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diff --git a/docs/design/areas.xml b/docs/design/areas.xml deleted file mode 100644 index 11e991834..000000000 --- a/docs/design/areas.xml +++ /dev/null @@ -1,192 +0,0 @@ -<?xml version = "1.0" encoding = "UTF-8"?> -<section id="areatree"> - <title>Area Tree</title> - <para> -The code to implement the area tree will attempt to match the areas -defined in the specification. A number of optimisations may be possible -for similar areas and groups of areas. - </para> - <para> -Since the area tree will be used during the layout by the layout managers -it will need to store information that affects the layout. The information -such as spacing and keeps will be held in such a way that it can be -discarded once the layout is finalised. - </para> - -<section> - <title>The Area Tree</title> - <para> -The area tree is a root element that has a list of page-viewport-areas. -Each page viewport has a page-reference-area which holds the contents of -the page. To handle the processing better FOP does not maintain a list -at the root level but lets another class handle each page as it is added. - </para> -</section> - -<section> - <title>Page</title> - <para> -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. - </para> - <para> -For the body area there are more subdivisions for before floats, -footnotes and the main reference area. The main reference area is -made from span areas which have normal flow reference areas as -children. The flow areas are then created inside these normal flow -reference areas. - </para> - <para> -Since the layout is done inside a page, the page is created from the -pagemaster with all the appropriate areas. The layout manager then -uses the page to add areas into the normal flow reference areas -and floats and footnotes. After the layout of the body region -is complete then the other regions can be done. - </para> -</section> - -<section> - <title>Block Areas</title> - <para> -Block areas are created and/or returned by all top level elements -in the flow. These areas have keep and spacing information that -needs to be retained until the page is finalised. A block area -is stacked with other block areas in a particular direction, it -has a size and it contains either line areas made from a group -of inline areas or block areas. - </para> - <para> -A block area can also be split into two block areas by splitting -between two line areas or splitting between two block areas (or -groups) that are stacked in the block progression direction of -the page. The split may also be in a child block area. - </para> -</section> - -<section> - <title>Line Areas</title> - <para> -A line areas is simply a collection of inline areas that are stacked -in the inline progression direction. A line area has a height and -width. It also contains information about floats and footnotes -that are associated with the inline areas. - </para> - <para> -A line area gets a set of inline areas added until complete then -it is justified and vertically aligned. If the line area contains -unresolved areas it will retain the justification information -until all areas are resolved. - </para> -</section> - -<section> - <title>Inline Areas</title> - <para> -There are a few different types of inline areas. All inline areas -have a height. Their width may be variable until the line is -finalised. - </para> - <para> -Unresolved areas can reserve some space to allow for possible -sizes once it is resolved. Then the line can be re-justified -and finalised. - </para> -</section> - -<section> - <title>Cloning</title> - <para> -Any subtree of the area tree should be cloneable so that for -areas that are repeated the area tree can simply be copied rather -than going through the layout again. This will only work if the -width is the same. - </para> - <para> -Resolveable areas may be converted into an unresolved form. - </para> -</section> - -<section> - <title>Classes</title> - <para> -The following class structure will be used to represent the area -tree. - </para> - <para> - - </para> -<section> - <title>Page Area Classes</title> - <para> -The page area classes hold the top level layout of a page. The -areas are created by the page master and should be ready to have -flow areas added. - </para> -</section> -<section> - <title>Block Area Classes</title> - <para> -The block areas typically hold either a set of line areas or a set of -block areas. The child areas are usually stacked in a particular -direction. - </para> - <para> -Areas for tables and lists have their child block areas stacked -in different ways. Lists also can have spacing between the block -areas. - </para> -</section> -<section> - <title>Inline Area Classes</title> - <para> -The inline areas are used to make up a line area. An inline area -typically has a height, width and some content. The alignment is -used for block progression direction displacement and to determine -the height of a line. - </para> -</section> - -</section> - -<section> - <title>Rendering Area Tree</title> - <para> -The rendering of an area tree is done by rendering each page -to a suitable output. The regions are rendered in order and each -region is contained by a viewport. - </para> - <para> -The relevent structures that will need to be rendered are: -Page -Viewport -Region -Span -Block -Line -Inline - </para> - <para> -The renderer will need to be able to: - <itemizedlist> - <listitem><para> -render each individual page - </para></listitem> - <listitem><para> -clip and align child areas to a viewport - </para></listitem> - <listitem><para> -handle all types of inline area, text, image etc. - </para></listitem> - <listitem><para> -draw various lines and rectangles - </para></listitem> - </itemizedlist> - </para> - <para> -An abstract renderer will be able to handle the generic positioning -of child areas, iterating through areas that have child areas. - </para> -</section> - -</section> |