Overview The ZepWindow class represents a single pane displaying a buffer. It manages the visual presentation of text, including cursor positioning, scrolling, line layout, syntax highlighting display, and user interactions like mouse events. Multiple windows can display the same buffer with independent cursor positions and scroll states.
Constructor ZepWindow ZepWindow (ZepTabWindow & window, ZepBuffer * buffer);
Parent tab window that contains this window
Buffer to display in this window
Create a new window displaying the specified buffer.
Display Management Display Render the window content, including text, cursor, line numbers, scrollbars, and markers.
SetDisplayRegion virtual void SetDisplayRegion ( const NRectf & region );
Rectangle defining the window’s display area
Set the screen region where this window should be displayed.
Buffer Management GetBuffer virtual ZepBuffer & GetBuffer () const ;
Get the buffer displayed in this window.
SetBuffer virtual void SetBuffer ( ZepBuffer * pBuffer );
Change the buffer displayed in this window.
Cursor Management GetBufferCursor virtual GlyphIterator GetBufferCursor ();
Get the current cursor position in buffer coordinates.
SetBufferCursor virtual void SetBufferCursor ( GlyphIterator location );
New cursor position in the buffer
Set the cursor to a specific buffer location. The window will scroll to make the cursor visible.
MoveCursorY virtual void MoveCursorY ( int yDistance , LineLocation clampLocation = LineLocation :: LineLastNonCR );
Number of lines to move (positive = down, negative = up)
Where to clamp cursor horizontally when moving between lines (default: LineLastNonCR)
Move the cursor vertically by the specified number of lines.
BufferToDisplay virtual NVec2i BufferToDisplay ();
Convert the current buffer cursor position to display coordinates. Returns the (x, y) position on screen.
Window Flags SetWindowFlags virtual void SetWindowFlags ( uint32_t windowFlags );
Flags from WindowFlags enum:
None (0): No special flagsShowWhiteSpace (1 << 0): Show whitespace charactersShowCR (1 << 1): Show carriage return charactersShowLineNumbers (1 << 2): Display line numbersShowIndicators (1 << 3): Show indicator columnHideScrollBar (1 << 4): Hide the scrollbarModal (1 << 5): Window is modalWrapText (1 << 6): Enable text wrapping (experimental)HideSplitMark (1 << 7): Hide split window markerGridStyle (1 << 8): Use grid-style display Set window display flags.
GetWindowFlags virtual uint32_t GetWindowFlags () const ;
Get the current window flags.
ToggleFlag virtual void ToggleFlag ( uint32_t flag );
Toggle a specific window flag on or off.
GetMaxDisplayLines virtual long GetMaxDisplayLines ();
Get the maximum number of lines that can be displayed in the window viewport.
GetNumDisplayedLines virtual long GetNumDisplayedLines ();
Get the actual number of lines currently being displayed.
Parent Tab Window GetTabWindow ZepTabWindow & GetTabWindow () const ;
Get the parent tab window that contains this window.
Color and Theme FilterActiveColor NVec4f FilterActiveColor ( const NVec4f & col , float atten = 1.0 f );
Attenuation factor (default: 1.0)
Filter a color based on whether this window is active. Inactive windows have dimmed colors.
Layout Management DirtyLayout Mark the window layout as needing recalculation. Call this when buffer content changes or window size changes.
Window Regions The window is divided into several internal regions:
Show Internal Region Structure
Buffer Region : Overall window areaEdit Region : Area where editing occursText Region : Region containing actual text contentAirline Region : Status line at bottom of windowNumber Region : Line numbers columnIndicator Region : Indicator column between numbers and text (for breakpoints, etc.)Vertical Scroll Region : Scrollbar areaExpanding Edit Region : Container for text with flexible sizing Cursor Types Windows support different cursor display modes:
enum class CursorType { None , // No cursor displayed Normal , // Normal mode cursor (block) Insert , // Insert mode cursor (line) Visual , // Visual mode cursor (selection) LineMarker // Line marker cursor };
The window calculates SpanInfo structures for each displayed line:
struct SpanInfo { ByteRange lineByteRange; // Start/end in buffer std ::vector < LineCharInfo > lineCodePoints; // Character positions long bufferLineNumber; // Original buffer line number float yOffsetPx; // Pixel Y offset NVec2f lineTextSizePx; // Size of text in pixels int spanLineIndex; // Index in span list NVec2f padding; // Line padding bool isSplitContinuation; // True if wrapped line NVec2f lineWidgetHeights; // Height of line widgets ZepFont * pFont; // Font for this line float FullLineHeightPx () const ; // Total line height long ByteLength () const ; // Line byte length bool BufferCursorInside ( GlyphIterator offset ) const ; };
Airline Status Bar Windows can display an “airline” status bar showing buffer information:
struct Airline { std ::vector < AirBox > leftBoxes; // Left-aligned status boxes std ::vector < AirBox > rightBoxes; // Right-aligned status boxes }; struct AirBox { std ::string text; // Box text content NVec4f background; // Box background color };
Windows support displaying tooltips for markers (errors, warnings, etc.):
struct ToolTipMessage : public ZepMessage { ZepBuffer * pBuffer; // Buffer containing the marker GlyphIterator location; // Location in buffer std ::shared_ptr < RangeMarker > spMarker; // The marker to display };
Usage Example #include <zep/window.h> #include <zep/tab_window.h> #include <zep/buffer.h> // Create tab window and buffer ZepTabWindow * pTabWindow = editor . AddTabWindow (); ZepBuffer * pBuffer = editor . GetFileBuffer ( "main.cpp" ); // Create window ZepWindow window ( * pTabWindow , pBuffer ); // Configure window window . SetWindowFlags ( WindowFlags ::ShowLineNumbers | WindowFlags ::ShowIndicators | WindowFlags ::ShowWhiteSpace); // Set display region NRectf region ( 0 , 0 , 800 , 600 ); window . SetDisplayRegion (region); // Set cursor position GlyphIterator pos = pBuffer -> Begin (); window . SetBufferCursor (pos); // Move cursor down 10 lines window . MoveCursorY ( 10 ); // Display the window window . Display (); // Check if window is active if ( editor . GetActiveWindow () == & window) { // This window is active } // Toggle line numbers window . ToggleFlag ( WindowFlags ::ShowLineNumbers);
Display Passes The window renders in multiple passes:
Background pass : Line backgrounds, selections, cursor lineText pass : Actual text with syntax highlightingDecoration pass : Whitespace indicators, special charactersOverlay pass : Scrollbars, line numbers, markersTooltip pass : Hover tooltips for errors/warnings
Windows cache line span information to avoid recalculation
Only visible lines are rendered
Layout is marked dirty only when necessary
Syntax highlighting is performed incrementally
Scrolling uses pixel offsets for smooth movement
