ZVision

Z-engine
Engine developer	RichieSams
Companies that used it	Activision
Games that use it	Zork Nemesis, Zork: Grand Inquisitor
Date added to ScummVM
First release containing it	N/A

The Z-engine was the engine used by Activision in Zork Nemesis and Zork: Grand Inquisitor.

This engine is being added by the GSoC student RichieSams to ScummVM as part of the GSoC 2013.

The ScummVM engine uses Marisa Chan's Z-engine re-implementation, which is available from http://github.com/Marisa-Chan/Zengine, as a reference.

It should be noted that from a technical viewpoint, this engine has nothing in common with the MADE engine used for Return to Zork. It should also not be confused with the Z-machine which is the original Virtual Machine used for the original Zork text adventure games.

Immediate TODO's

• Finish InputControl implementation
• Implement SaveControl
• Test the SaveManager against gjse.scr (save room) and gjre.scr (restore room)
• Add a dirty rectangling system for RenderManager AlphaEntries so we're not rendering them to the backbuffer every frame

List of TODO's for Z-Engine to be playable

• Fix audio problems in videos
  • This is a problem with Video::VideoDecoder
  • Essentially, Zork videos require the sound chunks to be read as one continuous stream
  • The current model puts each chunk into a separate AudioStream and then queues the streams
  • This is being worked on by clone2727
• Finish implementing the rest of the ResultActions. (See actions.h)
  • ActionDebug
  • ActionDisableVenus
  • ActionDisplayMessage
  • ActionDissolve
  • ActionDistort
  • ActionFlushMouseEvents
  • ActionInventory
  • ActionKill
  • ActionEnableMenuBar
  • ActionPanTrack
  • ActionPreferences
  • ActionRegion
  • ActionRestoreGame
  • ActionRotateTo
  • ActionSaveGame
  • ActionSetVenus
  • ActionStop
  • ActionSyncSound
  • ActionTTYText
  • ActionUniverseMusic
• Finish implementing the rest of the Controls
  • InputControl
  • SaveControl
  • SlotControl
  • SafeControl
  • FistControl
  • HotMovieControl
  • PaintControl
  • TilterControl
• Implement inventory support
• Implement the menu
• Implement subtitles
• Implement saving preferences
  • Scroll speed
  • etc.

ZGI specific TODO's

• Determine why gary.scr doesn't load properly
  • This is the first "room". It loads up the environment variables, the opening movie, and then the main menu
• Implement spellbook support

Other TODO's

• Make sure all image rendering is endian safe
• Look into NOT flatting all the files to root
  • This would require keeping track of what room you're in so that you can use the correct parent folder
  • Look at NEMESIS.ZIX and INQUIS.ZIX
• Re-order the if-then statements in scr ResultAction parsing to use the order of highest occurance (See scr_file_handling.cpp: Line 150
• Evaluate all in-engine warnings/debug messages and perhaps move them to higher debug channels (Or ZEngine specific debug channels)
• Clean out unused member functions from the Console class (See console.h)
• Convert pointer initializers to nullptr instead of 0
• Add 'true' UTF-16 support for non-english versions of the game. (See StringManager)

Current Progress

• Current WIP for Z-engine, on a git fork from ScummVM