
+   \ifdim\e_page_sides_room_criterium>\zeropoint % -\pagedepth
      \expandafter\firstoftwoarguments
    \else
      \expandafter\secondoftwoarguments
@@ -264,6 +444,10 @@
 
 \let\doifsidefloatelse\doifelsesidefloat
 
+%D Sometimes we need to fill up the space alongside a side float and this
+%D is where we define the helpers. A user can enforce a smaller step. We use
+%D large steps when possible.
+
 \installcorenamespace{sidefloatsteps}
 
 \setvalue{\??sidefloatsteps\v!line  }{\strut}
@@ -271,8 +455,6 @@
 \setvalue{\??sidefloatsteps\v!medium}{\halflinestrut} % was \halfstrut
 \setvalue{\??sidefloatsteps\v!small }{\noheightstrut} % was \quarterstrut
 
-% we don't officially know what kind of float we flush
-
 \def\page_sides_flush_floats_tracer
   {\dontleavehmode
    \ruledhpack\bgroup\backgroundline[trace:b]{%
@@ -296,6 +478,7 @@
 \def\page_sides_flush_floats_progress
   {\begingroup
    \page_sides_force_depth
+   \parskip\zeropoint
    \let\page_sides_flush_floats\relax
    \edef\m_pages_strut
      {\ifcsname\??sidefloatsteps\rootfloatparameter\c!step\endcsname
@@ -306,13 +489,8 @@
    \forgetall
    \offinterlineskip
    \doloop
-     {\scratchdimen\dimexpr
-         \d_page_sides_vsize
-        -\d_page_sides_bottomtotal
-        -\pagetotal
-      % -\pagedepth
-      \relax
-      \ifdim\scratchdimen>\onepoint % good enough, if we change it it will become a threshold
+     {\scratchdimen\e_page_sides_flush_criterium
+      \ifdim\scratchdimen>\onepoint      % good enough, can become configurable
         \ifnum\recurselevel>\plushundred % safeguard, sort of deadcycles
           \exitloop
         \else\iftracesidefloats
@@ -324,17 +502,55 @@
         \page_sides_force_depth
         \exitloop
       \fi}%
-   \global\setfalse\c_page_sides_dummy_lines
    \endgroup}
 
+%D We force a parskip and ignore it afterwards. We can nil it by setting the
+%D \type {spacebeforeside} parameter. We can have a leading blank so we need
+%D to make sure that we use blank to inject the parskip and then ignore
+%D the one injected by the engine.
 
-\def\page_sides_flush_floats_after_none % we force a flush
-  {\checkedblank[\rootfloatparameter\c!sidespaceafter]%
-   \page_sides_inject_after}
+\def\page_sides_inject_before
+  {\page_sides_force_depth
+   \ifdim\parskip>\zeropoint
+     \ifdim\parskip>\d_strc_floats_top
+       \ifdim\d_strc_floats_top>\zeropoint
+         \ignoreparskip
+         \blank[\v!white]%
+       \else
+         \checkedblank[\rootfloatparameter\c!spacebeforeside]%
+       \fi
+     \else
+       \checkedblank[\rootfloatparameter\c!spacebeforeside]%
+     \fi
+   \else
+     \checkedblank[\rootfloatparameter\c!spacebeforeside]%
+   \fi}
 
-\def\page_sides_flush_floats_after_next % we have two successive ones
-  {\checkedblank[\rootfloatparameter\c!sidespaceinbetween]% maybe also none
-   \page_sides_inject_after}
+%D We are now done with \type {spacebefore} and the parskip is already
+%D injected. The dummy line makes sure that we anchor properly and it
+%D also can serve as tracer.
+
+\def\page_sides_inject_dummy_line_normal
+  {\hpack to \availablehsize{\strut\hss}}
+
+\def\page_sides_inject_dummy_line_traced
+  {\ruledhpack to \availablehsize{\backgroundline[trace:c]{\page_sides_inject_dummy_line_normal}}}
+
+\def\page_sides_inject_dummy_lines
+  {\par
+   \nointerlineskip
+   \dontleavehmode
+   \iftracesidefloats
+     \page_sides_inject_dummy_line_traced
+   \else
+     \page_sides_inject_dummy_line_normal
+   \fi
+   \vskip-\dimexpr\lineheight+\strutdp\relax
+   \ignoreparskip
+   \blank[\v!samepage]
+   \blank[\v!disable]}
+
+%D Checkers:
 
