NeoKolors.Tui.Core 2026.2.0-rc2.2

NeoKolors.Tui.Core

NeoKolors.Tui.Core provides the core double-buffered visual canvas, geometry abstractions, border styles, and screen rendering drivers that power the NeoKolors TUI framework. It manages the low-level visual grid of character cells, tracking styling state changes and outputting compiled ANSI update buffers to the console.

Core Features

• Double-Buffered Grid Canvas:
  • ICharCanvas & NKCharCanvas: Represent a mutable 2D grid containing character cells, styling metadata, and Z-Index depth layers. Can dynamically resize, clear, or lay out nested canvases.
• Console Render Screen:
  • ICharScreen & NKCharScreen: Manage the primary terminal screen state, writing diffed grid segments into a single compiled ANSI escape stream to minimize redraw flicker.
• Customizable Borders:
  • BorderStyle: Models border configurations (top, bottom, left, right sides, and corners) with custom style attributes. Includes built-in parsers and predefined styles (such as Ascii, Normal, Rounded, Thick, Double, Inset, and Outset).
• Canvas Drawing Helpers:
  • CharCanvasExtensions: Extends the base canvas interface to support drawing borders, rectangles, filling background areas, and styling specific regions.
• Sixel Image Support:
  • Directly place pixel images (ISixelImageInfo) onto canvas layer offsets, translating pixel maps into console coordinates.

Core Types and Abstractions

1. ICharCanvas

The interface defining operations for visual grid modification:

• Width / Height / Size: Dimensions of the current canvas.
• this[x, y]: Retrieves or assigns a CellInfo object containing character and style details.
• Place(): Places sub-canvases, character grids, styled strings, or raw character codes at specific offsets and depth layers.
• PlaceSixel(): Allocates an image buffer to be drawn on terminal screens.

2. BorderStyle

Predefined styles for box borders:

• GetAscii(): Prints borders using standard ASCII characters (+, -, |).
• GetRounded(): Uses box-drawing characters featuring rounded corners (╭, ╮, ╰, ╯).
• GetThick() / GetDouble(): Pre-configured thick or double-line box margins.
• GetInset() / GetOutset(): Utilizes shadows and highlights to simulate 3D inset/outset framing.

Usage Examples

1. Drawing Styled Rectangles

Using drawing extensions to draw borders and fill backgrounds:

using Metriks;
using NeoKolors.Common;
using NeoKolors.Tui.Core;

// Create a visual canvas
var canvas = new NKCharCanvas(80, 24);

// Define a region and border style
var region = new Rectangle(new Point2D(5, 2), new Point2D(25, 8));
var border = BorderStyle.GetRounded(NKColor.FromRgb(0, 255, 128));

// Draw the rounded border
canvas.PlaceRectangle(region, border);

// Apply a background color to the inner area
var innerRegion = new Rectangle(new Point2D(6, 3), new Point2D(24, 7));
canvas.StyleBackground(innerRegion, NKColor.FromRgb(32, 32, 32));

2. Rendering the Screen Buffer

Setting up a screen and executing render cycles:

using Metriks;
using NeoKolors.Tui.Core;

var screenSize = new Size2D(120, 40);
var screen = new NKCharScreen(screenSize);

// Draw static text
screen.Place("NeoKolors TUI Core Engine", new Point2D(2, 1));

// Render changes to the console stream
screen.Render();