cuteflip

Python/Qt logic-port of the Voltorb Flip minigame from Pokémon HeartGold/SoulSilver's decompilation.

Quality Status: Gold Master

Functionality Status: MVP

License: GPL v3

Pokémon HeartGold/SoulSilver (HGSS) is widely regarded as one of if not the best in the mainline series. Full of content, one of the minigames is known as 'Voltorb Flip': it's essentially a Pokémon minesweeper clone with a few rule changes. Anyway, I really enjoyed this minigame and wanted to play it on my PC - but building a clone just isn't good enough. What I wanted was a fully logic-faithful PC port with the original board generation algorithms and levels. There's a decompilation of the HGSS ROM file happening on GitHub, and thanks to their efforts there is a C implementation (for the Nintendo DS) of Voltorb Flip we can look at.

The decomp is obviously very coupled to Nintendo DS hardware, so while the backend logic (board generation, scoring, randomness, levels) can be directly ported to Python, the graphics and UI had to be made from scratch. I decided on Qt. The rules of the game are:

• The game is a 5x5 grid, where a tile can be 1 coin, 2 coins, 3 coins or a voltorb (bomb),
• There are 8 levels, with the number of coins AND voltorbs increasing per level,
• A player needs to find all of the 2 and 3 coin tiles in a level to advance,
• If a player loses (clicks a voltorb) and HAS NOT flipped over a number of cards equal to their current level, they drop a level,
• The player has the number of coins AND the number of voltorbs in a column/row shown to them on screen.

There are a number of interesting characteristics of the NDS implementation we needed to port:

• Every level has 10 predefined configs containing the total number of voltorbs, coins and maximum voltorb-free tiles per row,
• Every level also has a distribution that describes how often those predefined configs are chosen,
• The randomness algorithm used is a 32-bit Mersenne Twister,
• The way the game places tiles on the board is a bit weird (sorry HGSS developers!)

• files/cuteflip-master-a641fc9-w.tar.gz

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