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= Analysis =

== Overview ==
 * The ability of text to wrap around objects.
  * The objects could wrap the text as follows:
   * none - text is not wrapped
   * before - text wraps only from the left side
   * after - text wraps only from the left side
   * parallel - text wraps from both sides
  * Default value should be parallel.
  * Text will be flowed around intersecting (overlapping) objects (frames, etc.)
  * The way of wrapping will depend on the available space for flowing of the text around the intersecting (overlapping) objects.
   * The following strategy will be considered
    * Flowing text line by line.
     * Text alignment should not be taken into account on the text sides displayed around the overlapping object.

     [[Image(source:branches/private/vlado/sophie2-platform/doc/spec-diagrams/LineByLineTextFlowing.png)]]
    * Flowing text on intersection blocks will not be used in Sophie 2.0. If such functionality is desired it can be mimicked by creation of separate Frames.
     [[Image(source:branches/private/vlado/sophie2-platform/doc/spec-diagrams/IntersectionBlockTextFlowing.png)]]
   * A kind of priority (weight) will be present to estimate the different options for text layout in various cases of intersection (overlapping).
 * Text layout inside a Frame.
  * Text is divided into the following parts which define scopes for the text elements:
   * Text - the whole flowing text.
   * Text Part - part of the whole text, that is displayed as content of a Frame.
   * Line - one line of visible text inside a Frame. It is composed of one or more line segments, depending on intersection with other objects (frames, etc.)
   * Segment (Line Part) - part of a line wrapped around two objects, object and border or two borders of the container Frame.

== Task requirements ==
 * Refine the existing text layout algorithm.
 * Provide layout functionality for accurate calculation of Text Parts depending on the present Frames (needed for [wiki:TEXT_CHAINING_BEHAVIOUR_R0] and [wiki:TEXT_AUTO_CHAIN_BEHAVIOUR_R0]).
 * Fixing a known bug with layout algorithm specified at [http://www.sophie2.org/trac/wiki/TEXT_INPLACE_EDITOR_R0#Implementation].
 * If there is time a simple line by line text flowing will be added.

== Task result ==
The result should be source code.

== Implementation idea ==
 * Hill climbing algorithm is used for laying out text (a general implementation is already present).
  * Check [http://en.wikipedia.org/wiki/Hill_climbing Hill Climbing Algorithm at Wikipedia] for more information.
  * The roles in the algorithm for the purpose of HotTextLayout:
   * Vertex - a collection of vertex fields, such as text range (a specific Segment) and its supported properties (scope, area, position properties, etc.) 
   * Edge - represents a placement (positioning) operation for the next Segment depending on the previous Segment (it is the concrete kind of transition from a Vertex to one of its neighboring Vertex-s)
   * Path - represents a layout of some text (group of Segments, Line or Text Part) with a calculated weight, or "badness" (it is a collection of edges defining the path from one Vertex to another).
  * The goal is to layout the text according to the Path with lowest weight ("badness").
 * The algorithm can be extended with:
  * a better separation of Segments in relation to the needs of wrapping functionality.
  * a better Segment handling and calculations

== Related ==

[wiki:TEXT_CHAINING_BEHAVIOUR_R0]

[wiki:TEXT_AUTO_CHAIN_BEHAVIOUR_R0]

[wiki:SCENE_COMMONS]

[wiki:SCENE_COMMONS_R0]

[wiki:SMOOTH_TEXT_RENDERING_R0]

== How to demo ==
 * A simple line by line text flowing demo (if implemented)
  * Start the application
  * Create new book
  * Inside the book create new text frame and type some text (you could use lorem ipsum generator for better result - http://www.lipsum.com/)
  * Place another frame on top of the text frame. The text should be flowed around the second frame.

= Design =

= Implementation =
^(Describe and link the implementation results here (from the wiki or the repository).)^

= Testing =

= Comments =
^(Write comments for this or later revisions here.)