NEW TUTORIAL: Running OpenGL-based Games & Emulators on Adafruit PiTFT Displays
The Ideal: Adafruit’s PiTFT displays are razor sharp. Whereas small composite screens on the Raspberry Pi usually require some video scaling (resulting in blurriness), PiTFT uses the GPIO header, digitally controlled pixel-by-pixel for a rock steady image. Though not a lot of pixels, it works great for retro gaming (and the display neatly stacks above the board, no side protuberances for video cables).
The Downside: this GPIO link entirely bypasses the Pi’s video hardware, including the graphics accelerator. Many games and emulators rely on the GPU for performance gains. So the PiTFT has traditionally been limited to just a subset of specially-compiled emulators that can work and run well enough without the GPU.
The Solution: our latest PiTFT drivers, along with a tool called fbcp (framebuffer copy), careful system configuration, and (optionally) the much more potent Raspberry Pi 2 board open the doors to many more gaming options. Existing emulator packages (such as RetroPie, with dozens of high-performance emulators and ports) — previously off-limits to the PiTFT — can run quite effectively now!
The Plan
You’ll need:
- Any model of Raspberry Pi computer (Model A, B, A+, B+ or Pi 2).
- A 320×240 pixel PiTFT display (2.8″ resistive, 2.8″ capacitive, 2.2″ HAT). For gaming we won’t be using the touchscreen features, but still need to distinguish among the various models. The 3.5″ PiTFT (480×320) is not recommended for this project — more pixels means slower refresh.
- A 4GB or larger microSD card (or full-size SD for “classic” Model A or B).
- An HDMI monitor and USB keyboard are used temporarily during installation and setup.
Emulators require game ROM files. These are not included. RetroPie includes Pi-native ports of Doom, Duke Nukem 3D, Quake and Quake 3 that work without additional software.
Steps will include:
- Download and setup RetroPie using the temporary HDMI monitor.
- Download and setup additional Adafruit software “over” RetroPie.
- Configuration to redirect game output to the PiTFT screen; HDMI screen is no longer needed then.
Though we focus on RetroPie, some of these steps should be applicable to other software.