Terminal UIKit

Swift native UIKit for the terminal with functionality similar to ncurses.

Status

Objective

• Implement a cross platform native Swift implementation of ncurses with a simpler and full featured API.
• Implement a UI element and extended widget API.

Planned Goals

• Support multiple render modes:
  • Character: ASCII, Unicode and Drawille (braille).
  • Color: Mono, 16 Color, 256 Color and RGB
• UI Elements: View, Button, Label, Rich Text Label
• Line graphics: Pixel, Line, Arc, Ellipse, Rectangle, Rounded Rectangle, Pie, Polygon, Polyhedron, Star

TUICharacter

TUICharacter is a foundational UI element built to support:

• Multiple symbol types: Unicode character or Drawille (braille pixels).
• Rendering options:
  • Color: Mono, 16 Color, 256 Color and RGB.
  • Character: Color Intensity and Braille value character ramp (details below)
• "Rich Text" Support: mix of Ansi Color and Attributes.
• Caching of rendered Ansi.

TUICharacter supports either a fixed unicode character or scalar value which encodes 2x4 (x, y) pixels as a single braille character. In this way collections of TUICharacters can intermix a variety of braille pixels with unicode text.

TUICharacter Rendering

Multiple rendering styles are supported for braille pixel encoded values:

• Drawille: Renders as braille pixels
• Short: Short ASCII ramp (paulbourke.net) using color intensities.
• Short2: Short ASCII ramp (iJoshSmith) using color intensities.
• Long: Long ASCII ramp (www.ludd.luth.se) using color intensities.
• DitherShort: Short ASCII ramp using braille values.
• DitherLong: Long ASCII ramp using braille values.
• Block: Block ramp using braille values.
• Block2: Block ramp using a combination of color intensities & braille values.

Note: Unicode text is unaffected by the rendering style.

TUIView

UI view, built from a 2D array of TUICharacter.

• Two draw modes
  • Draw at prompt
  • Draw at origin
• Caching of rendered Ansi.
• Array of active characters to expedite draw, and to apply animation:
  • dissolve
  • materialize
• Painters Algorithm

TUIProgress

Flexible design allowing full customization using TUIBarBits:

• percent: % complete
• message: Status message
• elapsed: Elapsed time in seconds
• eta: Estimated total duration
• remaining: Estimate time remaining
• rate: Current rate of progression per second
• space: Space Character
• text: Custom text
• complete: Complete character / sequence
• incomplete: Incomplete character
• scanner: left to right activity scanner
• cylon: similar to Battlestar Galatica namesake
• animate: sequence animation
• spinner: sequence spinner

Ansi

Line Graphics

Extended Features

• Progress bar and Spinners
• Table views
• Charting: Bar, Stacker Bar, Line, Pie
• Gauges
• Menus
• Image view
• Sprites
• Run loop
• Support terminfo / termcap databases for terminal compatibilty

Ansi Control Sequences

The following xterm control sequence introducer (CSI) categories are supported:

1. Select Graphic Rendition
2. Cursor Control
3. Display Control
4. Line Control
5. Tab Control
6. Window Control
7. Private Mode: Set / Reset

Select Graphic Rendition

Character	Control Sequences
Attributes	Reset, Bold, Dim, Italic, Underline, Blink, Rapid Blink, Inverse, Positive Visible, Invisible, Crossed-Out, Double Underline.
Standard Colors	Black, Red, Green, Brown, Blue, Magenta, Cyan, Light Gray.
Bright Colors	Dark Gray, Light Red, Light Green, Yellow, Light Blue, Light Magenta, Light Cyan, White.
256 Colors	16 Base Colors + 216 Component Colors + 24 Grayscale.
RGB Colors	24-bit Colors — ISO-8613-3.

Cursor Control

Cursor	Control Sequences
Directional	Up, Down, Forward, Backward, Absolute Position (row, column)
Column	Absolute (move to specific column), Relative (offset from current column)
Row	Absolute (move to specific row), Relative (offset from current row)
Style	Blinking Block, Steady Block, Blinking Underline, Steady Underline, Blinking Bar, Steady Bar.
State	Save Cursor, Restore Cursor

Display Control

• Erase: Below, Above, All, Saved Lines (scroll back buffer).

Line Control

• Next, Previous, Insert, Delete.
• Erase: Cursor To Right, Cursor To Left, All.
• Scroll: Up, Down, Set Region.

Tab Control

• Forward, Backward
• Clear: Current Column, All

Window Control

• Move window to absolute x, y
• Resize window to absolute x, y
• Resize Text Area to absolute x, y
• De-inconify Window
• Raise to front of stack order
• Lower to bottom of stack order
• Refresh Window
• Restore Maximized Window
• Maximize Window
• Report: Position, Pixel Size, Character Text Area Size, Character Screen Size, Icon Label
• Change Icon Name and Window Title
• Change Icon Name
• Change Window Title

Private Mode Set / Reset

• Keyboard Action Mode
• Insert / Replace Mode
• Send / Receive Mode
• Linefeed Mode
• Cursors Keys Mode
• Designate Character Set
• Column Mode (80 / 132)
• Scroll Mode (Smooth / Jump)
• Video Mode (Reverse / Normal)
• Origin Mode
• Wrap Around Mode
• Auto Repeat Keys Mode
• Show Toolbar Mode
• Print Modes
• Cursor Mode (On / Off)
• Scrollbar Mode
• Font Shifting Function Mode
• Tektronic Mode
• Margin Bell Mode
• Reverse Wraparound Mode
• Logging Mode
• Screen Buffer Mode (Normal / Alternate)
• Keypad Modes
• Mouse Modes

Ansi Colors

The ANSI / VT100 terminals and terminal emulators are not just able to display black and white text, they can display colors and formatted text.

Terminal	8	16	256	RGB
aTerm	ok	~	-	-
Eterm	ok	~	ok	-
GNOME	ok	ok	ok	-
Guake	ok	ok	ok	-
Konsole	ok	ok	ok	-
Nautilus	ok	ok	ok	-
rxvt	ok	ok	-	-
Terminator	ok	ok	ok	-
Tilda	ok	ok	-	-
XFCE4	ok	ok	ok	-
XTerm	ok	ok	ok	-
xvt	-	-	-	-
Linux TTY	ok	~	-	-
VTE	ok	ok	ok	-
iTerm2	ok	ok	ok	-
iTerm3	ok	ok	ok	ok

Contributing

If you have comments, complaints and/or feature requests: open an issue or a pull request.

Author and license

African Swift

• github.com/AfricanSwift
• twitter.com/SwiftAfricanus

TKit is available under the MIT license. See the LICENSE file for more info.