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The refined formatting object tree describes one or more intended presentations of the information within this tree. Formatting is the process which converts the description into a presentation. See [3 Introduction to Formatting]. The presentation is represented, abstractly, by an area tree, as defined in the area model. See [4 Area Model]. Each possible presentation is represented by one or more area trees in which the information in the refined formatting object tree is positioned on a two and one-half dimensional surface.
There are three kinds of formatting objects: (1) those that generate areas, (2) those that return areas, but do not generate them, and (3) those that are used in the generation of areas. The first and second kinds are typically called flow objects. The third kind is either a layout object or an auxiliary object. The kind of formatting object is indicated by the terminology used with the object. Formatting objects of the first kind are said to "generate one or more areas". Formatting objects of the second kind are said to "return one or more areas". Formatting objects of the first kind may both generate and return areas. Formatting objects of the third kind are "used in the generation of areas"; that is, they act like parameters to the generation process.
This categorization leads to defining two traits which characterize the relationship between an area and the formatting objects which generate and return that area. These traits are generated-by and returned-by.
The value of the generated-by trait is a single formatting object. A formatting object F is defined to generate an area A if the semantics of F specify the generation of one or more areas and A is one of the areas thus generated, or is a substituted form of one of the areas thus generated, as specified in section [4.7.2 Line-building].
In the case of substituted glyph-areas, the generating formatting object is deemed to be the formatting object which generated the glyph-area which comes first in the sequence of substituted glyph-areas. In the case of an inserted glyph-area (e.g., an automatically-generated hyphen) the generating formatting object is deemed to be the generating formatting object of the last glyph-area preceding the inserted glyph-area in the pre-order traversal of the area tree.
The value of the returned-by trait is a set of pairs, where each pair consists of a formatting object and a positive integer. The integer represents the position of the area in the ordering of all areas returned by the formatting object.
A formatting object F is defined to return the sequence of areas A, B, C, ... if the pair (F,1) is a member of the returned-by trait of A, the pair (F,2) is a member of the returned-by trait of B, the pair (F,3) is a member of the returned-by trait of C, ...
If an area is a member of the sequence of areas returned by a formatting object, then either it was generated by the formatting object or it was a member of the sequence of areas returned by a child of that formatting object. Not all areas returned by a child of a formatting object need be returned by that formatting object. A formatting object may generate an area that has, as some of its children areas, areas returned by the children of that formatting object. These children (in the area tree) of the generated area are not returned by the formatting object to which they were returned.
A set of nodes in a tree is a lineage if:
there is a node N in the set such that all the nodes in the set are ancestors of N, and
for every node N in the set, if the set contains an ancestor of N, it also contains the parent of N.
The set of formatting objects that an area is returned by is a lineage.
Areas returned by a formatting object may be either normal or out-of-line. Normal areas represent areas in the "normal flow of text"; that is, they become area children of the areas generated by the formatting object to which they are returned. Normal areas have a returned-by lineage of size one. There is only one kind of normal area.
Out-of-line areas are areas used outside the normal flow of text either because they are absolutely positioned or they are part of a float or footnote. Out-of-line areas may have a returned-by lineage of size greater than one.
The area-class trait indicates which class, normal or out-of-line, an area belongs to. For out-of-line areas, it also indicates the subclass of out-of-line area. The values for this trait are: "xsl-normal", "xsl-absolute", "xsl-footnote", "xsl-side-float", or "xsl-before-float". An area is normal if and only if the value of the area-class trait is "xsl-normal"; otherwise, the area is an out-of-line area. (See section [4.2.5 Stacking Constraints].)
The areas returned-by a given formatting object are ordered as noted above. This ordering defines an ordering on the sub-sequence of areas that are of a given area-class, such as the sub-sequence of normal areas. An area A precedes an area B in the sub-sequence if and only if area A precedes area B in the areas returned-by the formatting objects.
A reference-area chain is defined as a sequence of reference-areas that is either generated by the same formatting object that is not a page-sequence formatting object, or that consists of the region reference-areas or normal-flow-reference-areas (see [6.4.13 fo:region-body]) generated using region formatting objects assigned to the same flow (see [6.4.1.4 Flows and Flow Mapping]. The reference-areas in the sequence are said to be "contained" by the reference-area chain, and they have the same ordering relative to each other in the sequence as they have in the area tree, using pre-order traversal order of the area tree.
The content of a formatting object is described using XML content-model syntax. In some cases additional constraints, not expressible in XML content models, are given in prose.