 \def\page_sides_check_floats_after_par
   {\page_sides_check_floats_indeed
@@ -355,184 +571,23 @@
    \global\setfalse\c_page_sides_short
    \global\setfalse\c_page_sides_flag}
 
-\let\page_otr_sides_pop_penalties \relax
-\let\page_otr_sides_push_penalties\relax
-
-\def\page_sides_restore_output_penalty
-  {\ifnum\outputpenalty=\plustenthousand \else
-     \penalty\outputpenalty
-   \fi}
+%D Here comes the output routine. We either go the fast route or we use the
+%D normal one (stored in \type {\page_otr_command_side_float_output}. We no
+%D longer have this fuzzy code around with penalties and indentation and
+%D such.
 
 \def\page_sides_output_routine
-  {\ifconditional\c_page_sides_short
-     % Is this branch ever entered?
-     \page_sides_output_routine_yes
-   \else
-     \page_sides_output_routine_nop
-   \fi}
-
-\def\page_sides_output_routine_nop
-  {\page_otr_command_side_float_output % otr specific
-   \global\d_page_sides_vsize\d_page_sides_vsize_reset
-   \global\c_page_sides_n_of_lines\zerocount
-   % we can end up in fig lock, so \global\holdinginserts\zerocount here too ?
-   \page_otr_sides_pop_penalties}
-
-\def\page_sides_output_routine_yes % we need to rework this ... add pagediscards and such
-  {\unvbox\normalpagebox % bah, and the discards?
-   \setbox\b_page_sides_bottom\lastbox
-   \ifvoid\b_page_sides_bottom
-     % go on
-   \else\ifdim\wd\b_page_sides_bottom>\d_page_sides_hsize
-     % hm, i really need to write this from scratch
-     \penalty-201
-     \box\b_page_sides_bottom
+  {\page_otr_command_side_float_output
+   \ifconditional\c_page_sides_short
+     \global\setfalse\c_page_sides_short
    \else
-     \page_sides_restore_left_indent
-     \ifdim\wd\b_page_sides_bottom<\d_page_sides_hsize
-       \parskip\zeropoint
-       %\noindent
-       \ifinner\else
-         \vadjust{\penalty\minusone}%
-       \fi
-       \global\advance\d_page_sides_hsize -\wd\b_page_sides_bottom
-       \global\divide\d_page_sides_hsize \plustwo
-       \hskip\d_page_sides_hsize % \kern
-     \fi
-     \box\b_page_sides_bottom
-     \page_sides_restore_output_penalty
-   \fi\fi
-   % why was this \global\holdinginserts\zerocount
-   \global\setfalse\c_page_sides_short}
-
-\def\page_sides_restore_left_indent
-  {\relax
-   \ifnum\c_page_sides_float_type>\plusfour \else
-     \parskip\zeropoint % here ?
-     \ifdim\d_page_sides_width>\zeropoint % new, see prikkels
-       \noindent
-       \ifinner \else
-         \vadjust{\penalty\minusone}%
-       \fi
-       \hskip\d_page_sides_width\relax % \kern
-    %\else
-    %  we have a margin or edge float
-     \fi
+     \global\d_page_sides_vsize\d_page_sides_vsize_reset
+     \global\c_page_sides_n_of_lines\zerocount
    \fi}
 
