Celeste Old Site for ZX Spectrum Next

Celeste Classic is an iconic platform game, originally developed by Maddy Thorson and Noel Berry, for the Pico-8 fantasy console (link).  They later developed Celeste, a highly acclaimed game that any platformer lover should play (link).

I already did a Spectrum Next port of Celeste Classic, an unofficial but faithful remake, for which I asked permission to Noel Berry and he kindly granted it.

During my research for the Pico-8 game, I came across this great mod by Amegpo. It incorporates some elements from the full Celeste game, such as tokens, dreamblocks and Badeline.

As I had already made the first remake, I thought it would be great to reuse most of the code for porting this mod, just changing maps and adding a few gameplay elements.

How to play

Help Madeline climb Celeste Mountain, through 30 screens of increasing difficulty. Jump, climb walls, dash into the void.

There are four directional controls (left-right-up-down) and two actions (jump and dash). You can redefine keys if the default map is not for you. A kempston joystick  connected to the joystick port 1 may be used (simultaneously with the keyboard). I like to use a Megadrive gamepad, so I have two action buttons available.

Jump into the air, Madeline will respond to directional buttons while airborne. If you push against a wall while falling by its side, fall speed will diminish. Also, you can jump from the wall, an even chain jumps. The dash is the most powerful movement, but it can be used only once until you touch floor. Don't forget to point the dash direction with the directional buttons, it will make a great difference!

Playing modes

The game has infinite lives and if you die, you restart the level. Keep passing levels and you will get to the end. 

If you reach the final level in less than one hour, the game will let you put your name in the hall of fame (which is saved, as the redefined keys).

It's a difficult game, but not impossible. With practice, it can be completed in a few minutes. During development, with all that testing, I have become quite good at it.

Installing

On a ZX Spectrum Next / N-Go / Xberry Pi, just copy the celeste.nex file to your SD card and run it from the browser. 

Game speed

Celeste for Pico-8 runs at 30 Fps.  Celeste for Next runs at 25 Fps at the standard Next mode (50Hz), so it's a bit slower (some will thank this). But the Next can be set to run at 60Hz (see manual), and the game will run as fast as in Pico-8.

If you want to try 60Hz running from emulator, use the scripts ending in "-60".

Development notes

I have tried to create a faithful port of the Pico-8 original. It's been a somewhat difficult task, because although the Pico-8 seems like low power console, it really isn't. It's a fantasy console which requires  some power to run (700MHz CPU and at least 512Mb RAM). Compared to the Next (28MHz Z80 with 2Mb RAM), it's a huge machine.

Pico-8 uses the Lua programming language, and internally uses 16.16  fixed point for numbers. I have been able to implement all gameplay and movement logic using 8.8 fixed point, using 16 bit integers on the Z80. At least, the graphic system of the Next (layer2, tiles, sprites) seems to get the work done.

Development tools used

• Godot Engine for prototyping the game before writing it for the Next.
• Aseprite for pixel art in tiles and sprites.
• Arkos Tracker 2 for creating chiptunes.
• Z88DK compiler.
• Python for resource format management.

Thanks & Mentions

• Marta, for her love and support during the development of the game.
• Maddy Thorson and Noel Berry for creating this wonderful game.
• Amegpo for creating a great mod backporting elements of the full Celeste game.
• Manuferhi for creating the N-Go clone, and his help in testing the game.
• Javi Ortiz El Spectrumero  for his support and diffusion of the game.
• Victor Iborra "EremusOne" for being someone to talk to about tech details.

System Requirements

Celeste Old Site for Spectrum Next has been developed and tested using:

• A N-Go (Spectrum Next clone by ManuFerHi) running Firmware v1.31 and Core v3.01.10, also tested with Firmware v1.44 and Core v3.02.00

The game should work on other versions / firmwares.