The parameter entity, "%block;" in the content models below, contains the following formatting objects:
block
block-container
table-and-caption
table
list-block
The parameter entity, "%inline;" in the content models below, contains the following formatting objects:
bidi-override
character
external-graphic
instream-foreign-object
inline
inline-container
leader
page-number
page-number-citation
basic-link
multi-toggle
The following formatting objects are "neutral" containers and may be used, provided that the additional constraints listed under each formatting object are satisfied, anywhere where #PCDATA, %block;, or %inline; are allowed:
multi-switch
multi-properties
wrapper
retrieve-marker
The following "out-of-line" formatting objects may be used anywhere where #PCDATA, %block;, or %inline; are allowed (except as a descendant of any "out-of-line" formatting object):
float
The following "out-of-line" formatting objects may be used anywhere where #PCDATA or %inline; are allowed (except as a descendant of any "out-of-line" formatting object):
footnote
The fo:basic-link is used for representing the start resource of a simple link.
The fo:bidi-override inline formatting object is used where it is necessary to override the default Unicode-bidirectionality algorithm direction for different (or nested) inline scripts in mixed-language documents.
The fo:block formatting object is commonly used for formatting paragraphs, titles, headlines, figure and table captions, etc.
The fo:block-container flow object is used to generate a block-level reference-area.
The fo:character flow object represents a character that is mapped to a glyph for presentation.
Used to declare a color profile for a stylesheet.
The fo:conditional-page-master-reference is used to identify a page-master that is to be used when the conditions on its use are satisfied.
Used to group global declarations for a stylesheet.
The fo:external-graphic flow object is used for a graphic where the graphics data resides outside of the XML result tree in the fo namespace.
The fo:float serves two purposes. It can be used so that during the normal placement of content, some related content is formatted into a separate area at beginning of the page (or of some following page) where it is available to be read without immediately intruding on the reader. Alternatively, it can be used when an area is intended to float to one side, with normal content flowing alongside.
The content of the fo:flow formatting object is a sequence of flow objects that provides the flowing text content that is distributed into pages.
The fo:footnote is used to produce a footnote citation and the corresponding footnote.
The fo:footnote-body is used to generate the content of the footnote.
The fo:initial-property-set specifies formatting properties for the first line of an fo:block.
The fo:inline formatting object is commonly used for formatting a portion of text with a background or enclosing it in a border.
The fo:inline-container flow object is used to generate an inline reference-area.
The fo:instream-foreign-object flow object is used for an inline graphic or other "generic" object where the object data resides as descendants of the fo:instream-foreign-object.
The fo:layout-master-set is a wrapper around all masters used in the document.
The fo:leader formatting object is used to generate leaders consisting either of a rule or of a row of a repeating character or cyclically repeating pattern of characters that may be used for connecting two text formatting objects.
The fo:list-block flow object is used to format a list.
The fo:list-item formatting object contains the label and the body of an item in a list.
The fo:list-item-body formatting object contains the content of the body of a list-item.
The fo:list-item-label formatting object contains the content of the label of a list-item; typically used to either enumerate, identify, or adorn the list-item's body.
The fo:marker is used in conjunction with fo:retrieve-marker to produce running headers or footers.
The fo:multi-case is used to contain (within an fo:multi-switch) each alternative sub-tree of formatting objects among which the parent fo:multi-switch will choose one to show and will hide the rest.
The fo:multi-properties is used to switch between two or more property sets that are associated with a given portion of content.
The fo:multi-property-set is used to specify an alternative set of formatting properties that, dependent on a User Agent state, are applied to the content.
The fo:multi-switch wraps the specification of alternative sub-trees of formatting objects (each sub-tree being within an fo:multi-case), and controls the switching (activated via fo:multi-toggle) from one alternative to another.
The fo:multi-toggle is used within an fo:multi-case to switch to another fo:multi-case.
The fo:page-number formatting object is used to represent the current page-number.
The fo:page-number-citation is used to reference the page-number for the page containing the first normal area returned by the cited formatting object.
The fo:page-sequence formatting object is used to specify how to create a (sub-)sequence of pages within a document; for example, a chapter of a report. The content of these pages comes from flow children of the fo:page-sequence.
The fo:page-sequence-master specifies sequences of page-masters that are used when generating a sequence of pages.
This region defines a viewport that is located on the "after" side of fo:region-body region.
This region defines a viewport that is located on the "before" side of fo:region-body region.
