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	1
	2	wxRichTextCtrl README
	3	=====================
	4
	5	Welcome to wxRichTextCtrl. It includes the following functionality:
	6
	7	* Text entry, paragraph wrapping
	8
	9	* Scrolling, keyboard navigation
	10
	11	* Application of character styles:
	12
	13	bold, italic, underlined, font face, text colour
	14
	15	* Application of paragraph styles:
	16
	17	left/right indentation, sub-indentation (first-line indent),
	18	paragraph spacing (before and after), line spacing,
	19	left/centre/right alignment, numbered bullets
	20
	21	* Insertion of images
	22
	23	* Copy/paste
	24
	25	* Undo/Redo with optional batching and undo history suppression
	26
	27	* Named paragraph and character styles management and application
	28
	29	* File handlers allow addition of file formats
	30
	31	* Text saving and loading, XML saving and loading, HTML saving (unfinished)
	32
	33	Sorry, this is a Windows-only demo for now but the code should
	34	compile on other platforms.
	35
	36	Design
	37	======
	38
	39	Data is represented by a hierarchy of objects, all derived from
	40	wxRichTextObject.
	41
	42	The top of the hierarchy is the buffer, a kind of wxRichTextParagraphLayoutBox.
	43	These boxes will allow flexible placement of text boxes on a page, but
	44	for now there will be a single box representing the document,
	45	and this box will a wxRichTextParagraphLayoutBox which contains further
	46	wxRichTextParagraph objects, each of which can include text and images.
	47
	48	Each object maintains a range (start and end position) measured
	49	from the start of the main parent box.
	50	A paragraph object knows its range, and a text fragment knows its range
	51	too. So, a character or image in a page has a position relative to the
	52	start of the document, and a character in an embedded text box has
	53	a position relative to that text box. For now, we will not be dealing with
	54	embedded objects but it's something to bear in mind for later.
	55
	56	Before display, a changed buffer must have Layout() called on it,
	57	to do wrapping, alignment etc. Ranges representing wrapped lines are stored
	58	with each paragraph.
	59
	60	Since wxRichTextBuffer is separate from wxRichTextCtrl, the storage
	61	and rendering facilities can be used by other controls.
	62
	63	API
	64	===
	65
	66	It's basically the wxTextCtrl with some additions. There is a new
	67	wxTextAttrEx class deriving from wxTextAttr, to accomodate new
	68	style attributes. This could be merged with wxTextAttr. There
	69	is also a wxRichTextAttr which is similar to wxTextAttrEx but
	70	doesn't store the font as a wxFont: this allows much more
	71	efficient operations, especially when querying styles in a
	72	UI update handler. We would not want to create several new wxFonts
	73	when querying for italics, bold, etc. every few milliseconds.
	74
	75	See "Functionality specific to wxRichTextCtrl" section in richtextctrl.h.
	76
	77	One addition is Set/GetBasicStyle, which is needed in addition to
	78	Set/GetDefaultStyle to get the overall style for the buffer
	79	from which content will inherit (after apply the default style).
	80
	81	wxRichTextRange is a new class representing start and end positions.
	82	It's used in the implementation so that pieces of content
	83	know their range, and also in the API in preference to using
	84	two positions.
	85
	86	What next?
	87	==========
	88
	89	- Decision about where to put it: wxCode, wxWidgets
	90	- Makefiles/bakefiles
	91	- Refining the API
	92	- Documentation
	93	- Bug fixing/improvements
	94
	95
	96	See todo.txt for a list of bugs, improvements and features,
	97	and also TODO throughout the source.
	98
	99	==
	100	Julian Smart, October 18th 2005