Nearly three decades later, The Legend of Zelda: Ocarina of Time still has a few tricks hiding behind the curtain.
While Nintendo’s 1998 classic was famous for bringing Zelda into 3D, not every location in Hyrule was actually rendered as a fully three-dimensional environment. Some of the game’s most familiar interiors and sections of Hyrule Castle Town relied on pre-rendered images and carefully placed fixed cameras to create the illusion of detailed 3D spaces.
Modder and 3D artist Reonu has spent more than a year taking those old backdrops apart and rebuilding them as places Link can actually walk around and view from any angle.
The work-in-progress project has the fitting provisional name OoT unJPEG, and the goal is ambitious: replace all of Ocarina of Time’s pre-rendered environments with real-time 3D geometry while keeping them faithful to the visual style of the original Nintendo 64 game.
Hyrule Castle Town Looks Surprisingly Different With a Free Camera
Reonu’s first public demonstration focuses on Hyrule Castle Town, and it immediately shows why this project is more interesting than a simple graphical upgrade.
In the original game, areas such as the Market use a fixed viewpoint. Link moves around in front of a detailed pre-rendered scene, but players can never rotate the camera to see what exists outside the intended frame.
OoT unJPEG replaces those images with actual models.
That means the camera can finally move behind Link as it would throughout much of the rest of Ocarina of Time. Players can also use the first-person view to look around locations that were never designed to be seen from those angles. Reonu has even preserved the original fixed-camera presentation, allowing players to switch back and forth and see how closely the new geometry matches the old backgrounds.
It produces a strange effect if you know the N64 version well. Castle Town still looks like Ocarina of Time, but suddenly there are corners, walls and pieces of architecture where our brains have spent the last 28 years accepting a flat image.
And Reonu isn’t trying to make these environments look like Ocarina of Time 3D.
The stated goal is specifically to recreate them as though Nintendo had built the locations using Nintendo 64-era 3D graphics in the first place.
Castle Town Is Now One Continuous Area
Rebuilding the scenery in 3D has also allowed Reonu to change something players will notice immediately: the loading transitions around Castle Town.
In the original Ocarina of Time, moving between the town entrance, Market, back alleys and the area outside the Temple of Time involves separate scenes and transitions.
For OoT unJPEG, Reonu combined those locations into one seamless environment.
You can move through the entrance, into the Market, down the back alley and toward the Temple of Time without hitting the original loading screens. Even details such as the changes in music volume between those areas are being preserved.
That’s the sort of change that could easily make an old game feel strangely modern, but what’s impressive here is how little the project otherwise seems interested in modernizing it. The blocky geometry, textures and overall presentation still look at home beside Link’s original N64 character model.
The Really Impressive Part: It Runs on a Nintendo 64
It would be one thing to rebuild these scenes for a modern PC port. Reonu is designing OoT unJPEG to run on real Nintendo 64 hardware as well.
That has created a considerably bigger technical challenge.
Replacing a static background with dozens of actual 3D objects puts additional strain on hardware that was already being pushed hard in 1998. To keep Castle Town running at an acceptable level, Reonu wrote custom CPU culling code that determines which portions of the environment need to be processed based on Link and the camera’s position. Buildings also use lower-detail models when viewed from farther away on the N64 version.
There are some compromises when using the free camera on original hardware, including more aggressive NPC culling at longer distances. Reonu says those restrictions aren’t necessary when using the original fixed camera, on an emulator, or eventually through the PC version.
The N64 ROM hack is also expected to support widescreen, something that becomes much more practical once the old fixed pre-rendered images are replaced with environments the game can actually draw beyond the original frame.
OoT unJPEG Is Also Planned for Zelda 64: Recompiled
There are currently two versions planned.
One will be a ROM hack capable of running on original Nintendo 64 hardware, while another will be released as a mod for Zelda 64: Recompiled once that project adds Ocarina of Time support.
Zelda 64: Recompiled currently supports Majora’s Mask and lists Ocarina of Time among its planned features. The project turns the original N64 game into a native PC application while allowing additions such as high frame rates, widescreen support, modern controls and extensive modding capabilities.
That version of OoT unJPEG won’t have to operate under the same strict N64 hardware limitations, so buildings can remain at full detail regardless of distance.
And Castle Town Was Intentionally the Hard Part
Reonu isn’t planning to stop at the Market.
The eventual goal is to replace every pre-rendered area in the game, including houses and shops. Link’s house is among the locations planned after the current Castle Town work is polished.
Starting with Castle Town was deliberate. It’s one of the largest and most technically demanding collections of pre-rendered scenery in the game, so Reonu decided to tackle the difficult part first.
That makes the progress shown so far pretty encouraging.
There is currently no release date for OoT unJPEG, and the project remains a work in progress.
The timing is also interesting. Nintendo itself is preparing a new version of Ocarina of Time exclusively for Nintendo Switch 2, currently scheduled for sometime in 2026. But OoT unJPEG is chasing a completely different idea.
Rather than imagining what Ocarina of Time should look like nearly 30 years later, it asks a much more specific question: what if the Nintendo 64 had been able to render all of Hyrule in 3D back in 1998?
Judging by Castle Town so far, that’s a version of Ocarina of Time we’d very much like to explore.
