Struct LayoutEngine 

pub struct LayoutEngine { /* private fields */ }

Layout engine - manages visual representation of all lines

Implementations

impl LayoutEngine

pub fn new(viewport_width: usize) -> Self

Create a new layout engine

pub fn set_viewport_width(&mut self, width: usize)

Set viewport width

pub fn viewport_width(&self) -> usize

Get viewport width

pub fn tab_width(&self) -> usize

Get tab width (in cells).

pub fn set_tab_width(&mut self, tab_width: usize)

Set tab width (in cells) used for expanding '\t'.

If tab_width changes, all line layouts are recalculated.

pub fn from_lines(&mut self, lines: &[&str])

Build layout from list of text lines

pub fn add_line(&mut self, text: &str)

Add a line

pub fn update_line(&mut self, line_index: usize, text: &str)

Update a specific line

pub fn insert_line(&mut self, line_index: usize, text: &str)

Insert a line

pub fn delete_line(&mut self, line_index: usize)

Delete a line

pub fn get_line_layout(&self, line_index: usize) -> Option<&VisualLineInfo>

Get visual information for a specific logical line

pub fn logical_line_count(&self) -> usize

Get total number of logical lines

pub fn visual_line_count(&self) -> usize

Get total number of visual lines

pub fn logical_to_visual_line(&self, logical_line: usize) -> usize

Convert logical line number to visual line number

Returns the line number of the first visual line of this logical line

pub fn visual_to_logical_line(&self, visual_line: usize) -> (usize, usize)

Convert visual line number to logical line number and offset within line

Returns (logical_line, visual_line_in_logical)

pub fn clear(&mut self)

Clear all lines

pub fn logical_position_to_visual( &self, logical_line: usize, column: usize, ) -> Option<(usize, usize)>

Convert logical coordinates (line, column) to visual coordinates (visual row number, x cell offset within row).

• logical_line: Logical line number (0-based)
• column: Character column within the logical line (0-based, counted by char)

Return value:

• Some((visual_row, x)): visual_row is the global visual row number, x is the cell offset within that visual row
• None: Line number out of range

pub fn logical_position_to_visual_allow_virtual( &self, logical_line: usize, column: usize, ) -> Option<(usize, usize)>

Convert logical coordinates (line, column) to visual coordinates, allowing column to exceed line end (virtual spaces).

Difference from logical_position_to_visual:

• column is not clamped to line_char_len
• Excess portion is treated as virtual spaces of ' ' (width=1)