-\def\page_sides_relocate_float#1%
-  {\global\setbox\floatbox\hpack
-     {\ifnum\c_page_sides_float_type=\plusfour
-        \kern\d_page_sides_leftshift
-      \else\ifnum\c_page_sides_float_type=\plusone
-        \kern\d_page_sides_leftshift
-      \fi\fi
-      \ifnum\c_page_sides_float_type>\plusfour
-        \kern-\d_page_sides_extrashift
-      \else
-        \kern\d_page_sides_shift
-      \fi
-      \vbox{#1\ifnum\c_page_sides_align=\plusfour \removedepth \fi}%
-      \ifnum\c_page_sides_float_type>\plusfour
-        \kern\d_page_sides_shift
-      \else
-        \kern-\d_page_sides_extrashift
-      \fi
-      \ifnum\c_page_sides_float_type=\pluseight
-        \kern\d_page_sides_rightshift
-      \else\ifnum\c_page_sides_float_type=\plusfive
-        \kern\d_page_sides_rightshift
-      \fi\fi}}
-
-\def\page_sides_apply_vertical_shift_normal
-  {\global\setbox\floatbox\hpack % why extra box
-     {\vpack
-        {\forgetall
-         \hsize\wd\floatbox
-         \vskip\privatescratchdimen
-         \offinterlineskip
-         \box\floatbox
-         % somehow we need this \scratchbox magic, but at least it's the same as the
-         % tracer now
-         \setbox\scratchbox\emptybox
-         \wd\scratchbox\hsize
-         \ht\scratchbox\d_page_sides_bottomtotal
-         \box\scratchbox
-         \vskip-\d_page_sides_bottomtotal
-         \ifnum\c_page_sides_align=\plusfive \vskip-\lineheight \fi}}}
-
-\def\page_sides_apply_vertical_shift_traced
-  {\global\setbox\floatbox\hpack % why extra box
-     {\backgroundline[trace:r]{\ruledhpack{\vpack
-        {\forgetall
-         \hsize\wd\floatbox
-         \vskip\privatescratchdimen
-         \offinterlineskip
-         \backgroundline[trace:g]{\ruledhpack{\box\floatbox}}\par
-         \blackrule[\c!color=trace:s,\c!height=\d_page_sides_bottomtotal,\c!depth=\zeropoint,\c!width=\hsize]%
-         \vskip-\d_page_sides_bottomtotal
-         \ifnum\c_page_sides_align=\plusfive \vskip-\lineheight \fi}}}}}
-
-\def\page_sides_apply_vertical_shift
-  {\ifnum\c_page_sides_align=\plusfour
-     \getnoflines{\ht\floatbox}%
-     \privatescratchdimen\dimexpr\noflines\lineheight-\strutdp\relax
-     \getrawnoflines\d_page_sides_toptotal
-     \advance\privatescratchdimen\noflines\lineheight
-     % todo: maybe rounding problem here
-     % \global\setbox\floatbox\hbox{\lower\lineheight\box\floatbox}%
-     \page_sides_force_depth
-     \ht\floatbox\privatescratchdimen
-     \dp\floatbox\zeropoint
-   \fi
-   \ifcase\c_page_sides_align \else
-     \global\d_page_sides_toptotal\zeropoint
-   \fi
-   \privatescratchdimen
-     \ifnum\c_page_sides_float_type<\plusfour
-       \d_page_sides_toptotal
-     \else\ifnum\c_page_sides_float_type>\plusfive
-       \d_page_sides_toptotal
-     \else
-       \zeropoint
-     \fi\fi
-   % the top of the box is at the previous baseline
-   \ifcase\c_page_sides_align
-       % 0 normal
-     \advance\privatescratchdimen\strutdp % or \openstrutdepth
-   \or % 1 height
-     \advance\privatescratchdimen\strutdp % or \openstrutdepth
-   \or % 2 line
-   \or % 3 depth
-     \advance\privatescratchdimen\lineheight % or \openlineheight
-     \advance\privatescratchdimen\strutdp    % or \openstrutdepth
-   \or % 4 grid
-     \privatescratchdimen\zeropoint
-   \or
-     \advance\privatescratchdimen\strutht % or \openstrutheight
-   \fi
-   % new
-   \global\c_page_sides_lines_done\zerocount
-   \ifnum\c_page_sides_n_of_lines>\zerocount
-     \advance\privatescratchdimen\c_page_sides_n_of_lines\lineheight
-   \fi
-   \iftracesidefloats
-     \page_sides_apply_vertical_shift_traced % uses \privatescratchdimen
-   \else
-     \page_sides_apply_vertical_shift_normal % uses \privatescratchdimen
-   \fi
-   \ifnum\c_page_sides_float_type<\plusfour
-     \global\d_page_sides_toptotal\zeropoint
-   \else\ifnum\c_page_sides_float_type>\plusfive
-     \global\d_page_sides_toptotal\zeropoint
-   \fi\fi
-   \global\d_page_sides_downshift\zeropoint}
-
 \def\page_sides_place_float
   {\ifnum\c_page_sides_float_type=\plusfour \kern\d_page_sides_toptotal \fi
    \ifnum\c_page_sides_float_type=\plusfive \kern\d_page_sides_toptotal \fi
-%    \d_page_sides_saved_depth\prevdepth
-%    \nointerlineskip
    \ifgridsnapping
      \page_sides_place_float_grid
    \else
@@ -540,10 +595,8 @@
    \fi
    \par
    \kern-\d_page_sides_height
-\vskip-\parskip
    \penalty10001 % oeps, this will change
-   \normalbaselines
-}%   \prevdepth\d_page_sides_saved_depth}
+   \normalbaselines}
 
