README
¶
Termbox
Termbox is a library that provides a minimalistic API which allows the programmer to write text-based user interfaces. The library is crossplatform and has both terminal-based implementations on *nix operating systems and a winapi console based implementation for windows operating systems. The basic idea is an abstraction of the greatest common subset of features available on all major terminals and other terminal-like APIs in a minimalistic fashion. Small API means it is easy to implement, test, maintain and learn it, that's what makes the termbox a distinct library in its area.
Installation
Install and update this go package with go get -u github.com/nsf/termbox-go
Examples
For examples of what can be done take a look at demos in the _demos directory. You can try them with go run: go run _demos/keyboard.go
There are also some interesting projects using termbox-go:
- godit is an emacsish lightweight text editor written using termbox.
- gomatrix connects to The Matrix and displays its data streams in your terminal.
- gotetris is an implementation of Tetris.
- sokoban-go is an implementation of sokoban game.
- hecate is a hex editor designed by Satan.
- httopd is top for httpd logs.
- mop is stock market tracker for hackers.
- termui is a terminal dashboard.
API reference
Documentation
¶
Overview ¶
termbox is a library for creating cross-platform text-based interfaces
Index ¶
- Variables
- func Clear(fg, bg Attribute) error
- func Close()
- func Flush() error
- func HideCursor()
- func Init() error
- func Interrupt()
- func SetCell(x, y int, ch rune, fg, bg Attribute)
- func SetCursor(x, y int)
- func Size() (int, int)
- func Sync() error
- type Attribute
- type Cell
- type Event
- type EventType
- type InputMode
- type Key
- type Modifier
- type OutputMode
Constants ¶
This section is empty.
Variables ¶
var (
IsInit bool = false
)
To know if termbox has been initialized or not
Functions ¶
func Close ¶
func Close()
Finalizes termbox library, should be called after successful initialization when termbox's functionality isn't required anymore.
func Init ¶
func Init() error
Initializes termbox library. This function should be called before any other functions. After successful initialization, the library must be finalized using 'Close' function.
Example usage:
err := termbox.Init()
if err != nil {
panic(err)
}
defer termbox.Close()
func Interrupt ¶
func Interrupt()
Interrupt an in-progress call to PollEvent by causing it to return EventInterrupt. Note that this function will block until the PollEvent function has successfully been interrupted.
func Size ¶
Returns the size of the internal back buffer (which is mostly the same as terminal's window size in characters). But it doesn't always match the size of the terminal window, after the terminal size has changed, the internal back buffer will get in sync only after Clear or Flush function calls.
Types ¶
type Attribute ¶
type Attribute uint16
const ( ColorDefault Attribute = iota ColorBlack ColorRed ColorGreen ColorYellow ColorBlue ColorMagenta ColorCyan ColorWhite )
Cell colors, you can combine a color with multiple attributes using bitwise OR ('|').
Cell attributes, it is possible to use multiple attributes by combining them using bitwise OR ('|'). Although, colors cannot be combined. But you can combine attributes and a single color.
It's worth mentioning that some platforms don't support certain attibutes. For example windows console doesn't support AttrUnderline. And on some terminals applying AttrBold to background may result in blinking text. Use them with caution and test your code on various terminals.
type Cell ¶
A cell, single conceptual entity on the screen. The screen is basically a 2d array of cells. 'Ch' is a unicode character, 'Fg' and 'Bg' are foreground and background attributes respectively.
func CellBuffer ¶
func CellBuffer() []Cell
Returns a slice into the termbox's back buffer. You can get its dimensions using 'Size' function. The slice remains valid as long as no 'Clear' or 'Flush' function calls were made after call to this function.
type Event ¶
type Event struct {
Type EventType // one of Event* constants
Mod Modifier // one of Mod* constants or 0
Key Key // one of Key* constants, invalid if 'Ch' is not 0
Ch rune // a unicode character
Width int // width of the screen
Height int // height of the screen
Err error // error in case if input failed
MouseX int // x coord of mouse
MouseY int // y coord of mouse
N int // number of bytes written when getting a raw event
}
This type represents a termbox event. The 'Mod', 'Key' and 'Ch' fields are valid if 'Type' is EventKey. The 'Width' and 'Height' fields are valid if 'Type' is EventResize. The 'Err' field is valid if 'Type' is EventError.
func ParseEvent ¶
After getting a raw event from PollRawEvent function call, you can parse it again into an ordinary one using termbox logic. That is parse an event as termbox would do it. Returned event in addition to usual Event struct fields sets N field to the amount of bytes used within 'data' slice. If the length of 'data' slice is zero or event cannot be parsed for some other reason, the function will return a special event type: EventNone.
IMPORTANT: EventNone may contain a non-zero N, which means you should skip these bytes, because termbox cannot recognize them.
NOTE: This API is experimental and may change in future.
func PollEvent ¶
func PollEvent() Event
Wait for an event and return it. This is a blocking function call.
func PollRawEvent ¶
Wait for an event and return it. This is a blocking function call. Instead of EventKey and EventMouse it returns EventRaw events. Raw event is written into `data` slice and Event's N field is set to the amount of bytes written. The minimum required length of the 'data' slice is 1. This requirement may vary on different platforms.
