H1: 2.000beta8

!subsections "Enhancements,Fixes,Incompatibilities"

H2: Enhancements

There are lots of new things in this version.
The general enhancements are:

!block sections
. Easier enumerated values
. Look improvements
. Style rationalisation
. More build_title control variables
. Miscellaneous things.
!endblock

The table enhancements are:

!block sections
. Easier column widths
. Heading/footing rows for tables
. Table positioning
. Table filtering and sorting
. Landscape tables
. Column alignment
. Cell attributes
. Spreadsheet calculations.
!endblock

The page formatting enhancements are:

!block sections
. Arbitrary page sizes
. Headers and footers
. Header/footer special tags
. Header/footer borders
. Page backgrounds
. Page layout variables
. Page control within a book.
!endblock

The configuration enhancements are:

!block sections
. FrameMaker templates are no longer required
. Event processing enhancements.
!endblock

Details are given below.

Note: For {{html}} and {{txt}} targets, this release is slightly faster
than the previous one. For {{mif}} (and {{ps}}), this release may be
slightly slower (as SDF templates, not FrameMaker ones, are
now used).


H3: Easier enumerated values

Enumerated values no longer need to be quoted.
In a set of name-value pairs, if an expression is a single word where:

* the first character is uppercase
* the remaining characters are lowercase

then the word is assumed to be an enemerated value and
it is automatically converted to a string. For example,
the following two lines are now equivalent:

E:   P1[align="Center"] My Title
E:   P1[align=Center] My Title


H3: Look improvements

The overall appearance (i.e. look) of an SDF document can be
controlled via the -k option or the OPT_LOOK variable.
SDF now supports the following looks:

* {{simple}} - the default look, useful for general documentation

* {{fancy}} - QSD-like look, but without any logos

* {{infomap}} - look based on Information Mapping[[tm]]

* {{overhead}} - look suitable for overhead transparencies.

Note: For backwards compatibility, {{plain}} is now an alias for
{{simple}}.

H3: Style rationalisation

SDF now supports the styles (i.e. document types) below.

!block table; groups
Style           Purpose
General:
document        a normal document
manual          a manual
paper           a technical paper
Administration:
admin           generic administration document
fax             a fascimile
memo            a memorandum
newslttr        a newsletter
minutes         minutes of a meeting
Miscellaneous:
listing         a source code listing
!endblock

The {{MAC:build_title}} macro is used to build the cover page
for the general styles.
The {{FILT:title}} filter is used to build the title block
for the administation styles.
The miscellaneous styles do not have a title.

Adding new styles for a look is now much easier than it
was previously. Furthermore, {{manual}} is now just another
style rather than a special mode.


H3: More build_title control variables

{{MAC:build_title}} now supports the following variable:

* {{DOC_COVER}} - the logical name of the cover page to use.

Supported DOC_COVER values and their meanings are given below:

!block table
Value       Meaning
original    SDF's original cover page layout
project     a cover page useful for project documentation
manual      the cover page used when OPT_STYLE is manual
paper       the cover page used when OPT_STYLE is paper
!endblock

The {{manual}} cover supports a new macro called {{DOC_OFFICES}},
i.e. if DOC_OFFICES is defined, its contents are appended after
the inside cover page.


H3: Miscellaneous things

The {{SDF What's Planned}} document and {{bugs.html}}
have been replaced by the {{DOC:SDF Bug Database}}.
In fact, the organisation of the documentation has
been improved quite a bit.

Any document can now be converted to a FrameMaker book, i.e.
it is no longer necessary to specially organise files in
order to create a FrameMaker book.

Tables of style {{columns}} (the default) now have
a thin line above group rows.

Tables can now be specified as list items by using the {{listitem}}
parameter of the {{FILT:table}} filter. The value is the logical
indent of the list (e.g. 1, 2, etc.). When generating HTML
which contains a table within a numbered list, the {{listitem}}
parameter is necessary in order to prevent the numbering from
resetting.

#The new {{MAC:continued}} macro can be used to continue a heading
#onto another page (as is standard practice within Information Mapping).

The new {{box}} filter can be used to place a box around one or
more lines of text.

The new {{center}} filter can be used to center a region of text.

The new paragraph attribute called {{wide}} can be used to
specify that a paragraph straddles the side-head area in addition
to the main text area. Likewise. class filters (e.g. terms, references, etc.)
now also support the {{wide}} attribute.