This region specifies a viewport/reference pair that is located in the "center" of the fo:simple-page-master.
This region defines a viewport that is located on the "end" side of fo:region-body region.
This region defines a viewport that is located on the "start" side of fo:region-body region.
An fo:repeatable-page-master-alternatives specifies a sub-sequence consisting of repeated instances of a set of alternative page-masters. The number of repetitions may be bounded or potentially unbounded.
An fo:repeatable-page-master-reference specifies a sub-sequence consisting of repeated instances of a single page-master. The number of repetitions may be bounded or potentially unbounded.
The fo:retrieve-marker is used in conjunction with fo:marker to produce running headers or footers.
The fo:root node is the top node of an XSL result tree. This tree is composed of formatting objects.
The fo:simple-page-master is used in the generation of pages and specifies the geometry of the page. The page may be subdivided into up to five regions.
An fo:single-page-master-reference specifies a sub-sequence consisting of a single instance of a single page-master.
The fo:static-content formatting object holds a sequence or a tree of formatting objects that is to be presented in a single region or repeated in like-named regions on one or more pages in the page-sequence. Its common use is for repeating or running headers and footers.
The fo:table flow object is used for formatting the tabular material of a table.
The fo:table-and-caption flow object is used for formatting a table together with its caption.
The fo:table-body formatting object is used to contain the content of the table body.
The fo:table-caption formatting object is used to contain block-level formatting objects containing the caption for the table only when using the fo:table-and-caption.
The fo:table-cell formatting object is used to group content to be placed in a table cell.
The fo:table-column formatting object specifies characteristics applicable to table cells that have the same column and span.
The fo:table-footer formatting object is used to contain the content of the table footer.
The fo:table-header formatting object is used to contain the content of the table header.
The fo:table-row formatting object is used to group table-cells into rows.
The fo:title formatting object is used to associate a title with a given document. This title may be used by an interactive User Agent to identify the document. For example, the content of the fo:title can be formatted and displayed in a "title" window or in a "tool tip".
The fo:wrapper formatting object is used to specify inherited properties for a group of formatting objects. It has no additional formatting semantics.
The root node of the formatting object tree must be an fo:root formatting object. The children of the fo:root formatting object are a single fo:layout-master-set, an optional fo:declarations, and a sequence of one or more fo:page-sequences. The fo:layout-master-set defines the geometry and sequencing of the pages; the children of the fo:page-sequences, which are called flows (contained in fo:flow and fo:static-content), provide the content that is distributed into the pages. The fo:declarations object is a wrapper for formatting objects whose content is to be used as a resource to the formatting process. The process of generating the pages is done automatically by the XSL processor formatting the result tree.
The children of the fo:layout-master-set are the pagination and layout specifications. The names of these specifications end in "-master". There are two types of pagination and layout specifications: page-masters and page-sequence-masters. Page-masters have the role of describing the intended subdivisions of a page and the geometry of these subdivisions. Page-sequence-masters have the role of describing the sequence of page-masters that will be used to generate pages during the formatting of an fo:page-sequence.
Each fo:page-sequence-master characterizes a set of possible sequences of page-masters. For any given fo:page-sequence, only one of the possible set of sequences will be used. The sequence that is used is any sequence that satisfies the constraints determined by the individual page-masters, the flows which generate pages from the page-masters, and the fo:page-sequence-master itself.
The fo:page-sequence-master is used to determine which page-masters are used and in which order. The children of the fo:page-sequence-master are a sequence of sub-sequence specifications. The page-masters in a sub-sequence may be specified by a reference to a single page-master or as a repetition of one or more page-masters. For example, a sequence might begin with several explicit page-masters and continue with a repetition of some other page-master (or masters).
The fo:single-page-master-reference is used to specify a sub-sequence consisting of a single page-master.
There are two ways to specify a sub-sequence that is a repetition. The fo:repeatable-page-master-reference specifies a repetition of a single page-master. The fo:repeatable-page-master-alternatives specifies the repetition of a set of page-masters. Which of the alternative page-masters is used at a given point in the sub-sequence is conditional and may depend on whether the page number is odd or even, is the first page, is the last page, or is blank. The "maximum-repeats" property on the repetition specification controls the number of repetitions. If this property is not specified, there is no limit on the number of repetitions.
A page-master is a master that is used to generate a page. A page is a viewport/reference pair in which the viewport-area is a child of the area tree root. A page-viewport-area is defined to be the viewport-area of a page, and a page-area is defined to be the unique child of a page-viewport-area.