NOTE: This API is experimental and may change in future.
type InputMode ¶
type InputMode int
Input mode. See SetInputMode function.
func SetInputMode ¶
Sets termbox input mode. Termbox has two input modes:
1. Esc input mode. When ESC sequence is in the buffer and it doesn't match any known sequence. ESC means KeyEsc. This is the default input mode.
2. Alt input mode. When ESC sequence is in the buffer and it doesn't match any known sequence. ESC enables ModAlt modifier for the next keyboard event.
Both input modes can be OR'ed with Mouse mode. Setting Mouse mode bit up will enable mouse button click events.
If 'mode' is InputCurrent, returns the current input mode. See also Input* constants.
type Key ¶
type Key uint16
const ( KeyF1 Key = 0xFFFF - iota KeyF2 KeyF3 KeyF4 KeyF5 KeyF6 KeyF7 KeyF8 KeyF9 KeyF10 KeyF11 KeyF12 KeyInsert KeyDelete KeyHome KeyEnd KeyPgup KeyPgdn KeyArrowUp KeyArrowDown KeyArrowLeft KeyArrowRight MouseLeft MouseMiddle MouseRight )
Key constants, see Event.Key field.
const ( KeyCtrlTilde Key = 0x00 KeyCtrl2 Key = 0x00 KeyCtrlSpace Key = 0x00 KeyCtrlA Key = 0x01 KeyCtrlB Key = 0x02 KeyCtrlC Key = 0x03 KeyCtrlD Key = 0x04 KeyCtrlE Key = 0x05 KeyCtrlF Key = 0x06 KeyCtrlG Key = 0x07 KeyBackspace Key = 0x08 KeyCtrlH Key = 0x08 KeyTab Key = 0x09 KeyCtrlI Key = 0x09 KeyCtrlJ Key = 0x0A KeyCtrlK Key = 0x0B KeyCtrlL Key = 0x0C KeyEnter Key = 0x0D KeyCtrlM Key = 0x0D KeyCtrlN Key = 0x0E KeyCtrlO Key = 0x0F KeyCtrlP Key = 0x10 KeyCtrlQ Key = 0x11 KeyCtrlR Key = 0x12 KeyCtrlS Key = 0x13 KeyCtrlT Key = 0x14 KeyCtrlU Key = 0x15 KeyCtrlV Key = 0x16 KeyCtrlW Key = 0x17 KeyCtrlX Key = 0x18 KeyCtrlY Key = 0x19 KeyCtrlZ Key = 0x1A KeyEsc Key = 0x1B KeyCtrlLsqBracket Key = 0x1B KeyCtrl3 Key = 0x1B KeyCtrl4 Key = 0x1C KeyCtrlBackslash Key = 0x1C KeyCtrl5 Key = 0x1D KeyCtrlRsqBracket Key = 0x1D KeyCtrl6 Key = 0x1E KeyCtrl7 Key = 0x1F KeyCtrlSlash Key = 0x1F KeyCtrlUnderscore Key = 0x1F KeySpace Key = 0x20 KeyBackspace2 Key = 0x7F KeyCtrl8 Key = 0x7F )
type Modifier ¶
type Modifier uint8
const (
ModAlt Modifier = 0x01
)
Alt modifier constant, see Event.Mod field and SetInputMode function.
type OutputMode ¶
type OutputMode int
const ( OutputCurrent OutputMode = iota OutputNormal Output256 Output216 OutputGrayscale )
Output mode. See SetOutputMode function.
func SetOutputMode ¶
func SetOutputMode(mode OutputMode) OutputMode
Sets the termbox output mode. Termbox has four output options:
OutputNormal => [1..8] This mode provides 8 different colors: black, red, green, yellow, blue, magenta, cyan, white Shortcut: ColorBlack, ColorRed, ... Attributes: AttrBold, AttrUnderline, AttrReverse
Example usage: SetCell(x, y, '@', ColorBlack | AttrBold, ColorRed);
Output256 => [1..256] In this mode you can leverage the 256 terminal mode: 0x00 - 0x07: the 8 colors as in OutputNormal 0x08 - 0x0f: Color* | AttrBold 0x10 - 0xe7: 216 different colors 0xe8 - 0xff: 24 different shades of grey
Example usage: SetCell(x, y, '@', 184, 240); SetCell(x, y, '@', 0xb8, 0xf0);
- Output216 => [1..216] This mode supports the 3rd range of the 256 mode only. But you dont need to provide an offset.
- OutputGrayscale => [1..24] This mode supports the 4th range of the 256 mode only. But you dont need to provide an offset.
In all modes, 0 represents the default color.
`go run _demos/output.go` to see its impact on your terminal.
If 'mode' is OutputCurrent, it returns the current output mode.
Note that this may return a different OutputMode than the one requested, as the requested mode may not be available on the target platform.
Source Files