 \def\page_sides_place_float_normal
   {\page_sides_push_float_inline\firstofoneargument}
@@ -556,7 +609,7 @@
    \ifx\p_grid\empty\else
      \snaptogrid[\p_grid]%
    \fi
-   \hbox{#1}}
+   \hpack{#1}}
 
 \def\page_sides_place_float_grid
   {\getrawnoflines\d_page_sides_height % raw ?
@@ -625,7 +678,15 @@
    \scratchdimenone\d_page_sides_vsize
    \scratchdimentwo\pagegoal
    \ifcase\c_page_sides_tolerance
-     \advance\scratchdimentwo -\strutdp
+     \ifcase\c_page_sides_method
+       % method 0 : raw
+     \or
+       % method 1 : safe (default)
+       \advance\scratchdimentwo -\strutdp
+     \or
+       % method 2 : tight (grid default)
+       \advance\scratchdimenone -\onepoint
+     \fi
    \or
      % tolerant
      \advance\scratchdimentwo -.5\strutdp
@@ -634,14 +695,13 @@
    \else
      \advance\scratchdimentwo -\strutdp
    \fi
-   % here also pagedepth
+   % how about \pagedepth
    \ifdim\scratchdimenone>\scratchdimentwo
      \global\setfalse\c_page_floats_room
    \else
      \ifdim\dimexpr\pagegoal-\d_page_sides_vsize\relax<\d_page_sides_bottomtotal
       % just weird: \global\advance\d_page_sides_vsize \scratchdimenone
        \global\settrue\c_page_sides_short
-       \page_otr_sides_push_penalties
        % why was this \global\holdinginserts\plusone
      \else
        \global\advance\d_page_sides_vsize \d_page_sides_bottomtotal % wins over inbetween
@@ -650,25 +710,15 @@
      \global\settrue\c_page_floats_room
    \fi}
 
-\def\page_sides_inject_before
-  {\checkedblank[\rootfloatparameter\c!spacebeforeside]}
-
-% \def\page_sides_inject_after
-%   {\checkedblank[\rootfloatparameter\c!spaceafterside]}
-%
-% As we have no clear end of one or more paragraphs this makes no sense so:
-
-\let\page_sides_inject_after\donothing
-
-% \def\page_sides_prepare_space
-%   {\inhibitblank} % hm, why here .. gets obscured anyway
+%D As we have no clear end of one or more paragraphs we only have pre float
+%D skips.
 
