1.167.1 Instance variables

text_image-change_start: alien:int

Start of changes (character index).

text_image-inserted: alien:int

How much text was inserted/deleted.

text_image-change_end: alien:int

These variables are used by text_image->compute to determine the range of the text that should be updated and the area of the text_image<-image that is to be repainted.

text_image-scan: alien:ScanFunction

C-Function to scan for a syntactical category.

text_image-seek: alien:SeekFunction

C-Function to seek to a position.

text_image-fetch: alien:FetchFunction

C-function pointers obtained from the text_image<-text to perform the following low-level action:

-fetch	Read next character with attributes
-seek	Set index for next -fetch operation
-scan	Scan for a syntactical category

text_image-map: alien:TextScreen

Array of line descriptions. Each line describes a screen-line: character index for the start, displayed characters, fonts, colours and attributes. This map is updated by text_image->compute. See also text_image->dump_map.

text_image-start: int

Start is normally the start of a line of the underlying text (e.i. the first character after a newline character). It will be made the text_image<-start of the text_image. SkipLines is the number of screen lines to omit and may be used to start the screen in the middle of a wrapped long line. The default skip_lines is 0.

text_image<-start returns the character index for the first character of the nth (1-based) screenline. By default this is the first visible character.

text_image <- tab_stops: vector*

Vector of tab-stops in pixels. When defined, this overrules text_image<->tab_distance.

text_image <- text: object

Holder of the text. The text should implement:

text_image<-_seek_function	get -seek function
text_image<-_scan_function	get -scan function
text_image<-_fetch_function	get -fetch function

Besides this, it should notify changes to the text_image object using:

text_image->_changed_region	Indicate text in region has changed
text_image->_insert	Indicate insert/delete

This functionality is currently reserved for the C-programmer.