By default, SDF automatically generates an {{id}} attribute for
all headings in the table of contents. However, it is occasionally
necessary to disable this, particularly when the same heading
appears multiple times in a file.
The new paragraph attribute {{noid}} can be used to prevent an
{{id}} being generated for a paragraph.

The title for an administration-style document can now be changed
by either setting the DOC_TYPE variable or by using the new {{type}}
parameter to the {{FILT:title}} filter. For example, if you want
the title "Urgent Memo" rather than the default "MEMORANDUM" for
a memo, you can now do the following:

E:!init OPT_STYLE="memo"
E:!block title; type="Urgent Memo"
E:{{usual name-values pairs go here ...}}
E:!endblock

The {{FILT:title}} filter now also supports a {{format}} parameter
which can be used to tune the column widths, when necessary.

RTF can now be generated via FrameMaker by using the new {{sdf2fmrtf}}
alias, i.e. the command is (say):

E:   sdf -2fmrtf myfile.sdf

When RTF is generated via FrameMaker, Word's standard style names are
used, where possible. This makes it easier to import the RTF file
into an existing Word document.

Lists of tables and lists of figures can now be generated for normal
documents, i.e. it is no longer necessary to use a FrameMaker book
to build these lists.

The new variable {{TXT_MARGIN}} can be used to control the width
for {{txt}} output. Likewise, the new variable {{POD_MARGIN}} can
be used to control the width of tables for {{pod}} format.

The new {{bugtrack}} module can be used to build a simple
bug tracking system like SDF's bug database.

The new {{namevalues}} macro can be used to output a set of
name-value pairs for an object. The parameters are:

* the class name
* the object name
* a comma-separated list of attribute names.

For example:

E:!namevalues 'bugs'; 'sd0001'; 'Priority,Status,Type'

Finer control over object catalog formatting is now available
via the new {{style}} and {{headings}} attributes. {{style}}
is the table style to use. The default value is {{plain}}.
If {{headings}} is set, column headings are output.
(By default, they are not.)


H3: Easier column widths

SDF now supports {{dynamic}} column widths for paper documentation, i.e.
if a width is not specified for a column, then the column is
sized based on the text within it and the space available.
Proportional column widths are also supported.

The {{format}} attribute of the {{FILT:table}} filter is either:

* a single number, in which case each digit represents 10% of the
  width available to the table, or

* a comma-separated list of column width specifications.

Examples of the column width specifications now supported are given below.

!block table
Value       Meaning
30pt        an exact size (other supported units are cm, mm, " and in)
30%         a percentage of the size available
30          a percentage of the size available (% is implicit)
10-20       dynamic size between 10% and 20% of the total width
-20         dynamic size between 0% and 20% of the total width
10-         dynamic size between 10% and 100% of the total width
-           dynamic size between 0% and 100% of the total width
3*          3 units of the remaining space
*           same as 1*
!endblock

For example, in the table below, the second column will be
twice the size of the last column.

!block example
!block  table; format="20,2*,10,*"
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock
!endblock

The output is:

!block  table; format="20,2*,10,*"
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock

If a column is not given a size, the following rules are used:

^ The last unspecified column size is implicitly '*' (i.e. the rest),
  unless the {{narrow}} attribute is set, in which case the size
  is implicitly '-' (i.e. as much as needed).

+ The other unknown sizes are implicitly '-'.

For example, the first and third columns in the table below
will be dynamically sized. The first column will take as
much space as required and the last column will expand so
that the table takes the full width of the text area.

!block example
!block  table; format=",30,,10"
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock
!endblock

The output is:

!block  table; format=",30,,10"
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock

However, in the example below, each column will only take
as much space is required, making the table narrower
than it would be otherwise.

!block example
!block  table; narrow
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock
!endblock

The output is:

!block  table; narrow
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock

If an = character is used in place of a - character for a column
width, then those columns will be equalised in size.
For example, the second and forth columns in the table
below will be made equal in size.

!block example
!block  table; format="20,5=30,10,="
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock
!endblock

The output is:

!block  table; format="20,5=30,10,="
Name    Column2             Column3     Column4
A       B                   C           D
X       Hello dear world    Y           Z
!endblock

Note: As previously, the {{format}} parameter has no impact on HTML
generation, i.e. all columns in HTML remain dynamically sized.
Dynamic sizing is also ignored for {{txt}} and {{pod}} targets.


