# 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. Self-voicing modes can be selected through the accessibility menu, which can be accessed by pressing `Shift+A`.

When in the `Shift+A` accessibility menu, the `R` key resets the self-voicing settings to the default values, then enables self-voicing. This can be used to reset the self-voicing settings if the user has changed them to a state that makes self-voicing unusable.

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 generally uses speech synthesizers provided by the operating system and web browser. Linux is the exception - the `espeak-ng` command must be installed for self-voicing to work on Linux.

The voice may be selected through the accessibility menu, which uses the `renpy.get_tts_voices()` function to list available voices and `Preference()` to set the voice. The precise list of available voices is platform and computer dependent.

On most platforms, 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.

## Other Modes

There are two other modes related to self-voicing.

Clipboard

  Clipboard mode can be toggled by pressing Shift+C. In clipboard mode, the text is copied to the clipboard instead of being played through TTS. This can be with screen readers or other assistive technologies that will present the clipboard contents to the user.

  It may also be useful for translation software that can read from the clipboard.

Debug

  Debug mode can be toggled by pressing Shift+Alt+V. In debug mode, the text that would be spoken is displayed on the screen, to help with development.

## 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 multiple 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 instances of the `Action` and `BarValue` classes. Explicitly supplied alternative text takes precedence over text supplied by Actions or BarValues, 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.

  For example:

      screen information(message, planet, badness):
          text message:
              color color_from_badness(badness)
              alt "Information for you : [text]. Badness is " + str(badness)

          text "ORIGIN_OF_MESSAGE_{color=#f00}[planet!u]{/color}":
              alt "Origin of message is " + planet

  In the above example, the `badness` and `planet` variables cannot be substituted directly using "[badness]". Concatenating it manually is a solution.

  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]")

  In screens, displayables may be given the `group_alt` property, which is used to give a group prefix that is spoken the first time a displayable with the same group prefix is focused, but will not be spoken again until a displayable with a different group prefix is focused.

  Displayables may also be given the `extra_alt` property, which is spoken when the '?' key is pressed while the displayable is focused. This is intended for more detail information about how a group of controls works.

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 `alt` 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, instead of the narrator.

The `config.tts_substitutions` variable can be used to substitute words in the text being spoken, to better control pronunciation. The voice can be selected through the accessibility menu (Shift+A), as can its speed. The voice is stored in `preferences.tts_voice`. Te speed of self-voicing is stored in `preferences.tts_speed`.

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.

## Python

The following functions are provided by the self-voicing system:

renpy.alt(s, translate=True, force=False)

  This queues s to be spoken. If translate is true, then the string will be translated before it is spoken. If force is true, then the string will be spoken even if self-voicing is disabled.

  This is intended for accessibility purposes, and should not be used for gameplay purposes.

renpy.get_tts_voices()

  Returns a list of available text-to-speech voice names. Returns an empty list if no voices are available, or if the platform does not support voice enumeration.