the area tree must be minimal and independant. This means that the data
uses less memory and can be serialized to an output stream if needed.
</p>
+<p>The Area Tree is an internal representation of the result document. This
+is a set of java classes that can put together a set of objects that
+represent the pages and their contents.</p>
+<p>This information is created by the layout managers and is rendered to the
+output using a renderer.</p>
+<p>The Area Tree follows the description of the area tree in the XSL:FO
+specification.</p>
+<p>The Area Tree consists of a set of pages, the actual implemenation places
+these in
+a set of page sequences.</p>
<section>
<title>Structure</title>
<p>
</section>
<section>
<title>Page</title>
-<p>
+<p>A page consists of a page+viewport pair.</p>
+<p>The PageViewPort and Page with the regions is created by the
+LayoutMasterSet. The contents are then placed by the layout managers. Once
+the layout of a page is complete then it is added to the Area Tree.</p>
+<p>Inside the page is a set of RegionViewport+Region pairs for each region on
+the page.</p><p>
A page is made up of five area regions. These are before, start, body,
end and after. Each region has a viewport and contains the areas
produced from the children in the FO object heirarchy.
</section>
<section>
<title>Block Areas</title>
+<p>Block level areas contain either other blocks or line areas (which is a
+special block area).</p><p>
+A block is either positoned or stacked with other block areas.</p>
<p>
Block areas are created and/or returned by all top level elements
in the flow. The spacing between block areas is handled by an
sizes once it is resolved. Then the line can be re-justified
and finalised.
</p>
+<p>Inline areas are stacked in a line area. Inline areas are objects such as
+character, viewport, inline-container, leader and space. A special inline
+area Word is also used for a group of consecutive characters.</p>
+<p>The image and instream foreign object areas are placed inside a viewport.
+The leader (with use content) and unresolved page number areas are
+resolved to other inline areas.</p>
+<p>Once a LineArea is filled with inline areas then the inline areas need to
+be aligned and adjusted to fill the line properly.</p>
</section>
<section>
<title>Repeated Areas</title>
static areas, table header/footer, svg.
</p>
</section>
+<section>
+ <title>Traits</title>
+
+<p>A trait is information associated with an area. This could be information
+such as text colour or is-first.</p>
+<p>Traits provide information about an area. The traits are derived from
+properties on the formatting object or are generated during the layout
+process. Many of the layout traits do not have actual values but can be
+derived from the Area Tree. Other traits that apply when rendering the
+areas are set on the area. Since setting the same value on every area
+would use a lot of memory then the traits are derived from default or
+parent values.</p>
+<p>A dominant trait on a block area is set, for example font colour, so that
+every line area with the same dominant value can derive it. The text
+inline areas then get the font colour set on the inline area or from the
+line area or from the block area.</p>
+</section>
<section>
<title>Classes</title>
<p>
</section>
</section>
+<section>
+ <title>Forward References</title>
+<p>The Area Tree maintains a set of mappings from the reference to pages.</p>
+<p>The PageViewPort holds the list of forward references that need resolving
+so that if a references is resolved during layout the page can be easily
+found and then fixed. Once all the forward references are resolved then
+the page is ready to be rendered.</p>
+<p>To layout a page any areas that cannot be resolved need to reserve space.
+Once the inline area is resolved then the complete line should be adjusted
+to accomodate any change in space used by the area.</p>
+</section>
+
+<section>
+ <title>Caching</title>
+<p>We may need to cache pages due to forward references or when keeping all
+pages.</p>
+<p>This is done by serializing the Page. The PageViewport is retained to be
+used as a key for page references and backward references.
+The Page is serialized to an object stream and then all of the page
+contents are released. The Page is then recoved by reading from the object
+stream.</p>
+<p>The PageViewport retains information about id areas for easy access.</p>
+</section>
+
+<section>
+ <title>Extensions</title>
+<p>The Area Tree holds the Output Document extensions. This is information
+such as pdf bookmarks or other output document specific information that
+is not handled by XSL:FO.</p>
+<p>It is also possible to create custom areas that extend a normal area. The
+actual data that is rendered could be set in a different way or depend on
+resolving a forward reference.</p>
+</section>
+
+<section>
+ <title>Area Tree Handlers</title>
+<p>To handle different situations the handler for the Area Tree handles each
+page as it is added.</p><p>
+The RenderPagesModel sends the page directly to the renderer if the page
+is ready to be rendered. Once a page is rendered it is discarded.
