# Self-Voicing

Ren'Py supports a self-voicing mode in which a speech synthesizer is used to read out text and other interface elements. This is intended to make Ren'Py games accessible to the vision impaired.

The Self-voicing mode can be toggled by pressing the `v` key.

When in self-voicing mode, keyboard navigation is changed so that the up and down arrow keys with iterate through all focusable displayables on the screen.

When a displayable is focused, Ren'Py will read the text associated with that displayable out loud. If no displayable is focused, Ren'Py will read on-screen text that cannot be focused. This will generally include dialogue and other text that comprises the game.

## Speech Synthesis

Ren'Py relies on the operating system to provide speech synthesis services. To adjust the speed of speech synthesis and the voice used, adjust your platform's speech settings.

Windows
  On Windows, Ren'Py uses the Microsoft Speech API. Speech synthesis settings can be changed on the "Text to Speech" tab of the "Speech Recognition" control panel.
Mac OS X
  On Mac OS X, Ren'Py uses the `say` command. Speech synthesis settings can be changed on the "Text to Speech" tab of the "Dictation & Speech" control panel.
Linux
  On Linux, Ren'Py uses the `espeak` command. Espeak may need to be installed using your package manager before self-voicing mode will work.
Android, iOS, Chrome OS
  Self-voicing mode is not supported on Android, iOS, or Chrome OS.

The default voice can be selected on a per-platform basis, using the `config.tts_voice` variable. For example:

    init python:

        if renpy.windows:
            config.tts_voice = "Mark"
        elif renpy.macintosh:
            config.tts_voice = "Alex"
        elif renpy.linux:
            config.tts_voice = "english_rp"

The available voice vary based on the platform.

## Creator Concerns

Ren'Py's self-voicing works by extracting text from displayables and reading it to the player. Ren'Py extracts this text from two places.

Text displayables
  Ren'Py will extract text from a Text displayable, and make it available to be read to the player.
Alternative text

  Alternative text is supplied by a displayable's `alt` style property. It can also be supplied by actions supplied to buttons and values supplied to bars. Explicitly supplied alternative takes precedence over text supplied by actions or values, and both take precedence over text extracted from Text displayables.

  Alternative text is translated using Ren'Py's string translation mechanism. Alternative text takes precedence over text extracted from a displayable and its children, but such child text is made available as the "[text]" string substitution. No other string substitutions are allowed.

  Supplying the who_alt and what_alt parameters to Character sets the alt style property for the character name and body text, respectively. As an example, we define a Character that uses italics to indicate thoughts normally, but explicitly indicates thoughts via self voicing:

      define thought = Character(None, what_italic=True, what_alt="I think, [text]")

Descriptive Text

  Descriptive text is text that is displayed (and spoken) by the narrator if self-voicing is enabled. The text is not displayed if self-voicing is disabled. Self-voicing text uses the `sv` variable, which is defined to be similar to a character.

  `alt` = ...

    A character-like object that uses the narrator to speak text if self-voicing is enabled.

  For example:

      e "Hang on, this is gonna be a bumpy ride!"

      alt "And then the sun exploded..."

      # A complex and exciting cut scene.
      show event sun_exploding
      pause 10

  There is a variable that controls descriptive text:

  define `config.descriptive_text_character` = None

    If not None, this should be a character object that is used to display the descriptive text.

A self-voicing debug mode can be enabled by typing Shift+Alt+V. This will display the text that would be voiced on the screen for development purposes.