In September 2026, a developer detailed the progress made on z486_MiSTer, focusing on the emulation of 3D graphics cards, particularly the 3dfx Voodoo Graphics. The project, named zSST, implements the Voodoo Graphics features on an FPGA using a Xilinx KV260 board, allowing games like Tomb Raider to run with its original 3dfx renderer.
The zSST design incorporates key Voodoo features such as prepared triangles, texture filtering, mipmapping, depth and alpha tests, fog, blending, dithering, framebuffer access, and buffer swaps. The CPU and renderer operate at 100 MHz on the KV260, which has sufficient resources for this implementation, unlike the DE10-Nano board.
The Glide source code released by 3dfx in 1999 has been instrumental in understanding how to implement the graphics features. The Voodoo Graphics card processes triangles into pixels, relying on the host CPU for much of the 3D computation. The rendering pipeline is designed to handle multiple pixels simultaneously, achieving a peak output of 50 million pixels per second at a 50 MHz graphics clock.
The architecture of the Voodoo Graphics card is divided between two ASICs: the Frame Buffer Interface (FBI) and the texture mapping unit (TMU). The design allows for efficient memory access and processing, which is crucial for maintaining high throughput in rendering tasks. The zSST implementation aims to replicate this efficiency while adapting to the capabilities of the KV260 board.
The developer noted challenges in optimizing memory access patterns to ensure the pixel pipeline remains fed, as the FPGA accesses shared DDR memory. Caching techniques have been employed to minimize the number of memory accesses and reduce wait times for data retrieval. Overall, the project represents a significant effort in preserving and emulating classic graphics technology.