Data Structures

Data Structures

Namespace: ParentElement.RichText.Core.Data

Lightweight value types used to configure the document, communicate size changes, and describe the current navigation state.

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DocumentSettings

Controls the document page layout and default formatting. Pass an instance to the DocumentController constructor and use ApplyDocumentSettings to update it at runtime.

public struct DocumentSettings

Properties

Property	Type	Default	Description
PageWidth	float	800	Width of the document page in pixels
PageHeight	float	1056	Height of one page in pixels (US Letter @ 96 dpi)
PageGap	float	24	Vertical gap between pages when page breaks are shown
DocumentMargins	DocumentMargins	default	Inner margins applied within the page boundary
DocumentBackgroundColor	SKColor	White	Background color of the page area
CanvasBackgroundColor	SKColor	#E8E8E8	Background color of the canvas surrounding the page
TextStyle	IStyle	DefaultStyle	Default character style for new text
Alignment	TextAlignment	Left	Default paragraph alignment
ShowPageBreaks	bool	false	Whether to render a visual page separator

Example

var settings = new DocumentSettings
{
    PageWidth            = 816,   // US Letter at 96 dpi
    PageHeight           = 1056,
    ShowPageBreaks       = true,
    DocumentMargins      = new DocumentMargins(72, 72, 72, 72),
    DocumentBackgroundColor = SKColors.White,
    CanvasBackgroundColor   = new SKColor(0xE8, 0xE8, 0xE8),
};

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DocumentMargins

Defines the inner margins of the document page.

public struct DocumentMargins

Constructor

public DocumentMargins(float left, float right, float top, float bottom)

Properties

Property	Type	Description
Left	float	Left margin in pixels
Right	float	Right margin in pixels
Top	float	Top margin in pixels
Bottom	float	Bottom margin in pixels

Example

// 0.75-inch margins at 96 dpi
var margins = new DocumentMargins(left: 72, right: 72, top: 72, bottom: 72);

// Object-initializer syntax
var margins = new DocumentMargins { Left = 40, Right = 40, Top = 24, Bottom = 24 };

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DocumentInfo

Snapshot of the document's current dimensions and scroll position. Delivered via the IDocumentController.OnContentSizeChanged event.

public struct DocumentInfo

Constructor

public DocumentInfo(float width, float height, Vector2 scrollOffset)

Fields

Field	Type	Description
Width	float	Document page width in pixels
Height	float	Total rendered content height in pixels
ScrollOffset	Vector2	Current scroll position of the viewport

Example

editor.OnContentSizeChanged += info =>
{
    scrollbar.Maximum = info.Height;
    scrollbar.Value   = info.ScrollOffset.Y;
};

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NavigationInfo

Snapshot of the caret position, selection, and style. Delivered via the IDocumentController.OnNavigation event every time the caret moves or the selection changes.

public struct NavigationInfo

Constructor

public NavigationInfo(TextRange selection, IStyle styleAtCaret, SelectionInfo selectionInfo)

Properties

Property	Type	Description
Selection	TextRange	The current selection range within the document
StyleAtCaret	IStyle	Resolved character style at the caret position
SelectionInfo	SelectionInfo	Detailed selection metadata (word, paragraph boundaries)

Example

editor.OnNavigation += info =>
{
    // Sync toolbar state
    boldButton.IsChecked   = info.StyleAtCaret.Bold ?? false;
    italicButton.IsChecked = info.StyleAtCaret.Italic ?? false;
    fontPicker.Value       = info.StyleAtCaret.FontFamily ?? "Arial";
    sizePicker.Value       = (int)(info.StyleAtCaret.FontSize ?? 12);

    // Update status bar
    statusBar.Text = info.SelectionInfo.IsSelection
        ? $"{info.SelectionInfo.Length} characters selected"
        : "Ready";
};

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ViewModifier

A combined scale + offset transform applied when converting pointer (screen) coordinates to document coordinates.

public struct ViewModifier

Properties

Property	Type	Access	Description
Scale	Vector2	get / set	Zoom scale. Setting this recomputes ScaledOffset
Offset	Vector2	get / set	Pixel scroll offset. Setting this recomputes ScaledOffset
ScaledOffset	Vector2	get	Offset / Scale — pre-divided for efficient coordinate transforms

How It Works

Point.FromView(ViewModifier) uses ScaledOffset to transform a screen-space point into document space:

documentX = screenX / scale.X + scaledOffset.X
documentY = screenY / scale.X + scaledOffset.Y

Example

var view = new ViewModifier
{
    Scale  = new Vector2(zoomFactor, zoomFactor),
    Offset = new Vector2(scrollX, scrollY),
};

var docPoint = screenPoint.FromView(view);
editor.Click(docPoint);

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See also: IDocumentController · Geometry