H3: Heading/footing rows for tables

The {{FILT:table}} filter now supports the following attributes:

* {{headings}} - the number of heading rows at the top of the table
* {{footings}} - the number of footing rows at the end of the table.

If the {{headings}} attribute is not defined, then as previously done,
the column headings are generated using the column names given on
the {{parsing}} line. For example, the column headings in the table
below will be {{Name}} and {{Age}}:

!block example
!block table
Name    Age
Bill    42
!endblock
!endblock

Alternatively, if the {{headings}} attribute is defined,
then that number of {{data}} rows are used as the column headings,
i.e. the parsing line is not used to build the column headings.
For example, the column headings in the table below will be
{{"Title"}} and {{Age}} (remembering that a filter attribute is
implicitly given the value 1 is no value is supplied).

!block example
!block table; headings
A       B
"Title" Age
Bill    42
Sally   23
!endblock
!endblock

Likewise, the column headings below will be {{Preferred Title}} and
{{Likely Age}} with each heading taking 2 rows.

!block example
!block table; headings=2
A           B
Preferred   Likely
Title       Age
Bill        42
Sally       23
!endblock
!endblock

Collectively, these new attributes improve things in several ways:

* heading rows can now include non-alphanumeric characters
* macros (e.g. change bars) can be applied to heading rows
* multi-line heading and footing rows are now supported.


H3: Table positioning

The horizontal alignment and vertical placement of a table can be
controlled by setting the {{align}} and {{placement}} parameters
of the {{FILT:table}} filter respectively.
The permitted {{align}} values are:

!block table
Value       Meaning
Left        left-align the table
Center      center the table
Right       right-align the table
Inner       align the table with the inner margin
Outer       align the table with the outer margin
!endblock

Note: The {{wide}} parameter changes the left indent of a table
to include the sidehead of a page. Therefore, the {{wide}}
parameter will impact the horizontal positioning of any
table which is not right-aligned.

The permitted {{placement}} values are:

!block table
Value       Meaning
Float       next column if necessary
Pagetop     top of the next page
Columntop   top of the next column
Lefttop     top of the next left-hand page
Righttop    top of the next right-hand page
!endblock


H3: Table filtering and sorting

Tables can now be filtered and sorted by using the new {{where}}
and {{sort}} attributes of the {{FILT:table}} filter.
These attributes are also supported by the class filters (e.g.
terms, references).
In either case, filtering is done before sorting.

The {{where}} attribute takes an expression which is evaluated
for each record. Special symbols available are:

!block table
Symbol      Meaning
$_          the current record
$o{"xyz"}   the value of column xyz
!endblock

{{sort}} takes a comma-separated list of column names to sort on.
If no columns are specified, the data is sorted using
all columns in the order in which they appear. All sorting
is done alphabetically - numeric sorting is not supported.


H3: Landscape tables

Landscape tables are now supported via the {{landscape}} parameter of
the {{FILT:table}} filter. The value is the height allocated to
the area in which the table is placed. If a unit is not specified,
the value is assumed to be a percentage of the text column height.
For convenience, a value of 1 implies a full page table.
Some examples are given below.

!block table
Value               Meaning
landscape="50pt"    height allocated to table is 50 points
landscape="50%"     half page table
landscape=50        half page table (% is the default units)
landscape=1         full page table (1 implies 100%)
landscape           full page table (syntactic shorthand for above)
!endblock

Note: This feature is currently {{B:use at your own risk}}.
In particular, long tables and table titles confuse it badly.
Furthermore, the {{align}} and {{placement}} parameters are
effectively ignored for landscape tables.


H3: Column alignment

The {{colaligns}} parameter of the {{FILT:table}} filter can now be used
to control the alignment of text within columns of a table.
For example:

!block example
!block  table; colaligns="LCCR"
Name    Column2             Column3     Column4
A       B                   C           1.0
X       Hello dear world    Y           10.2
!endblock
!endblock

The output is:

!block  table; colaligns="LCCR"
Name    Column2             Column3     Column4
A       B                   C           1.0
X       Hello dear world    Y           10.2
!endblock

The value of {{colaligns}} is usually a sequence of the letters
{{L}}, {{C}} and {{R}} (which mean what one would expect).
If you prefer, a comma-separated list of the values {{Left}}, {{Center}}
and {{Right}} can be specified. For example:

