The detail that got me: this runs on a board costing roughly six dollars, with 520KB of SRAM and no graphics hardware at all. Try Edge Tech's PicoVoxel engine ray casts an entire textured, animated voxel scene in software on the RP2350's two Cortex-M33 cores at 300MHz, and it still averages over 30 FPS.
The plumbing is where the craft shows. DDA ray casting is split across both cores, with the workload rebalanced every frame. Checkerboard raycasting and macrocell skips through empty space keep the tracing focused, and finished frames go out to the display over DMA. The image is traced at 160x120 and then enlarged to 320x240 with edge-preserving depth filtering. Output lands on a 320x240 ST7789 LCD connected with jumper wires, a DualShock 4 handles input over a micro-USB OTG host link, and audio leaves the pins as PWM into an active speaker.
Plenty stands out in the result. The world fits inside a 64x64x32 volume yet holds a handcrafted Japanese countryside with mountains, sea, flowing water, a tunnel, a shrine, a lighthouse. Seventeen block varieties carry attributes like texture, transparency, animation and cutout, the camera can enter translucent water with underwater rendering effects, foliage cutouts let background geometry peek through between leaf pixels, and fog and shadows render too. Seven nature sounds play, with volume scaling by proximity to their origins. Circle toggles Play and Edit Mode, and in Edit Mode L1 and R1 cycle the inventory while square places and triangle removes blocks.
It is a tech demo rather than a finished game, and the maker names the core problem plainly: fitting the renderer, framebuffer and world data into 520KB while keeping it responsive. A future technical walkthrough of the rendering pipeline and SRAM optimization is planned. The code is MIT licensed on GitHub, with pre-built UF2 firmware on the releases page.
Project by Try Edge Tech. Watch it on their YouTube channel: