Handle multiple postcomputes.

[pspp] / doc / dev / tlo-file-format.texi

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@node SPSS TableLook File Formats
@appendix SPSS TableLook File Formats

SPSS has a concept called a TableLook to control the styling of pivot
tables in output.  SPSS 15 and earlier used @file{.tlo} files with a
special binary format to save TableLooks to disk; SPSS 16 and later
use @file{.stt} files in an XML format to save them.  Both formats
expose roughly the same features, although the older @file{.tlo}
format does have some features that @file{.stt} does not.

This appendix describes both formats.

@menu
* SPSS TableLook STT Format::
* SPSS TableLook TLO Format::
@end menu

@node SPSS TableLook STT Format
@section The @file{.stt} Format

The @file{.stt} file format is an XML file that contains a subset of
the SPV structure member format (@pxref{SPV Structure Member Format}).
Its root element is a @code{tableProperties} element (@pxref{SPV
Detail Legacy Properties}).

@node SPSS TableLook TLO Format
@section The @file{.tlo} Format

A @file{.tlo} file has a custom binary format.  This section describes
it using the syntax used previously for SPV binary members (@pxref{SPV
Light Detail Member Format}).  There is one new convention: TLO files
express colors as @code{int32} values in which the low 8 bits are the
red component, the next 8 bits are green, and next 8 bits are blue,
and the high bits are zeros.

TLO files support various features that SPV files do not.  PSPP
implements the SPV feature set, so it mostly ignores the added TLO
features.  The details of this mapping are explained below.

At the top level, a TLO file consists of five sections.  The first
four are always present and the last one is optional:

@example
TableLook =>
   PTTableLook[tl]
   PVSeparatorStyle[ss]
   PVCellStyle[cs]
   PVTextStyle[ts]
   V2Styles?
@end example

Each section is described below.

@menu
* PTTableLook in SPSS TLO Files::
* PVSeparatorStyle in SPSS TLO Files::
* PVCellStyle and PVTextStyle in SPSS TLO Files::
* V2Styles in SPSS TLO Files::
@end menu

@node PTTableLook in SPSS TLO Files
@subsection @code{PTTableLook}

@example
PTTableLook =>
   ff ff 00 00 "PTTableLook" (00|02)[version]
   int16[flags]
   00 00
   bool[nested-row-labels] 00
   bool[footnote-marker-subscripts] 00
   i54 i18
@end example

In PTTableLook, @code{version} is 00 or 02.  The only difference is
that version 00 lacks V2Styles (@pxref{V2Styles in SPSS TLO Files})
and that version 02 includes it.  Both TLO versions are seen in the
wild.

@code{flags} is a bit-mapped field.  Its bits have the following
meanings:

@table @asis
@item 0x2
If set to 1, hide empty rows and columns; otherwise, show them.

@item 0x4
If set to 1, use numeric footnote markers; otherwise, use alphabetic
footnote markers.

@item 0x8
If set to 1, print all layers; otherwise, print only the current
layer.

@item 0x10
If set to 1, scale the table to fit the page width; otherwise, break
it horizontally if necessary.

@item 0x20
If set to 1, scale the table to fit the page length; otherwise, break
it vertically if necessary.

@item 0x40
If set to 1, print each layer on a separate page (only if all layers
are being printed); otherwise, paginate layers naturally.

@item 0x80
If set to 1, print a continuation string at the top of a table that is
split between pages.

@item 0x100
If set to 1, print a continuation string at the bottom of a table that
is split between pages.
@end table

When @code{nested-row-labels} is 1, row dimension labels appear
nested; otherwise, they are put into the upper-left corner of the
pivot table.

When @code{footnote-marker-subscripts} is 1, footnote markers are
shown as subscripts; otherwise, they are shown as superscripts.

@node PVSeparatorStyle in SPSS TLO Files
@subsection @code{PVSeparatorStyle}

@example
PVSeparatorStyle =>
   ff ff 00 00 "PVSeparatorStyle" 00
   Separator*4[sep1]
   03 80 00
   Separator*4[sep2]

Separator =>
   case(
       00 00
     | 01 00 int32[color] int16[style] int16[width]
   )[type]
@end example

PVSeparatorStyle contains eight Separators, in two groups.  Each
Separator represents a border between pivot table elements.  TLO and
SPV files have the same concepts for borders.  @xref{SPV Light Member
Borders}, for the treatment of borders in SPV files.

A Separator's @code{type} is 00 if the border is not drawn, 01
otherwise.  For a border that is drawn, @code{color} is the color that
it is drawn in.  @code{style} and @code{width} have the following
meanings:

@table @asis
@item @code{style} = 0 and 0 @leq{} @code{width} @leq{} 3
An increasingly thick single line.  SPV files only have three line
thicknesses.  PSPP treats @code{width} 0 as a thin line, @code{width}
1 as a solid (normal width) line, and @code{width} 2 or 3 as a thick
line.

@item @code{style} = 1 and 0 @leq{} @code{width} @leq{} 1
A doubled line, composed of normal-width (0) or thick (1) lines.  SPV
files only have ``normal'' width double lines, so PSPP maps both
variants the same way.

