Sets the termbox output mode. Termbox has four output options:

1. 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);

2. Output256 => [1..256]

In this mode you can leverage the 256 terminal mode:
0x01 - 0x08: the 8 colors as in OutputNormal
0x09 - 0x10: Color* | AttrBold
0x11 - 0xe8: 216 different colors
0xe9 - 0x1ff: 24 different shades of grey

Example usage:
    SetCell(x, y, '@', 184, 240);
    SetCell(x, y, '@', 0xb8, 0xf0);

3. Output216 => [1..216]

This mode supports the 3rd range of the 256 mode only.
But you dont need to provide an offset.

4. OutputGrayscale => [1..26]

This mode supports the 4th range of the 256 mode
and black and white colors from 3th range of the 256 mode
But you dont need to provide an offset.

In all modes, 0x00 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.

SetOutputMode is referenced in 0 repositories