!block example
!block  table; colaligns="Left,Center,Center,Right"
Name    Column2             Column3     Column4
A       B                   C           1.0
X       Hello dear world    Y           10.2
!endblock
!endblock


H3: Cell attributes

Cells within a table can now be given attributes by preceding the
cell value with a semicolon-separated list of name-value pairs
enclosed in square brackets. For example:

!block example
!block  table; colaligns="LCCR"
Name    Column2             Column3     Column4
A       [align=Left]B       C           [bgcolor=Green]1.0
X       Hello dear world    Y           [bgcolor=Red]10.2
!endblock
!endblock

The output is:

!block  table; colaligns="LCCR"
Name    Column2             Column3     Column4
A       [align=Left]B       C           [bgcolor=Green]1.0
X       Hello dear world    Y           [bgcolor=Red]10.2
!endblock

The cell attributes supported are given below.

!block table; groups
Name        Value
General:
align       horizontal alignment (Left, Center, Right)
valign      vertical alignment (Top, Middle, Bottom, Baseline)
cols        the number of columns this cell spans (default is 1)
rows        the number of rows this cell spans (default is 1)
bgcolor     background colour of cell (see below)
PS only:
fill        background colour fill percentage
truling     ruling setting for top of cell
bruling     ruling setting for bottom of cell
lruling     ruling setting for left of cell
rruling     ruling setting for right of cell
angle       angle of text (0, 90, 180, 270)
HTML only:
nowrap      disable word wrap for this cell
Special:
sdf         treat the cell text as SDF (rather than as phrase text)
tag         phrase tag to apply to cell text
paratag     paragraph style to apply to cell text
!endblock

For PS (i.e. MIF) generation, the supported colour values are
{{Black}}, {{White}}, {{Red}}, {{Green}},
{{Blue}}, {{Yellow}}, {{Cyan}} and {{Magenta}}.
If a different colour is specified, it is ignored.
The supported fill values are 100, 90, 70, 50, 30, 10 and 3.
If a fill value is not specified, 100% fill is used.

For HTML generation, any of the HTML colours names
(including those supported for PS generation) or the "#rrggbb" form
can be used.

The permitted ruling values are {{Vthin}}, {{Thin}}, {{Medium}},
{{Thick}} and {{Double}}.

The {{sdf}}, {{tag}} and {{paratag}} attributes control the way in which the
cell text is converted to SDF:

^ If {{sdf}} is set, the cell text is already SDF.
+ Otherwise if {{tag}} is set, the SDF paragraph is paratag:E<2{>tag:textE<2}>.
+ Otherwise, the paragraph is paratag:text.

{{tag}} is usually set via the {{tags}} or {{groups}} parameters
of the {{FILT:table}} filter.

Note: {{paratag}} is not yet implemented.


H3: Spreadsheet calculations

{{The spreadsheet expression evaluator and the documentation below
was written by Tim Hudson ({{EMAIL:tjh@cryptsoft.com}})}}.

Spreadsheet style calculations have been introduced into SDF using the
standard {{E<2[> E<2]>}} syntax with a prefix of {{+}} (or {{=}}) indicating
that the expression is to be evaluated by the calculation routines.

This extension has been loosely modelled on [[Microsoft]] {{Excel}}[[r]]
in terms of the initial functions supported and the syntax used.

Note: Calculation support for a table can be disabled by adding in 
an attribute of {{nocalcs}} (otherwise the pointers required to table
data that are needed when doing spreadsheet calculations occur for each
table cell).

Each {{cell}} in a table has an {{cellid}} which is made up of a
single uppercase letter indicating the column index and a number
indicating the row index (counting from 1 and excluding the
heading rows). The upper left {{cell}} is hence {{A1}}.

An example grid indicating {{cellid}}s:

!block table; narrow
Title1:Title2:Title3:Title4:Title5
A1:B1:C1:D1:E1
A2:B2:C2:D2:E2
A3:B3:C3:D3:E3
...:...:...:...:...
A100:B100:C100:D100:E100
!endblock

A range of {{cellid}}s is specified using the syntax {{:cellid1:cellid2}}.
For example: {{:A1:C1}} is exactly the same as {{A1,B1,C1}}

An expression consists of a combination of standard Perl operators
and spreadsheet functions and {{cellid}}s or {{cellid}} ranges.

