OpenPeteDownloadA native PC port of Spyro the Dragon. Named after Spyro's name during original development. A high performance static recomp with a custom renderer to optionally fix all the original's visual artifacts.
OpenPete needs your own copy of the original NTSC-U disc (SCUS-94228). No game data is distributed. The build is unsigned, so Windows will warn the first time you run it—see known issues, and the FAQ for the checksum to verify the download against.
The retail executable is statically recompiled into C. Its PSX library calls are handled by a custom runtime backed by PsyCross. The recompiled code can be surgically replaced with hand-decompiled C.
The renderer reads directly from game state rather than from a stream of PSX GPU commands, so it knows what a polygon is and not just where it landed, allowing full control over presentation. This allows rendering with true depth, high frame rate, arbitrary aspect ratio, high resolution while completely eliminating PSX wobble and warped textures.
Drag the divider to wipe between the original PlayStation output and OpenPete. Pick a frame rate and aspect ratio, and toggle enhancements, to change what the right-hand side is running.
Rendering is decoupled from simulation. The game still ticks at 29.913 Hz exactly as it did on hardware; presentation runs at any framerate your PC can support with movement, transforms, animation and scrolling textures interpolated sub-tick.
Hor+ widescreen (16:9, 21:9, 32:9, etc. or follow-the-window). Extending the aspect ratio does not affect gameplay such as enemy behavior.
Drop replacement PNGs of any resolution into a folder and they display in place of the originals: world, mobys, HUD and the title logo alike.
The low-poly and low-resolution LOD tiers can be pushed far back or switched off entirely so distant terrain keeps its detail instead of snapping in.
By default, vertices keep their full precision, textures are sampled with true perspective correction and colour is full 24-bit. Toggles recreate the console's vertex snapping, affine texture mapping and 15-bit dithered colour, for when you want the hardware's exact look.
Geometry is depth-tested rather than sorted through the PlayStation's ordering table, so the sorting artifacts inherent to a painter's algorithm don't occur.
Snapshot and restore anywhere, step frame by frame, rewind, or run ahead of the simulation to cancel out input latency.
Source-first mods, C and shaders both, compiled when the game starts, with no toolchain to install. They can override game functions, add per-object shaders, and interact with the runtime itself.
Any of the 48 music tracks can be replaced with a WAV file. The game still drives looping and the long-idle track rotation, so overrides behave like the originals.
A pause-menu-styled overlay, drawn with the game's own gold glyph text, changes aspect, frame rate, supersampling, LOD, textures and wobble live.
Windows 10/11 (64-bit)
Nothing in the build demands a particular Windows version; the limiting factor is Vulkan 1.2 driver support.
Any x86-64 CPU
Any 64-bit Intel or AMD chip. Roughly anything from the last 15 years should be fine.
A GPU with Vulkan 1.2 support
Roughly a GeForce GTX 600, Radeon HD 7000 or Intel HD 500-series and newer, on a current driver. There is no Direct3D or OpenGL fallback. Around 2 GB of VRAM at 1080p with SSAA ×4.
8 GB recommended, 4 GB workable
Playing takes about 300 MB.
~1.2 GB once first run finishes
The download unpacks to ~450 MB, most of it the bundled compiler. First run then copies your disc image into library/ (~640 MB) and writes the code it compiles from it alongside (~90 MB).
Graphics
The PSX OT rendering covers up issues in the original game's geometry that are exposed by rendering with a true depth buffer.
Graphics
Various visual artifacts remain, including:
Graphics
Rendering cutscenes at widescreen aspect ratios reveal missing geometry or mispositioned mobys.
Graphics
Using extended level-of-detail, the fog scale is not being correctly applied (e.g. in Beast Makers).
Platform
Until code signing is in place, SmartScreen will warn on first run or antivirus may report false positives. The build is safe, but you may need to override any warnings.
Audio
Audio is the wrong volume for certain sounds, and the current stereo mixing solution can result in a tinny echo.
Audio
When holding Tab to fast-forward, the audio is not sped up and can fall out of sync with the simulation.
Platform
Dragging or resizing the window pauses gameplay.
FAQ
Yes. OpenPete ships no game data at all: no levels, textures, audio or code from the disc. You supply an original NTSC-U Spyro the Dragon disc image (SCUS-94228), which is verified by checksum before anything runs. Only a .bin/.cue disc image with the sha1 hash 1e08ae8df01acf7ee5d9cb6931b5f8c1bc905fcb or sha256 hash 95f03abf97c9ff0b2a64888ed7dbbb4b59a7b4363cf188cd0a562b95cfd4809f is supported right now.
No. The game's machine code is translated to C ahead of time and compiled for your CPU, and a runtime handles the console's system calls. No hardware is simulated and no BIOS is involved.
NTSC-U SCUS-94228 only. Other regions and revisions have different code layouts, and the port's function addresses and overlay maps are specific to this one. Support for other releases is possible but not planned.
No. Widescreen, frame rate, draw distance and texture replacement only change the presentation. They never write to the game's memory or to anything the game can read back. Regression tests compares simulation output against emulation traces to catch any leaks.
Yes. Saves are written to an ordinary .mcr memory card image on your disk, the same format emulators use, so you can bring a card across in either direction.
Game:
OpenPete:
No plans yet. The runtime is deliberately game-agnostic: it holds no Spyro-specific addresses, and per-game details sit behind a narrow interface.
There's still a lot of work to perfect Spyro 1.
Soon™. Mods are written as C source and shaders, compiled when the game boots, with no development toolchain to install. They can override game functions, add post-processing effects (like CRT filters), apply shaders to specific objects (e.g. Spyro, terrain), replace textures and swap music.
The modding SDK does not ship with this release: the API is still in heavy flux and is being stabilized.
The simulation is pinned to the console's 29.913 Hz tick and never runs faster. Extra frames are generated by interpolating transforms, animation, camera and texture scroll between two simulated ticks, so motion is smooth while physics, timing and behavior stay exactly as authored.
This does have the side effect of adding 1 sim-tick of input latency.
Not recommended yet. Times from OpenPete are not comparable to console or emulator runs, and no leaderboard recognizes it as a platform.
The simulation is meant to advance at a fixed 29.913 Hz, but runtime and renderer work can still stall a tick: a slow present blocks the simulation thread, so the frames can drift from wall-time making it inaccurate.
Input is currently delegated to PsyCross and needs reworking to be made more consistent and precise.
Level load times need to be slowed down a bit and made consistent in a speedrun mode to account for slower hardware.
Save states, rewind, runahead, and non-whitelisted mods (e.g. simple skins) would need locking out for a speedrun mode.
Integration with LiveSplit for automatic and accurate timing.
But sure, you can speedrun it for funzies!
Windows on x86-64 is what is published today. A Linux AppImage is being tested now! macOS on Apple Silicon is planned but has no build yet.
The Windows zip for v0.1.4 has the SHA-256 hash 7ba215834c6a1e23d0642b6c749c6335853a18cc566805c0a39bcf2cd5ab1359. In PowerShell, Get-FileHash openpete-v0.1.4.zip prints the same value if the file arrived intact.
OpenPete is based on a matching decompilation of Spyro the Dragon: an effort to rewrite the game in C such that the same compiler reproduces the retail executable byte for byte. If the bytes match, the C is what the game does.
Matching every function takes years, so the port doesn't wait on it. Static recompilation covers whatever hasn't been decompiled yet, and matched functions replace it as they land.
Developed by @tyscorp
Special thanks to @altro50, for his continued work on reverse engineering and decompilation of Spyro 1.