stella2023/stella/Changes.txt

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                               Release History
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1.2 to 1.3: (February 17, 2003)

  * Improved TIA sound system so that games with digitized audio work

  * Added saving and loading of game state to the core; X11, SDL, and DOS
    versions current support saving and loading game state

  * Added support for F4 bankswitching method

  * Pitfall II DPC sound emulation completed

  * Fixed a bug which caused the difficulty switches to operate backwards

  * Changed DPC auto-detection to use file size so that Pitfall II mods work

  * Modified RIOT timer emulation so that startup values are random

  * Added 3F bankswitching auto-detection routine so that homebrews and
    demos work without a stella.pro entry

  * Updated the TIA message boxes so they look a little nicer 

  * Latest stella.pro file included in distribution

  * Added some developer options to the core, and the ability to change game
    width, height, xstart, ystart, and others while the emulation is running.
    Added ability to switch between NTSC and PAL at runtime, and the ability
    to save the current properties to a file or to merge the changes into the
    stella.pro file; X11 and SDL versions supported for now (compile option)

  * External sound server for the X11 and SDL versions no longer required, as
    all sound code is now integrated into the core 

  * Changed locations of the user's config files for the X11 and SDL versions;
    the user's stellarc file is now located in $HOME/.stella/stellarc, state
    files are located in $HOME/.stella/state/ and the stella.pro file is
    located in $HOME/.stella/stella.pro

  * Changed the way options are supplied on the commandline for the X11 and
    SDL versions. Now all commandline options take exactly the same arguments
    as in the INI file.

  * Added "-accurate" command line option to choose between accurate
    (CPU-intensive) timing or less accurate (CPU-friendly) timing to X11
    and SDL versions. This is the final version of what was considered
    experimental timing code in Stella 1.2.

  * Added "-sound" command line option to choose which sound backend to
    use (alsa, oss, sdl) with the X11 and SDL versions.

  * Added the developer command line options to the X11 and SDL versions,
    which are only activated in developer builds: -Dformat, -Dwidth,
    -Dheight, -Dxstart, -Dystart, -Dmerge 

  * Fixed window resize bug in the X11 port

  * Added "-nosound" command line option to the DOS port to disable audio

  * DOS port supports a "-vsync" option to synchronize emulation with the
    video blank of the video card

  * Changed VGA code in the DOS port to use a 60Hz 320x200 and a 60Hz
    320x240 graphics mode

  * DOS port has been updated to run better under Windows NT, 2000, and XP.
    There are still issues with the sound, however, it is usable.

  * DOS port is using a new Sound Blaster driver created by Matt Conte which
    supports auto-detection of sound cards.

  * DOS port supports a STELLA_HOME environment variable that defines 
    the location of config files.
 
  * In the DOS port the stella.pro file is searched for first in the
    current working director and then in the $STELLA_HOME directory

  * In the DOS port the ROM image is searched for first using the
    specified path, then in $STELLA_HOME/ROMS, and finally in $STELLA_HOME
  
Cyberstella 1.2.1 (May 16, 2002)

  * Removed the built-in games until some legal stuff is sorted out

Cyberstella 1.2 (May 10, 2002)

  * Initial release of a new WIN 32 port of Stella

DOS 1.2 to DOS 1.2.1: (April 28, 2002)

  * Fixed a bug with control keys being confused with the pause key

  * Fixed a bug with the pause key causing the application to lockup

1.1 to 1.2: (April 21, 2002)

  * Improved illegal CPU instruction support. Thrust and Qb will now operate
    correctly.

  * Improved emulation of undefined TIA reads. The ball in Video Pinball
    finally bounces off of the paddles!

  * More accurate NTSC and PAL palettes. These palettes should be much more
    like the colors displayed on a real TV.

  * PAL color loss is now emulated. If a PAL game displays an odd number
    of scanlines then the next frame will be displayed in black & white.

  * TIA emulation improved to fix some problems with Pole Position,
    Fatal Run, Dolphin, Decathlon, Robot Tank, and Hole Hunter.

  * Support for Pitfall II has been added, however, the enhanced sound
    provided by the DPC chip found in the Pitfall II cartridge isn't
    currently emulated.

  * Support added for the Commavid (CV) bankswitching method.

  * Support added for the Megaboy cartridge.

  * Improved Supercharger emulation including a new BIOS that shows the
    vertical blue progress bars like the real thing.

  * Code for the emulation core has been updated to work with newer C++
    compilers compliant with the C++ standard.

  * Basic message support added to the TIA emulation. This allows a short
    message to overlay the TIA frame. Currently, it's used when switching
    color modes and difficulty settings.
 
  * The internal data structure for the stella.pro file was changed from
    a resizable array to a binary search tree. This results in quicker
    startup times.

  * An SDL port of Stella is available (requires SDL 1.2.0 or greater)

  * Added option to not load in the whole stella.pro file when starting 
    Stella. This option is enabled on the X11, SDL, and DOS versions. Win32 
    version is left alone since it's needed for loading multiple games from 
    the UI. Saves on memory usage.

  * Added INI file option to the X11 and SDL versions. Options can be 
    specified in this file instead of entering them on the commandline. Any 
    options entered on the commandline override options in the INI file.  
    File is called stellarc. For the X11 and SDL versions, it can be in
    either $HOME (as $HOME/.stellarc) or in /etc (as /etc/stellarc).  The
    one in $HOME has higher priority than the one in /etc.