Standard Perl operators include:

* + - * /

Spreadsheet functions use the syntax {{FUNCTION(ARG1,ARG2,...ARGN)}}.

The following functions are supported:

* {{AVERAGE}} - the average - SUM(ARGS)/COUNT(ARGS)
* {{SUM}} - the sum of the args - same as ARG1+ARG2+...+ARGN
* {{MIN}} - the minumum argument value 
* {{MAX}} - the maximum argument value
* {{COUNT}} - the number of arguments
* {{PRODUCT}} - the product of the args - same as ARG1*ARGN*...*ARGN
* {{ROWSUM}} - the {{SUM}} of all the cells in the row to the left of 
               the current cell
* {{ROWPROD}} - the {{PRODUCT}} of all the cells in the row to the 
                left of the current cell
* {{COLSUM}} - the {{SUM}} of all the cells in the column above the 
               current cell
* {{COLPROD}} - the {{PRODUCT}} of all the cells in the column above the 
                current cell

A simple example:

!block example
!block table; style="grid"
Count         Price        Total
10            5            [\[=A1*B1]\]
15            5.23         [\[=ROWPROD]\]
[\[=COLSUM]]   [\[=B1+B2]\]   [\[=COLSUM]\]
!endblock
!endblock

Which generates the result below. (Ok, summing two prices is
meaningless, but it illustrates the syntax.)

!block table; style="grid"
Count         Price        Total
10            5            [[=A1*B1]]
15            5.23         [[=ROWPROD]]
[[=COLSUM]]   [[=B1+B2]]   [[=COLSUM]]
!endblock

NB: 
values are available until the next table is processed so
you can refer to data inside {{normal}} paragraphs after 
the table like this [\[=A1]\] which evaluates to [[=A1]]
NE:

A spreadsheet expression will recursively evaluate any expressions
contained in {{cells}} that are used in an expression. In the example
above, the expression in {{cell}} {{C3}} depends on the results of the
expression in {{cell}} {{C1}} and {{C2}}.


H3: Arbitrary page sizes

Generally speaking, SDF can now support arbitrary page sizes.
The catch is that the page size must now be specified up front
via the OPT_PAGE_SIZE variable on the {{MAC:init}} line or via
{{CMD:sdf}}'s -S option. (Previously, the (no longer
supported) DOC_PAGE_SIZE variable could be
specified anywhere in the document.)

The supported values of OPT_PAGE_SIZE are given below.
The default page size is {{global}}.

!block table
Name    Width   Height  Comment
global  21.0cm  11.0in  will fit on either A4 or letter
A3      29.7cm  42.0cm 
A4      21.0cm  29.7cm
A5      14.8cm  21.0cm
B4      25.7cm  36.4cm
B5      17.6cm  25.0cm
letter  8.5in   11.0in
legal   8.5in   14.0in
tabloid 11.0in  17.0in
!endblock

Note: {{global}} is 0.23" narrower than {{letter}} and 1.76cm shorter
than {{A4}}.

New page sizes can be defined in {{FILE:sdf.ini}}.
A rotated version is also available for each page size.
Rotated sizes are named with an appended R.
For example, the rotated A4 size is called A4R.


H3: Headers and footers

SDF now provides 3 ways of controlling headers and footers:

* The OPT_HEADINGS variable (high level control)
* PAGE_{{page}}_{{HF}}_{{ICO}}{{n}} variables (medium level control)
* PAGE_{{page}}_{{HF}} macros (low level control)

:where:

* {{page}} is FIRST, RIGHT or LEFT
* {{HF}} is HEADER or FOOTER
* {{ICO}} is INNER, CENTER or OUTER
* {{n}} is the line number within the header or footer (usually 1 or 2).

The meaning of each page type is explained below.

!block table
Page    Usage
FIRST   the first page in the document
RIGHT   the page used for single-sided documents and the right hand side of double-sided documents
LEFT    the left hand side of double-sided documents; ignored for single-sided documents
!endblock

Supported OPT_HEADINGS values and their meanings are given below:

!block table
Value       Meaning
0           no header, no footer
1           single line header, single line footer
2           two line header and two line footer
3           two line header and three line footer
4           two line header and four line footer
!endblock


H3: Header/footer special tags

The following special tags are supported within headers and footers:

!block table
Tag             Meaning
PAGENUM         current page number
PAGECOUNT       highest page number
PARATEXT        paragraph text (e.g. Hardware requirements)
PARANUM         paragraph number (e.g. Appendix A)
PARANUMONLY     paragraph number only (e.g. A)
PARASHORT       value of {{short}} attribute of paragraph
PARALAST        text of last paragraph on page with the nominated style
!endblock

The {{PARA*}} tags require a comma separated list of paragraph styles
to be nominated as the text of the phrase, e.g. E<2{>PARATEXT:H1,A1,P1E<2}>.