The page-viewport-area is defined by the output medium; the page-area holds the page contents and has the effect of positioning the page contents on the output medium.
A single page-master may be used multiple times. Each time it is used it generates a single page; for example, a page-master that is referenced from an fo:repeatable-page-master-reference will be used by the fo:page-sequence to generate one page for each occurrence of the reference in the specified sub-sequence.
NOTE:When pages are used with a User Agent such as a Web browser, it is common that the each document has only one page. The viewport used to view the page determines the size of the page. When pages are placed on non-interactive media, such as sheets of paper, pages correspond to one or more of the surfaces of the paper. The size of the paper determines the size of the page.
In this specification, there is only one kind of page-master, the fo:simple-page-master. Future versions of this specification may add additional kinds of page-masters.
An fo:simple-page-master has, as children, specifications for one or more regions.
A region specification is used as a master, the region-master, in generating viewport/reference pair consisting of a region-viewport-area and a region-reference-area. The region-viewport-area is always a child of a page-area generated using the parent of the region-master.
NOTE:The regions on the page are analogous to "frames" in an HTML document. Typically, at least one of these regions is of indefinite length in one of its dimensions. For languages with a lr-tb (or rl-tb) writing-mode, this region is typically of indefinite length in the top-to-bottom direction. The viewport represents the visible part of the frame. The flow assigned to the region is viewed by scrolling the region reference-area through the viewport.
Each region is defined by a region formatting object. Each region formatting object has a name and a definite position. In addition, the region's height or width is fixed and the other dimension may be either fixed or indefinite. For example, a region that is the body of a Web page may have indefinite height.
The specification of the region determines the size and position of region-viewport-areas generated using the region formatting object. The positioning of the viewport is relative to its page-area parent.
For version 1.0 of this recommendation, a page-master will consist of up to five regions: "region-body" and four other regions, one on each side of the body. To allow the side regions to correspond to the current writing-mode, these regions are named "region-before" (which corresponds to "header" in the "lr-tb" writing-mode), "region-after" (which corresponds to "footer" in the "lr-tb" writing-mode), "region-start" (which corresponds to a "left-sidebar" in the "lr-tb" writing-mode) and "region-end" (which corresponds to a "right-sidebar" in the "lr-tb" writing-mode). It is expected that a future version of the recommendation will introduce a mechanism that allows a page-master to contain an arbitrary number of arbitrarily sized and positioned regions.
Some types of region have conditional sub-regions associated with them, and the associated region-reference-areas are divided up by having child areas corresponding to the sub-regions, including a "main-reference-area" for the region. For region-masters to which the column-count property applies, the main-reference-area is further subdivided by having child-areas designated as "span-reference-areas" whose number depends upon the number of spans (i.e. block-areas with span="all") occurring on the page. These in turn are subdivided by having child-areas designated as "normal-flow-reference-areas", whose number depends on the number of columns specified.
Pages are generated by the formatter's processing of fo:page-sequences. As noted above, each page is a viewport/reference pair in which the viewport-area is a child of the area tree root. Each page is generated using a page-master to define the region-viewport-areas and region-reference-areas that correspond to the regions specified by that page-master.
Each fo:page-sequence references either an fo:page-sequence-master or a page-master. If the reference is to a page-master, this is interpreted as if it were a reference to an fo:page-sequence-master that repeats the referenced page-master an unbounded number of times. An fo:page-sequence references a page-master if either the fo:page-sequence directly references the page-master via the "master-name" property or that property references an fo:page-sequence-master that references the page-master.
There are two kinds of flows: fo:static-content and fo:flow. An fo:static-content flow holds content, such as the text that goes into headers and footers, that is repeated on many of the pages. The fo:flow flow holds content that is distributed across a sequence of pages. The processing of the fo:flow flow is what determines how many pages are generated to hold the fo:page-sequence. The fo:page-sequence-master is used as the generator of the sequence of page-masters into which the flow children content is distributed.
The children of a flow are a sequence of block-level flow objects. Each flow has a name that is given by its "flow-name" property. No two flows may have the same name.
The assignment of flows to regions on a page-master is determined by a flow-map. The flow-map is an association between the flow children of the fo:page-sequence and regions defined within the page-masters referenced by that fo:page-sequence.
In version 1.0 of this recommendation, the flow-map is implicit. The "flow-name" property of a flow specifies to which region that flow is assigned. Each region has a "region-name" property. The implicit flow-map assigns a flow to the region that has the same name. In future versions of XSL, the flow-map is expected to become an explicit formatting object.