 \def\page_sides_handle_float#1% grid (4) is rather experimental
-  {\page_sides_check_skips
-   \page_sides_inject_before
-%    \page_sides_prepare_space
+  {\page_sides_check_horizontal_skips
+   \page_sides_check_vertical_skips
    \page_sides_apply_horizontal_shift
    \page_sides_check_previous_float
+   \page_sides_inject_before
    \page_sides_inject_dummy_lines
    \page_sides_relocate_float{#1}%
    \page_sides_apply_vertical_shift
@@ -676,11 +726,18 @@
    \ifconditional\c_page_floats_room \else
      \page_otr_fill_and_eject_page
      \page_sides_analyse_space
+    %\page_sides_inject_before
      \page_sides_inject_dummy_lines
    \fi
    \page_sides_place_float
    \page_sides_check_floats_reset
-   \ignorespaces} % not really needed
+   \page_sides_wrapup}
+
+\def\page_sides_wrapup
+  {% we need to do this aftergroup
+   \ignoreparskip \aftergroup\ignoreparskip
+   \ignorespaces  \aftergroup\ignorespaces
+   }
 
 \def\page_sides_check_floats_indeed
   {\page_sides_analyse_progress
@@ -689,49 +746,27 @@
    \else
      \page_sides_check_floats_reset
    \fi
-   \parskip\s_spac_whitespace_parskip}
+   \parskip\s_spac_whitespace_parskip} % not needed
 
 \let\page_sides_check_floats\page_sides_check_floats_indeed
 
 \unexpanded\def\page_sides_check_floats_tracer
   {\begingroup
-   \hskip-\d_page_sides_width % kern
-  %\llap{\smallinfofont\the\d_page_sides_progression\space=>\space\the\c_page_sides_n_of_hang\hskip.5\leftmargindistance}%
-   \color[trace:o]%
-     {\vrule\s!height.5\points\s!depth.5\points\s!width\d_page_sides_width
-      \llap{\showstruts\strut\kern.25\bodyfontsize}}%
+   \dontleavehmode
+   \ifnum\c_page_sides_float_type>\plusfour
+     \rlap
+       {\hskip\availablehsize % d_page_sides_width % kern
+        \color[trace:o]%
+          {\rlap{\kern.25\bodyfontsize\showstruts\strut}%
+           \vrule\s!height.5\points\s!depth.5\points\s!width\d_page_sides_width}}%
+   \else
+     \hskip-\d_page_sides_width % kern
+     \color[trace:o]%
+       {\vrule\s!height.5\points\s!depth.5\points\s!width\d_page_sides_width
+        \llap{\showstruts\strut\kern.25\bodyfontsize}}%
+   \fi
    \endgroup}
 