The {{PARASHORT}} tag is useful for placing an alternative heading
in a header, say. For example, you might set up your header to include
E<2{>PARASHORT:H1E<2}> and have the following text in your document:

E:  H1[short='Getting started'] Getting started with SDF

The {{PARALAST}} tag is useful for producing dictionary-like headers.


H3: Header/footer borders

High level control over header/footer borders is provided by
the OPT_BORDERS variable. The supported values and their meanings
are given below:

!block table
Value       Meaning
0           no header/footer borders
1           line below header, line above footer
2           lines above and below header, line above footer
!endblock

Finer control is available by setting the following variables:

!block table
Name                         Value
PAGE_{{page}}_HEADER_BORDER  border specification string
PAGE_{{page}}_FOOTER_BORDER  border specification string
!endblock

where {{page}} is either FIRST, RIGHT or LEFT.

A {{border specification}} string is a comma-separated list
of attributes which collectively describe the border.
The format of each attribute is name[=value].
The supported attributes are:

* {{top}} - a line above the area
* {{bottom}} - a line below the area
* {{box}} - a box around the area
* {{radius}} - for a box, the radius of the corner.

For {{top}}, {{bottom}} and {{box}}, the value of the
attribute is the line width in points.


H3: Page backgrounds

In order to support fancy background images, SDF supports
the following variables:

!block table
Name                         Value
PAGE_{{page}}_BACKGROUND     the logical image name
!endblock

where {{page}} is either FIRST, RIGHT or LEFT.

When [[FrameMaker]] is being used to generate [[PostScript]],
the image name is mapped to a master page called {{backgrnd}} within a file
called {{backgrnd}}.mif.

Note: At the moment, objects from the master page
(excluding TextRects) are directly transferred to the
generated MIF file. This means that objects in the
lower right hand corner of an A4 master page will not
will be positioned nicely if the paper size is changed
to A5, say.


H3: Page layout variables

Page margins can now be controlled via the following variables:

!block table
Name                Value
OPT_MARGIN_TOP      size of the margin above the header, if any
OPT_MARGIN_BOTTOM   size of the margin below the footer, if any
OPT_MARGIN_INNER    size of the inner margin
OPT_MARGIN_OUTER    size of the outer margin
!endblock

The positioning of headers and footers can now be controlled via
the following variables:

!block table
Name                         Value
PAGE_{{page}}_HEADER_HEIGHT  height of the area allocated to the header
PAGE_{{page}}_HEADER_GAP     size of the gap between the header area and the text area
PAGE_{{page}}_FOOTER_HEIGHT  height of the area allocated to the footer
PAGE_{{page}}_FOOTER_GAP     size of the gap between the text area and the footer area
!endblock

where {{page}} is either FIRST, RIGHT or LEFT.

After the margins and header/footer are allocated, the remaining text
area contains 1 or more text columns and an optional side head.
The layout of these is controlled by the following variables:

!block table
Name                Value
OPT_COLUMNS         numbers of text columns
OPT_COLUMN_GAP      space between columns
OPT_SIDEHEAD_WIDTH  size allocated to the sidehead
OPT_SIDEHEAD_GAP    space between the side-head and first text column
!endblock

The following read-only variables provide information on the
page layout:

!block table
Name                    Value
DOC_PAGE_WIDTH          width of page
DOC_PAGE_HEIGHT         height of page
DOC_FULL_WIDTH          width of text area including the side-head
DOC_TEXT_WIDTH          width of text area available for text columns
DOC_TEXT_HEIGHT         height of text area
DOC_COLUMN_WIDTH        width of a text column
!endblock

All the information variables are in units of points.
The text area is the area allocated to text, excluding the header
and footer (if any) on the RIGHT page.