@item @code{style} = 2
A dashed line.
@end table

The first group, @code{sep1}, represents the following borders within
the pivot table, by index:

@enumerate 0
@item Horizontal dimension rows
@item Vertical dimension rows
@item Horizontal category rows
@item Vertical category rows
@end enumerate

The second group, @code{sep2}, represents the following borders within
the pivot table, by index:

@enumerate 0
@item Horizontal dimension columns
@item Vertical dimension columns
@item Horizontal category columns
@item Vertical category columns
@end enumerate

@node PVCellStyle and PVTextStyle in SPSS TLO Files
@subsection @code{PVCellStyle} and @code{PVTextStyle}

@example
PVCellStyle =>
   ff ff 00 00 "PVCellStyle"
   AreaColor[title-color]

PVTextStyle =>
   ff ff 00 00 "PVTextStyle" 00
   AreaStyle[title-style] MostAreas*7[most-areas]

MostAreas =>
   06 80
   AreaColor[color] 08 80 00 AreaStyle[style]
@end example

These sections hold the styling and coloring for each of the 8 areas
in a pivot table.  They are conceptually similar to the area style
information in SPV light members (@pxref{SPV Light Member Areas}).

The styling and coloring for the title area is split between
PVCellStyle and PVTextStyle: the former holds @code{title-color}, the
latter holds @code{title-style}.  The style for the remaining 7 areas
is in @code{most-areas} in PVTextStyle, in the following order:
layers, corner, row labels, column labels, data, caption, and footer.

@example
AreaColor =>
   00 01 00 int32[color10] int32[color0] byte[shading] 00
@end example

AreaColor represents the background color of an area.  TLO files, but
not SPV files, describe backgrounds that are a shaded combination of
two colors: @code{shading} of 0 is pure @code{color0}, @code{shading}
of 10 is pure @code{color10}, and value in between mix pixels of the
two different colors in linear degree.  PSPP does not implement
shading, so for 1 @leq{} @code{shading} @leq{} 9 it interpolates RGB
values between colors to arrive at an intermediate shade.

@example
AreaStyle =>
   int16[valign] int16[halign] int16[decimal-offset]
   int16[left-margin] int16[right-margin] int16[top-margin] int16[bottom-margin]
   00 00 01 00
   int32[font-size] int16[stretch]
   00*2
   int32[rotation-angle]
   00*4
   int16[weight]
   00*2
   bool[italic] bool[underline] bool[strikethrough]
   int32[rtf-charset-number]
   byte[x]
   byte[font-name-len] byte*[font-name-len][font-name]
   int32[text-color]
   00*2
@end example

AreaStyle represents style properties of an area.

@code{valign} is 0 for top alignment, 1 for bottom alginment, 2 for
center.

@code{halign} is 0 for left alignment, 1 for right, 2 for center, 3
for mixed, 4 for decimal.  For decimal alignment,
@code{decimal-offset} is the offset of the decimal point in 20ths of a
point.

@code{left-margin}, @code{right-margin}, @code{top-margin}, and
@code{bottom-margin} are also measured in 20ths of a point.

@code{font-size} is negative 96ths of an inch, e.g. 9 point is -12 or
0xfffffff3.

@code{stretch} has something to do with font size or stretch.  The
usual value is 01 and values larger than that do weird things.  A
reader can safely ignore it.

@code{rotation-angle} is a font rotation angle.  A reader can safely
ignore it.

@code{weight} is 400 for a normal-weight font, 700 indicates bold.
(This is a Windows API convention.)

@code{italic} and @code{underline} have the obvious meanings.  So does
@code{strikethrough}, which PSPP ignores.

@code{rtf-charset-number} is a character set number from RTF.  A
reader can safely ignore it.

The meaning of @code{x} is unknown.  Values 12, 22, 31, and 32 have
been observed.

The @code{font-name} is the name of a font, such as @code{Arial}.
Only US-ASCII characters have been observed here.

@code{text-color} is the color of the text itself.

@node V2Styles in SPSS TLO Files
@subsection @code{V2Styles}

@example
V2Styles =>
   Separator*11[sep3]
   byte[continuation-len] byte*[continuation-len][continuation]
   int32[min-col-width] int32[max-col-width]
   int32[min-row-height] int32[max-row-height]
@end example

This final, optional, part of the TLO file format contains some
additional style information.  It begins with @code{sep3}, which
represents the following borders within the pivot table, by index:

@table @asis
@item 0
Title.
@item 1@dots{}4
Left, right, top, and bottom inner frame.
@item 5@dots{}8
Left, right, top, and bottom outer frame.
@item 9, 10
Left and top of data area.
@end table

When V2Styles is absent, the inner frame borders default to a solid
line and the others listed above to no line.

@code{continuation} is the string that goes at the top or bottom
of a table broken across pages.  When V2Styles is absent, the
default is @code{(Cont.)}.

@code{min-col-width} is the minimum width that a column will be
assigned automatically.  @code{max-col-width} is the maximum width
that a column will be assigned to accommodate a long column label.
@code{min-row-width} and @code{max-row-width} are a similar range for
the width of row labels.  All of these measurements are in points.
When V2Styles is absent, the defaults are 36 for @code{min-col-width} and
@code{min-row-height}, 72 for @code{max-col-width}, and 120 for
@code{max-row-height}.