To avoid requiring users to generate region-names, the regions all have default values for the "region-name" property. The region-body, region-before, region-after, region-start, and region-end have the default names "xsl-region-body", "xsl-region-before", "xsl-region-after", "xsl-region-start", and "xsl-region-end", respectively.
In addition, an fo:static-content formatting object may have a "region-name" property value of "xsl-before-float-separator" or "xsl-footnote-separator". If a conditional sub-region of the region-body is used to generate a reference-area on a particular page, the fo:static-content whose name corresponds to the conditional sub-region shall be formatted into the reference-area associated with the sub-region, as specified in section [6.10.1.3 Conditional Sub-Regions].
The areas that are descendants of a page-area are constrained by the
page-master used to generate the page-area and the flows that are assigned to
the regions specified on the page-master. For fo:flow flows, the areas generated
by the descendants of the flow are distributed across the pages in the sequence
that were generated using page-masters having the region to which the flow is
assigned. For fo:static-content flows, the processing of the flow is repeated
for each page generated using a page-master having the region to which the flow
is assigned with two exceptions: for a fo:static-content with a flow-name
of xsl-before-float-separator, the processing is repeated only for
those page-reference-areas which have descendant areas with an area-class of
xsl-before-float, and for a fo:static-content with a
flow-name of xsl-footnote-separator, the processing is
repeated only for those page-reference-areas which have descendant areas with an
area-class of xsl-footnote.
The result tree structure is shown below.
Common Usage:
This is the top node of the formatting object tree. It holds an fo:layout-master-set formatting object (which holds all masters used in the document), an optional fo:declarations, and one or more fo:page-sequence objects. Each fo:page-sequence represents a sequence of pages that result from formatting the content children of the fo:page-sequence.
NOTE:A document can contain multiple fo:page-sequences. For example, each chapter of a document could be a separate fo:page-sequence; this would allow chapter-specific content, such as the chapter title, to be placed within a header or footer.
Areas:
Page-viewport-areas are returned by the fo:page-sequence children of the fo:root formatting object. The fo:root does not generate any areas.
Constraints:
The children of the root of the area tree consist solely of, and totally of, the page-viewport-areas returned by the fo:page-sequence children of the fo:root. The set of all areas returned by the fo:page-sequence children is properly ordered. (See Section [4.7.1 General Ordering Constraints].)
Contents:
(layout-master-set,declarations?,page-sequence+)
The following properties apply to this formatting object:
Common Usage:
The fo:declarations formatting object is used to group global declarations for a stylesheet.
Areas:
The fo:declarations formatting object does not generate or return any areas.
Constraints:
None.
Contents:
(color-profile)+
The fo:declarations flow object may have additional child elements in a non-XSL namespace. Their presence does not, however, change the semantics of the XSL namespace objects and properties. The permitted structure of these non-XSL namespace elements is defined for their namespace(s).
Common Usage:
The fo:color-profile formatting object is used to declare an ICC Color Profile for a stylesheet. The color-profile is referenced again via the name specified in the "color-profile-name" property.
The color-profile is identified by the URI specified in the "src" property value. This URI may identify an internally recognized color-profile or it may point to a ICC Color Profile encoding that should be loaded and interpreted.
When the color-profile is referenced (e.g., via the icc-color function[5.10.2 Color Functions]), the following rules are used:
If the color-profile is available, the color value identified from the color-profile should be used.
If the color-profile is not available, the sRGB fallback must be used.
Areas:
The fo:color-profile formatting object does not generate or return any areas.
Constraints:
None.
Contents:
EMPTY
The following properties apply to this formatting object:
Common Usage:
The fo:page-sequence formatting object is used to specify how to create a (sub-)sequence of pages within a document; for example, a chapter of a report. The content of these pages comes from flow children of the fo:page-sequence. The layout of these pages comes from the fo:page-sequence-master or page-master referenced by the master-name trait on the fo:page-sequence. The sequence of areas returned by each of the flow-object children of the fo:page-sequence are made descendants of the generated pages as described below.
Areas:
The fo:page-sequence formatting object generates a sequence of viewport/reference pairs, and returns the page-viewport-areas. For each page-reference-area, and each region specified in the page-master used to generate that page-reference-area, the fo:page-sequence object also generates the viewport/reference pair for the occurrence of that region in that page-reference-area, and may generate a before-float-reference-area, footnote-reference-area, and main-reference-area, and one or more normal-sequence-reference-areas. The generation of these further areas is described in the descriptions of the fo:simple-page-master and region-masters.
