A low level utility library containing core definitions for the Glulx and Glk systems.
This extension is a low level utility library containing core defintions for the Glulx and Glk systems. This extension is released under the Creative Commons Attribution licence. Bug reports, feature requests or questions should be made at <https://github.com/i7/extensions/issues>. Chapter: Testing interpreter features (gestalts) We can test whether the player's interpreter supports various multimedia features using the following phrases: Table of interpreter functions the glulx version (a number) the version of the Glulx standard the interpreter implements the glk version (a number) the version of the Glk standard the interpreter implements the interpreter version (a number) the interpreter's own version number if glulx memory resizing is supported if glulx undo is supported if glulx memory copying is supported if glulx malloc is supported if glulx function acceleration is supported if glulx real numbers are supported if glk/glulx character input is supported if glk/glulx line input is supported if glk/glulx mouse input is supported whether any clicks at all can be detected if glk/glulx graphic-window mouse input is supported if glk/glulx text-grid mouse input is supported if glk/glulx timekeeping is supported whether the Glk timer can be set for one-off or periodic events if glk/glulx graphics are/is supported whether any graphics at all are supported if glk/glulx text-buffer graphics are/is supported if glk/glulx graphic-window graphics are/is supported if glk/glulx basic sounds are supported whether any sounds can be played if glk/glulx sound volume is supported whether the volume can be controlled if glk/glulx sound notification is supported whether an event will be raised when a sound finishes playing if glk/glulx hyperlinks are supported if glk/glulx hyperlink input is supported if glk/glulx mod sound is supported whether mod sounds can be played if glk/glulx PNG transparency is supported whether it is possible to layer PNG images with transparent alpha channels if glk/glulx unicode is supported if glk/glulx unicode normalization is supported if glk/glulx line input echo suppression is supported if glk/glulx line input terminators are supported if the glk/glulx system clock is supported whether the current time can be obtained if glk/glulx sounds are fully supported if glk/glulx resource streams are supported if glk/glulx graphics window character input is supported whether character input is supported in graphics windows You can test these at the start of play to warn the player if their interpreter does not support something your story uses. It is highly recommended that you also test them each time you use one of these features, because the player may have restored a savefile in a different interpreter, and what used to be supported may not be any longer.