Snake Game

Snake Game is a faithful recreation of the timeless mobile classic, built natively for the CASIO ClassPad II using the Hollyhock-3 SDK. Guide your growing serpent across a grid-based playfield, consume fruit to extend your length, and avoid collisions with walls or your own tail. Simple to learn, challenging to master.

Features

• Classic grid-based gameplay: move in four directions, grow with each fruit consumed
• Responsive arrow key controls: intuitive input with direction locking to prevent accidental reversals
• Real-time score tracking: display updates as your snake lengthens
• Efficient rendering: optimized draw loop using direct VRAM access for smooth visual updates
• LFSR-based fruit spawning: deterministic pseudo-random placement that avoids snake occupancy
• Lightweight footprint: minimal memory and CPU usage for reliable performance on calculator hardware

Controls

Direction changes are queued safely: attempting to reverse direction (e.g., North to South) is ignored to prevent immediate self-collision.

Technical Notes

• Grid resolution dynamically adapts to screen dimensions using a 20-pixel block size
• Snake state is stored in circular buffers with a maximum length of 50 segments
• Fruit placement uses a 32-bit LFSR with polynomial x^32 + x^22 + x^2 + x for reproducible randomness
• Color scheme uses RGB565 encoding: black background, red snake, green fruit
• Score display reserves the top 24 pixels of the screen for real-time feedback

Requirements

• CASIO ClassPad II (fx-CP400 or compatible)
• Hollyhock-3 custom firmware
• Approximately 500 KB free storage space

Development History

Originally implemented by The6P4C for early Hollyhock environments, this version was refined by SnailMath for compatibility with Hollyhock-3. The codebase prioritizes clarity and portability, serving as both a playable game and a reference example for input handling, graphics rendering, and game loop design on the ClassPad platform.

Tips for High Scores

• Plan turns early to avoid boxing yourself in as the snake grows
• Use the edges of the playfield to create safe turning corridors
• Monitor the score display to anticipate when the snake approaches maximum length
• Practice consistent rhythm: rapid directional changes increase collision risk

Troubleshooting

If the game does not launch, verify that the .hh3 file is placed in the calculator root directory and that Hollyhock-3 is properly installed. If input feels delayed, ensure no other background applications are consuming CPU cycles. The game exits cleanly via POWER or CLEAR; if the system becomes unresponsive, a battery removal will reset the device without affecting stored data.