All areas generated by an fo:page-sequence have area-class "xsl-absolute".
Constraints:
Each page-viewport-area/page-reference-area pair is generated using a page-master that satisfies the constraints of the page-sequence-master identified by the master-name trait of the fo:page-sequence or a page-master that was directly identified by the master-name trait. The region-viewport-area children of such a page-reference-area must correspond to the regions that are children of that page-master.
The areas generated by the fo:page-sequence have as their descendants the areas returned by the flows that are children of the fo:page-sequence.
The areas returned to the fo:page-sequence by a flow must satisfy four types of constraints:
Completeness. All areas returned by formatting object descendants of the flow children of the fo:page-sequence become descendants of areas generated by the fo:page-sequence, with the exception of glyph-areas subject to deletion or substitution as in Sections [4.7.2 Line-building] and [4.7.3 Inline-building].
Flow-map association. All areas returned by flow children of the
fo:page-sequence become descendants of region-reference-areas generated from
column-areas associated to the flow by the flow-map in effect, except for
areas returned from a fo:static-content with a flow-name of
xsl-before-float-separator or
xsl-footnote-separator.
Areas returned from an fo:static-content with a flow-name of
xsl-before-float-separator become children of the
before-float-reference-area of an area associated to an fo:region-body,
following all sibling areas of area-class xsl-before-float. Areas
returned from an fo:static-content with a flow-name of
xsl-footnote-separator become children of the
footnote-reference-area of an area associated to an fo:region-body, preceding
all sibling areas of area-class xsl-footnote.
Area-class association. Areas returned by flow children of an
fo:page-sequence are distributed as follows: all areas of area-class
xsl-footnote must be descendants of a footnote-reference-area;
areas of area-class xsl-before-float must be descendants of a
before-float-reference-area; all other areas (including normal areas) must be
descendants of a main-reference-area for a region.
Stacking. The stackable areas of a given class returned by children of each flow are properly stacked within the appropriate reference-area, as described above.
The default ordering constraint of section [4.7.1 General Ordering Constraints] does not apply to the fo:page-sequence. The default ordering constraints apply to the child fo:flow objects; special ordering constraints apply to the child fo:static-content objects.
Contents:
(title?,static-content*,flow)
The following properties apply to this formatting object:
Common Usage:
The fo:layout-master-set is a wrapper around all masters used in the document. This includes page-sequence-masters, page-masters, and region-masters.
Areas:
The fo:layout-master-set formatting object generates no area directly. The masters that are the children of the fo:layout-master-set are used by the fo:page-sequence to generate pages.
Constraints:
The value of the master-name trait on each child of the fo:layout-master-set must be unique within the set.
Contents:
(simple-page-master|page-sequence-master)+
Common Usage:
The fo:page-sequence-master is used to specify the constraints on and the order in which a given set of page-masters will be used in generating a sequence of pages. Pages are automatically generated when the fo:page-sequence-master is used in formatting an fo:page-sequence.
NOTE:There are several ways of specifying a potential sequence of pages. One can specify a sequence of references to particular page-masters. This yields a bounded sequence of potential pages. Alternatively, one can specify a repeating sub-sequence of one or more page-masters. This sub-sequence can be bounded or unbounded. Finally one can intermix the two kinds of sub-sequence-specifiers.
Areas:
The fo:page-sequence-master formatting object generates no area directly. It is used by the fo:page-sequence formatting object to generate pages.
Constraints:
The children of the fo:page-sequence-master are a sequence of sub-sequence-specifiers. A page-sequence satisfies the constraint determined by an fo:page-sequence-master if (a) it can be partitioned into sub-sequences of pages that map one-to-one, in order, to the sub-sequence of sub-sequence-specifiers that are the children of the fo:page-sequence-master and, (b) for each sub-sequence of pages, that sub-sequence satisfies the constraints of the corresponding sub-sequence-specifier. Note that the mapping of sub-sequences of the sequence of pages to sub-sequence-specifiers need not be onto; that is, the sequence of sub-sequences of pages can be shorter than the sequence of sub-sequence-specifiers.
It is an error if the entire sequence of sub-sequence-specifiers children is exhausted while some areas returned by an fo:flow are not placed. Implementations may recover, if possible, by re-using the sub-sequence-specifier that was last used to generate a page.