  * Added snapshot support to the X11 and SDL versions. Pressing F12 saves 
    the current screen in PNG format. Requires PNG library.

  * Removed stella.pro file from the binary, resulting in large space
    savings. The stella.pro file is no longer optional.  For the X11 and
    SDL versions, it can be in either $HOME (as $HOME/.stella.pro) or in
    /etc (as /etc/stella.pro). The one in $HOME has higher priority than
    the one in /etc. For DOS and Win32 versions, the stella.pro file must
    be in the same directory as the executable.

  * Added pause functionality to the core. Implemented in DOS, X11, and
    SDL versions for now.

1.0 to 1.1: (February 26, 1999)

  * DOS and Linux versions support real Atari 2600 paddles using a 
    special PC game port adaptor

  * Linux version uses the new 1.2.x joystick driver API

  * Added support for the "-display" option to the X Window version

  * Added support for private colormaps to the X Window version

  * Fixed a few bugs in the Supercharger emulation

    - A major bug in the ROM loading routine was fixed

    - Multi-loading in "Escape from the Mindmaster" works correctly

    - All Supercharger games load and execute at this point

  * Added a small hack to the TIA code to fix a display problem in "Escape 
    from the Mindmaster"

  * Improved TIA emulation to support the RESPx multi-sprite trick

1.0b1 to 1.0: (October 7, 1998)

  * DOS version supports 320x200 and 320x240 graphics modes

  * Several portability issues have been resolved 

  * Preliminary support for Chris Wilkson's Megacart bank-switching scheme

  * BSDI target included in makefile 

  * Improved Users Manual in several "popular" formats

0.7 to 1.0b1: (July 25, 1998)

  * Supports the following controllers:

      Joysticks, Paddles, Booster-Grip, Keyboard and Driving

  * Supports the following bank switching methods:

      2K, 3F, 4K, AR, E0, E7, F4SC, F6, F8, F8SC, FASC, FE

  * Properties are associated with games using their MD5 checksum
    calculated on the entire ROM image

  * Uses the new 'stella.pro' file format for game properties

  * Includes Erik's latest stella.pro properties file

  * New frame rate throttle code for X windows GUI

  * Based on the new and improved M6502 CPU emulation

  * Improvements to TIA emulation

    - Support HMOVE blanks

    - Improved Cosmic Ark star field effect

    - Some support for the RESPx multiple sprite trick

    - Support NTSC and PAL palettes

  * Improvements to PIA emulation (timing)

  * Improved Supercharger emulation

0.6 to 0.7: (June 7, 1997)

  * Improved emulation speed of TIA and 6507

  * Added Starpath Supercharger support

  * Added Tigervision bank-switching support (3F bank-switching)

  * Added pause game feature for Unix and DOS

  * VCS files combined into a single builtin property file

  * Added TIA HMOVE "feature" to support Cosmic Ark stars

  * Improved TIA VSYNC code so that it works more like the real
    thing (0.6 VSYNC code caused the graphics of some games to
    be off such as Alien and Battle Zone)

  * Added two 6507 emulators: one is designed to act more like
    the real thing, while the other is designed to be as fast as
    possible (required for Supercharger support)

  * Changed TIA peeking so lower nibble of byte read is the same
    as the TIA address being accessed (Warlords now works)
  
0.5 to 0.6: (January 18, 1997)

  * Fixed collision detection problem (Freeway works)

  * Changed PIA timing code to fix screen jitters

  * Added new bank-switching methods: F4SC (Fatal Run), E7 (Burgertime)

  * Fixed some code in the TIA emulation that caused SEGFAULTS

  * Improved frame rate throttling code to work better on fast machines

  * Improved TIA emulation (missle graphics are fully emulated now)

  * Included Bob Colbert's "Okie Dokie" game

  * Uses version 1.1 of the TIA Sound library by Ron Fries

0.4 to 0.5: (November 17, 1996)

  * Added sound support

  * Added new bank-switching methods: F8SC (Defender II), FASC (CBS RAM+)

  * Changed TIA so peeking $E and $F return $F not $0 for Haunted House

  * Changed PIA timing code to fix screen jitters in Frogger

  * Addressing scheme rewritten

  * Optimized 6507 memory accesses

  * Randomized memory in PIA upon startup

  * Removed auto-disabling of objects at the start of a frame
    so you can't walk through walls in Adventure

  * Changed the X windows terminal update method to make it faster and
    easier to understand

0.3 to 0.4 (August 28, 1996):

  * TIA code has been optimized some

  * Some games can be played with just a ROM image

  * New search method for ROM images (no more STELLA_PATH)

  * Delta screen update supported

  * Better error handling added to the "core"

0.2 to 0.3 (July 12, 1996):

  * Keyboard joystick support is much better (Daniel Marks)

  * Paddles are now supported via the mouse (Bradford Mott)

  * Many portability issues have been resolved (Keith Wilkins)

  * Fixed a problem with the 6507 ADC and SBC instructions that caused
    some games (Enduro) not to work correctly (Bradford Mott)

  * Power Macintosh port (Aaron Giles)

  * Windows 95 & NT port (Jeff Miller)