-% \usemodule[art-01]
-% \starttext
-%     \definemeasure[MyHeight][3cm] \definemeasure[MyWidth][3cm]
-%     \startbuffer
-%         \input klein \par
-%         \placefigure[left]{oeps}{\framed[width=\measure{MyWidth},height=\measure{MyHeight}]{}}
-%         \dorecurse{4}{test\par} \dorecurse{3}{\input klein }\par
-%         \placefigure[left]{oeps}{\framed[width=\measure{MyWidth},height=\measure{MyHeight}]{}}
-%         \dorecurse{3}{\input klein }\par
-%     \stopbuffer
-%     \enabletrackers[floats.anchoring]
-%     \setupfloats[step=small]
-%     \setupheadertexts[width=\measure{MyWidth},height=\measure{MyHeight}]
-%     \dostepwiserecurse {100} {120} {1} {
-%         \definemeasure[MyWidth][#1pt]
-%         \dostepwiserecurse {50} {300} {1} {
-%             \definemeasure[MyHeight][##1pt]
-%             \setupwhitespace[none]%
-%             \getbuffer \page
-%             \setupwhitespace[big]
-%             \getbuffer \page
-%         }
-%     }
-% \stoptext
-
-% \setupfloats
-%   [\c!sidethreshold=.5\strutdp] % set to "old" to check with old method
-
-\newdimen\d_page_sides_progression
-
 \unexpanded\def\page_sides_check_floats_set
   {\edef\p_sidethreshold{\floatparameter\c!sidethreshold}%
    \ifx\p_sidethreshold\v!old
@@ -749,7 +784,6 @@
      \c_page_sides_n_of_hang\noflines
    \fi
    \ifnum\c_page_sides_n_of_hang>\zerocount
-     % new from here (needs test case, old code)
      \ifcase\c_page_sides_n_of_lines
      \else
        \ifcase\c_page_sides_lines_done
@@ -760,33 +794,28 @@
          \global\advance\c_page_sides_n_of_lines-\privatescratchcounter
        \fi
      \fi
-     % hm, when do we get the parshape branch? needs testing
      \ifnum\c_page_sides_n_of_lines>\zerocount
        \privatescratchtoks\emptytoks
        \privatescratchcounter\c_page_sides_n_of_lines
        \privatescratchdimen\dimexpr\hsize-\d_page_sides_width\relax
        \dorecurse\c_page_sides_n_of_lines
-        %{\appendtoks \zeropoint \hsize \to \privatescratchtoks}%
          {\toksapp\privatescratchtoks{\zeropoint\hsize}}%
        \ifnum\c_page_sides_n_of_hang>\c_page_sides_n_of_lines
          \advance\c_page_sides_n_of_hang -\c_page_sides_n_of_lines\relax
          \advance\privatescratchcounter\c_page_sides_n_of_hang
          \dorecurse\c_page_sides_n_of_hang % weird, shouldn't that be scratchcounter
            {\ifnum\c_page_sides_float_type>\plusfour
-             %\appendtoks \zeropoint         \privatescratchdimen \to \privatescratchtoks
               \toksapp\privatescratchtoks{\zeropoint\privatescratchdimen}%
             \else
-             %\appendtoks \d_page_sides_width\privatescratchdimen \to \privatescratchtoks
               \toksapp\privatescratchtoks{\d_page_sides_width\privatescratchdimen}%
             \fi}%
        \fi
        \parshape
          \numexpr\privatescratchcounter+\plusone\relax
-         \the\privatescratchtoks  % \privatescratchcounter
-         \zeropoint \hsize % \plusone
+         \the\privatescratchtoks
+         \zeropoint \hsize
        \relax
      \else
-       % new till here
        \hangindent \ifnum\c_page_sides_float_type>\plusfour -\fi\d_page_sides_width
        \hangafter-\c_page_sides_n_of_hang
      \fi
@@ -815,51 +844,13 @@
      \fi
    \fi}
 
-\def\page_sides_inject_dummy_line_normal
-  {\hpack to \availablehsize{\strut\hss}}
-
-\def\page_sides_inject_dummy_line_traced
-  {\ruledhpack to \availablehsize{\backgroundline[trace:b]{\page_sides_inject_dummy_line_normal}}}
-
-\def\page_sides_inject_dummy_lines % so always one
-  {\ifconditional\c_page_sides_dummy_lines
-     \par
-     \page_sides_force_depth
-    %\checkedblank[\rootfloatparameter\c!sidespacebefore]%
-     \begingroup
-     \privatescratchcounter\pageshrink
-     \divide\privatescratchcounter \lineheight % \baselineskip
-     \advance\privatescratchcounter\plusone
-     \offinterlineskip
-     \ifcase\privatescratchcounter\else
-       \dorecurse\privatescratchcounter
-         {\dontleavehmode
-          \iftracesidefloats
-            \page_sides_inject_dummy_line_traced
-          \else
-            \page_sides_inject_dummy_line_normal
-          \fi
-          \par}%
-     \vskip-\lineheight
-     \vskip-\strutdp
-%        \blank[-\v!line]%
-     \fi
-     \endgroup
-   \else\ifdim\d_page_sides_midskip>\zeropoint\else
-%      \vskip\parskip
-     \ifdim\parskip>\zeropoint
-       \blank[\v!white]%
-     \fi
-   \fi\fi
-   \global\settrue\c_page_sides_dummy_lines}
-
-\def\adjustsidefloatdisplaylines % public, will change
-  {\aftergroup\page_sides_adjust_display_lines}
-
-\def\page_sides_adjust_display_lines
-  {\par
-   \noindent
-   \ignorespaces}
+% \def\adjustsidefloatdisplaylines % public, will change
+%   {\aftergroup\page_sides_adjust_display_lines}
+%
+% \def\page_sides_adjust_display_lines
+%   {\par
+%    \noindent
+%    \ignorespaces}
 
 %D We need to hook it into the other otr's. This code will be adapted once we rename
 %D the callers. We use \type {\def} as they can be redefined! Some will become obsolete