Crystal Caves came out in October 1991, Apogee's first game with smooth scrolling EGA graphics. Episode One, Troubles with Twibbles, was the shareware episode; Episodes Two and Three were sold by mail.
Everything you see and hear comes from the Episode One shareware files:
· The levels live inside CC1.EXE, which is packed with LZEXE. Unpacked, the 19 maps (16 caves, the main level, the intro and the finale) are rows of 40 characters, one character per tile, stored as Pascal strings. The number of rows per map is written into the program code, not the data.
· The graphics are in CC1.GFX: 1,150 tiles of 16×16 pixels in 23 chunks, each pixel stored as four EGA colour planes plus a transparency mask. The font and the window frames are three small files in the same format.
· The sounds are the 36 PC-speaker effects in CC1-1.SND to CC1-3.SND, lists of frequencies played as a square wave.
· The pictures (the Apogee logo, the title, the credits and the ending) are 16-colour PCX files.
· The words (the story, the instructions, Mylo's ship's log and the messages) are also in the program.
The game rules come from OpenCrystalCaves, an open-source remake of Episode One by Simon Sandström, congusbongus and others. It worked out what each map character means and how each creature moves. Its C++ was translated to JavaScript, keeping the original's look where the remake had changed it on purpose: the dark caves use the EGA palette, there are no added signs, and the original's one-time messages ("Use the fire key to activate a lever") are back.
One game tick is four frames of the 70 Hz EGA display, 17.5 ticks a second, as in the original.
· The physics and creature behaviour are OpenCrystalCaves' reconstruction from watching the game. They are close, but not taken from the program code.
· High scores aren't kept.
· You can restart a cave from the menu. In the original you had to quit to the main level and walk back in.
· Saved games are kept in this browser: ten slots, plus an automatic save each time you're back on the main level.
Crystal Caves ©1991 Apogee Software. Frank Maddin: programming, graphics, game design. George Broussard: graphics, game design. Peder Jungck: graphics routines. Lucinda Maddin: graphics. Scott Miller: game design. Jim Norwood: full screen artwork.
OpenCrystalCaves ©2017 Simon Sandström and contributors, MIT licence:
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.