Contents:
(single-page-master-reference|repeatable-page-master-reference|repeatable-page-master-alternatives)+
The following properties apply to this formatting object:
Common Usage:
An fo:single-page-master-reference is the simplest sub-sequence-specifier. It specifies a sub-sequence consisting of a single instance of a single page-master. It is used to specify the use of a particular page-master at a given point in the sequence of pages that would be generated using the fo:page-sequence-master that is the parent of the fo:single-page-master-reference.
Areas:
The fo:single-page-master-reference formatting object generates no area directly. It is used by the fo:page-sequence formatting object to generate pages.
Constraints:
The fo:single-page-master-reference has a reference to the fo:simple-page-master which has the same master-name as the master-name trait on the fo:single-page-master-reference.
The sub-sequence of pages mapped to this sub-sequence-specifier satisfies the constraints of this sub-sequence-specifier if (a) the sub-sequence of pages consists of a single page and (b) that page is constrained to have been generated using the fo:simple-page-master referenced by the fo:single-page-master-reference.
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The following properties apply to this formatting object:
Common Usage:
An fo:repeatable-page-master-reference is the next simplest sub-sequence-specifier. It specifies a sub-sequence consisting of repeated instances of a single page-master. The number of repetitions may be bounded or potentially unbounded.
Areas:
The fo:repeatable-page-master-reference formatting object generates no area directly. It is used by the fo:page-sequence formatting object to generate pages.
Constraints:
The fo:repeatable-page-master-reference has a reference to the fo:simple-page-master which has the same master-name as the master-name trait on the fo:repeatable-page-master-reference.
The sub-sequence of pages mapped to this sub-sequence-specifier satisfies the constraints of this sub-sequence-specifier if (a) the sub-sequence of pages consists of zero or more pages, (b) each page is generated using the fo:simple-page-master referenced by the fo:repeatable-page-master-reference, and (c) length of the sub-sequence is less than or equal to the value of maximum-repeats.
If no region-master child of the fo:repeatable-page-master has a region-name associated to any flow in an fo:page-sequence, then the sub-sequence is constrained to have length zero.
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The following properties apply to this formatting object:
Common Usage:
The fo:repeatable-page-master-alternatives formatting object is the most complex sub-sequence-specifier. It specifies a sub-sequence consisting of repeated instances of a set of alternative page-masters. The number of repetitions may be bounded or potentially unbounded. Which of the alternative page-masters is used at any point in the sequence depends on the evaluation of a condition on the use of the alternative. Typical conditions include, testing whether the page which is generated using the alternative is the first or last page in a page-sequence or is the page blank. The full set of conditions allows different page-masters to be used for the first page, for odd and even pages, for blank pages.
NOTE:Because the conditions are tested in order from the beginning of the sequence of children, the last alternative in the sequence usually has a condition that is always true and this alternative references the page-master that is used for all pages that do not receive some specialized layout.
Areas:
The fo:repeatable-page-master-alternatives formatting object generates no area directly. This formatting object is used by the fo:page-sequence formatting object to generate pages.
Constraints:
The children of the fo:repeatable-page-master-alternatives are fo:conditional-page-master-references. These children will be called alternatives.
The sub-sequence of pages mapped to this sub-sequence-specifier satisfies the
constraints of this sub-sequence-specifier if (a) the sub-sequence of pages
consist of zero or more pages, (b) each page is generated using the
fo:simple-page-master referenced by the one of the alternatives that are the
children of the fo:repeatable-page-master-alternatives, (c) the conditions on
that alternative are true, (d) that alternative is the first
alternative in the sequence of children for which all the conditions are
true, and (e) the length of the sub-sequence is less than or equal
to the value of maximum-repeats.
Contents:
(conditional-page-master-reference+)
The following properties apply to this formatting object:
Common Usage:
The fo:conditional-page-master-reference is used to identify a page-master that is to be used when the conditions on its use are satisfied. This allows different page-masters to be used, for example, for even and odd pages, for the first page in a page-sequence, or for blank pages. This usage is typical in chapters of a book or report where the first page has a different layout than the rest of the chapter and the headings and footings on even and odd pages may be different as well.
Areas:
The fo:conditional-page-master-reference formatting object generates no area directly. It is used by the fo:page-sequence formatting object to generate pages.
Constraints:
The fo:conditional-page-master-reference has a reference to the fo:simple-page-master which has the same master-name as the master-name trait on the fo:conditional-page-master-reference.