H3: Page control within a book

When a book is being generated, each component of the book
may have its own FIRST, RIGHT and LEFT pages, i.e. all of
the macros and variables above support an extended set of
{{page}} values {{component}}_{{FRL}} where:

* {{component}} is the name of the component
* {{FRL}} is FIRST, RIGHT or LEFT.

The component names supported are given below.

!block table
Name                Meaning
FRONT               the cover component
PRETOC              components before the contents
TOC                 the table of contents
LOF                 the list of figures
LOT                 the list of tables
PRECHAPTER          components before the chapters
CHAPTER             a normal chapter
APPENDIX            an appendix
PREIX               components before the index
IX                  the index
!endblock

If a component does not have a component-specific macro/variable
defined, then the generic macro/variable is used.


H3: FrameMaker templates are no longer required

Previously, SDF produced MIF documents by merging
generated MIF paragraphs into FrameMaker templates.
This approach was easy to implement but maintaining
the FrameMaker templates was difficult as
every look required several templates for {{each}} page size!

FrameMaker templates can still be used but are no longer
needed, nor recommended. Instead, the definitions of
paragraph styles, phrase styles, table styles and graphic
(border) frames is now done via {{SDF templates}}.
SDF templates have the following advantages:

^ Templates can be parameterised so that
  a single template can support any number of page sizes.

+ Each look only requires a single template, rather than
  a template for each component of a FrameMaker book.

+ Templates can inherit definitions from other templates,
  making it much easier to create and maintain templates.

+ Each definition supports inheritance, so a new paragraph
  style, say, can be defined in terms of the differences
  between it and a parent style.

The new {{sdtgen}} command can be used to build an SDF
template from a FrameMaker one. Typically, {{sdtgen}} is
used to create an initial template which is then simplified via
definition inheritance and template inheritance.


H3: Event processing enhancements

The following new symbols are now available within event processing
for paragraphs:

!block table
Symbol      Meaning
$level      the current heading level ({{before}} this paragraph)
$prev_style the style of the previous paragraph
$prev_text  the text of the previous paragraph
%prev_attr  the attributes of the previous paragraph
!endblock

These symbols make it much easier to do some really nice things.
For example, the following rule can be used 
to put level 2 headings on a new page unless
the heading is the first one within a chapter:

!block example
!on paragraph '[HAP]2';; if ($level != 1) {$attr{'top'} = 1}
!endblock


H2: Fixes

Tim Hudson has contributed a number of fixes to this release including:

* this version should now work with Perl 5 again - the previous
  version triggered a Perl 5 syntax error

* the {{IMPORT}} pragma now supports filename extension adding ala
  the {{MAC:import}} macro

* centred figures now work as expected in HTML

* numerous Windows help generation fixes/enhancements.

Other fixes include:

* the renaming of xx.out.ps to xx.ps is now done by {{CMD:sdfbatch}},
  so failures (due to lack of disk space, say) are now handled much
  better than they previously were

* topics mode now generates an error if the heading of a topic
  is duplicated within a file (see {{SECT:Miscellaneous things}} above)

* headings containing a ? character should no longer cause problems

* some bugs in {{CMD:sdfget}}'s extraction of documentation from C code
  have been fixed (thanks to Keith Ponting).

H2: Incompatibilities

As the default page size is now {{global}} rather than {{A4}},
page breaks may occur slightly earlier than they previously did.
The advantage of changing to {{global}} is that documents
should now print successfully on US letter paper.

Memos, faxes, minutes and newsletters no longer have the company
address in the top right hand corner. (I'll fix this soon, but it
is not a high priority at the moment.)

As {{txt}} and {{pod}} outputs use a different algorithm for
deciding column widths when a table does not have a format parameter,
some table cells may no longer fit when these output formats are used.

The table attribute previously called {{headings}} has been
renamed to {{parseline}} to better reflect its purpose and to
make way for the new meaning.

The DOC_TOCTEXT variable has been renamed to DOC_TOC_TITLE.
The DOC_TOCGRAPHIC variable has been renamed to DOC_TOC_GRAPHIC.

The {{newsletter}} style has been renamed to {{newslttr}}.

{{overhead}} is now a look, rather than a style. The overhead look
is untested and rarely used, so use it at your own risk.

The aliases {{sdf2htmls}} and {{sdf2txts}} have been renamed to
{{sdf2fmhtml}} and {{sdf2fmtxt}} respectively.

{{FILE:/usr/local/bin/perl5}} is now the default perl interpreter used.