TCG - terminal cell graphics

Go Graphics library for use in a text terminal. Only 1bit graphics can be used with two colors. Used unicode block symbols for drawing. 2x3 mode is supported by the Iosevka font or some terminals (like default on Ubuntu).

Features

• Available 5 graphics modes, from 2x3 pixels grid for terminal symbol to 1x1, 1x2 and 2x2, or you can create own custom mode with your graphics
• Set/get one pixel
• Drawings: lines (vertical, horizontal, or with any angle), boxes, circles, arcs
• Fill area with a different options, for example fill with patterns
• Buffer manipulating: cut, clone, convert to/from stdlib Image or text
• Buffer transform: BitBlt with options, clear, flip, invert, scroll (vertical, horizontal)
• Sub-package for turtle graphics, also available drawing by text script
• Sprite support with Put, Withdraw, Move, etc methods

Install

go get github.com/msoap/tcg

Usage

package main

import (
	"log"
	"time"

	"github.com/gdamore/tcell/v2"
	"github.com/msoap/tcg"
)

func main() {
	tg, err := tcg.New(tcg.Mode2x3) // each terminal symbol contains a 2x3 pixels grid, also you can use 1x1, 1x2, and 2x2 modes
	if err != nil {
		log.Fatalf("create tcg: %s", err)
	}

	i := 0
	for {
		pixColor := tg.Buf.At(10, 10)      // get color of pixel
		tg.Buf.Set(11, 11, pixColor)       // draw one pixel with color from 10,10
		tg.Buf.Line(0, 0, i, i, tcg.Black) // draw a diagonal line
		tg.Show()                          // synchronize buffer with screen

		if tg.TCellScreen.HasPendingEvent() {
			if ev, ok := tg.TCellScreen.PollEvent().(*tcell.EventKey); ok && ev.Rune() == 'q' {
				break // exit by 'q' key
			}
		}
		i++
		time.Sleep(time.Second)
	}

	tg.Finish() // finish application and restore screen
}

See more examples in examples folder.

Screenshot

Game of Life example in iTerm2 terminal:

See more screenshots.

TODO

• fonts support
• sprites
• animation in sprite

See also

• Go terminal library - github.com/gdamore/tcell
• Turtle graphics
• Try it in the Go Playground

Unicode symbols:

• Block Elements - wikipedia
• Block Elements - unicode.org
• Symbols for Legacy Computing - wikipedia
• Symbols for Legacy Computing - unicode.org

Supported fonts (for "2x3" mode):

• Iosevka font