There are three traits, page-position, odd-or-even, and
blank-or-not-blank that specify the sub-conditions on the use of the
referenced page-master. All three sub-conditions must be true for
the condition on the fo:conditional-page-master-reference to be
true. Since the properties from which these traits are derived are
not inherited and the initial value of all the properties makes the
corresponding sub-condition true, this really means that the subset
of traits that are derived from properties with specified values must make the
corresponding sub-condition true.
The sub-condition corresponding to the page-position trait is
true if the page generated using the
fo:conditional-page-master-reference has the specified position in the sequence
of pages generated by the referencing page-sequence; namely, "first", "last",
"rest" (not first) or "any" (all of the previous). The referencing
page-sequence is the fo:page-sequence that referenced the
fo:page-sequence-master from which this fo:conditional-page-master-reference is
a descendant.
The sub-condition corresponding to the odd-or-even trait is
true if the value of the odd-or-even trait is "any" or if
the value matches the parity of the page number of the page generated using the
fo:conditional-page-master-reference.
The sub-condition corresponding to the blank-or-not-blank trait is
true, if (1) the value of the trait is "not-blank" and the page
generated using the fo:conditional-page-master-reference has areas generated by
descendants of the fo:flow formatting object; if (2) the value of the trait is
"blank" and the page generated using the fo:conditional-page-master-reference is
such that there are no areas from the fo:flow to be put on that page (e.g., (a)
to maintain proper page parity due to (i) a break-after or break-before value of
"even-page" or "odd-page" or (ii) at the start or end of the page-sequence or
(b) because the constraints on the areas generated by descendants of the fo:flow
formatting object would not be satisfied if they were descendant from this
page); or if (3) the value of the trait is "any".
NOTE:If any page-master referenced from a conditional-page-master-reference with blank-or-not-blank="
true" provides a region in which to put fo:flow content, no content is put in that region.
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The following properties apply to this formatting object:
Common Usage:
The fo:simple-page-master is used in the generation of pages and specifies the geometry of the page. The page may be subdivided into up to five regions: region-body, region-before, region-after, region-start, and region-end.
NOTE:For example, if the writing-mode of the fo:simple-page-master is "lr-tb", then these regions correspond to the body of a document, the header, the footer, the left sidebar, and the right sidebar.
NOTE:The simple-page-master is intended for systems that wish to provide a simple page layout facility. Future versions of this recommendation will support more complex page layouts constructed using the fo:page-master formatting object.
Areas:
The fo:simple-page-master formatting object generates no area directly. It is used in the generation of pages by an fo:page-sequence.
When the fo:simple-page-master is used to generate a page, a viewport/reference pair is generated, consisting of a page-viewport-area and a page-reference-area. The page-viewport-area represents the physical bounds of the output medium. The page-reference-area represents the portion of the page on which content is intended to appear; that is, the area inside the page margins.
In addition, when the fo:simple-page-master is used to generate a page, viewport/reference pairs that correspond to the regions that are the children of the fo:simple-page-master are also generated. (See the formatting object specifications for the five regions ([6.4.13 fo:region-body], [6.4.14 fo:region-before], [6.4.15 fo:region-after], [6.4.16 fo:region-start], and [6.4.17 fo:region-end]) for the details on the generation of these areas.)
Region-viewport-areas
The spacing between the outer four regions and the fo:region-body is determined by subtracting the relevant extent trait on each outer region from the "margin-x" property on the fo:region-body.
Trait Derivation:
In version 1.0 of this recommendation, borders and padding are not allowed with a page-reference-area. The remaining traits on the page-reference-area are set according to normal rules for determining the values of traits.
Constraints:
When a page-master is used in the generation of a page, the height and width of the content-rectangle of the page-viewport-area are determined using the computed values of the "page-height" and "page-width" properties.
The traits derived from the margin properties determine the size and position of the content-rectangle of the page-viewport-area. The traits derived from the "margin-top", "margin-bottom", "margin-left" and "margin-right" properties are used to indent the page-reference-area content-rectangle from the corresponding edge of the content-rectangle of the page-viewport-area. Here "top", "bottom", "left" and "right" are determined by the computed values of the "page-height" and "page-width" properties. For sheet media, these values determine the orientation of the sheet; "page-height" is measured from "top" to "bottom". For display media, the display window is always upright; the top of the display screen is "top".
NOTE:The reference points for the page-viewport-area content-rectangle are in terms of the "top", "bottom", "left", and "right" rather than "before-edge",