+The StorePagesModel stores all the pages so that any page can be later
+accessed.</p>
+<p>The Area Tree retains the concept of page sequences (this is not in the
+area tree in the spec) so that this information can be passed to the
+renderer. This is useful for setting the title and organising the groups
+of page sequences.</p>
+</section>
+
<section>
<title>Rendering Area Tree</title>
<p>
+++ /dev/null
-<?xml version="1.0" standalone="no"?>
-<!DOCTYPE document PUBLIC "-//APACHE//DTD Documentation V1.1//EN"
- "http://cvs.apache.org/viewcvs.cgi/*checkout*/xml-forrest/src/resources/schema/dtd/document-v11.dtd">
-
-<document>
- <header>
- <title>Area Tree</title>
- </header>
-
- <body>
-<section>
- <title>Area Tree</title>
-<p>The Area Tree is an internal representation of the result document. This
-is a set of java classes that can put together a set of objects that
-represent the pages and their contents.</p>
-<p>This information is created by the layout managers and is rendered to the
-output using a renderer.</p>
-<p>The Area Tree follows the description of the area tree in the XSL:FO
-specification.</p>
-<p>The Area Tree consists of a set of pages, the actual implemenation places
-these in
-a set of page sequences.</p>
-</section>
-
-<section>
- <title>Pages</title>
-<p>A page consists of a page+viewport pair.</p>
-<p>The PageViewPort and Page with the regions is created by the
-LayoutMasterSet. The contents are then placed by the layout managers. Once
-the layout of a page is complete then it is added to the Area Tree.</p>
-<p>Inside the page is a set of RegionViewport+Region pairs for each region on
-the page.</p></section>
-
-
-<section>
- <title>Blocks</title>
-<p>Block level areas contain either other blocks or line areas (which is a
-special block area).</p><p>
-A block is either positoned or stacked with other block areas.</p>
-</section>
-
-<section>
- <title>Inline Areas</title>
-<p>Inline areas are stacked in a line area. Inline areas are objects such as
-character, viewport, inline-container, leader and space. A special inline
-area Word is also used for a group of consecutive characters.</p>
-<p>The image and instream foreign object areas are placed inside a viewport.
-The leader (with use content) and unresolved page number areas are
-resolved to other inline areas.</p>
-<p>Once a LineArea is filled with inline areas then the inline areas need to
-be aligned and adjusted to fill the line properly.</p>
-</section>
-
-<section>
- <title>Traits</title>
-
-<p>A trait is information associated with an area. This could be information
-such as text colour or is-first.</p>
-<p>Traits provide information about an area. The traits are derived from
-properties on the formatting object or are generated during the layout
-process. Many of the layout traits do not have actual values but can be
-derived from the Area Tree. Other traits that apply when rendering the
-areas are set on the area. Since setting the same value on every area
-would use a lot of memory then the traits are derived from default or
-parent values.</p>
-<p>A dominant trait on a block area is set, for example font colour, so that
-every line area with the same dominant value can derive it. The text
-inline areas then get the font colour set on the inline area or from the
-line area or from the block area.</p>
-</section>
-
-<section>
- <title>Forward References</title>
-<p>The Area Tree maintains a set of mappings from the reference to pages.</p>
-<p>The PageViewPort holds the list of forward references that need resolving
-so that if a references is resolved during layout the page can be easily
-found and then fixed. Once all the forward references are resolved then
-the page is ready to be rendered.</p>
-<p>To layout a page any areas that cannot be resolved need to reserve space.
-Once the inline area is resolved then the complete line should be adjusted
-to accomodate any change in space used by the area.</p>
-</section>
-
-<section>
- <title>Caching</title>
-<p>We may need to cache pages due to forward references or when keeping all
-pages.</p>
-<p>This is done by serializing the Page. The PageViewport is retained to be
-used as a key for page references and backward references.
-The Page is serialized to an object stream and then all of the page
-contents are released. The Page is then recoved by reading from the object
-stream.</p>
-<p>The PageViewport retains information about id areas for easy access.</p>
-</section>
-
-<section>
- <title>Extensions</title>
-<p>The Area Tree holds the Output Document extensions. This is information
-such as pdf bookmarks or other output document specific information that
-is not handled by XSL:FO.</p>
-<p>It is also possible to create custom areas that extend a normal area. The
-actual data that is rendered could be set in a different way or depend on
-resolving a forward reference.</p>
-</section>
-
-<section>
- <title>Area Tree Handlers</title>
-<p>To handle different situations the handler for the Area Tree handles each
-page as it is added.</p><p>
-The RenderPagesModel sends the page directly to the renderer if the page
-is ready to be rendered. Once a page is rendered it is discarded.
-The StorePagesModel stores all the pages so that any page can be later
-accessed.</p>
-<p>The Area Tree retains the concept of page sequences (this is not in the
-area tree in the spec) so that this information can be passed to the
-renderer. This is useful for setting the title and organising the groups
-of page sequences.</p>
-</section>
-
- </body>
-</document>
-
projects / xmlgraphics-fop.git / commitdiff