$${\color{red}THIS\quad DOES\quad NOT\quad COME\quad WITH\quad YOSEMITE}$$

YOU MUST PROVIDE YOUR OWN COPY OF YOS.DGO!

This mod just serves as an easy way to play the level in OpenGOAL, with minimal changes/additions.

(Pre-) Installation

• BEFORE installing the mod
  • Make sure you have a copy of YOS.DGO (mount the September 2001 Preview ISO or open it with 7Zip/WinRAR, and copy this file from the DGO folder)
  • Go to the Jak 1 launcher page, and click Advanced -> Open Game Data Folder
  • Go into iso_data/jak1/DGO, paste your copy of YOS.DGO here
• Install mod
• Have fun

Speedrunners - you can find an updated autosplitter for splitting on all 69 orbs here (add to your layout as Scriptable Auto Splitter)

Background

Yosemite (AKA Sierra, Unsnowy Mountain, or Rock Lake) is an unfinished level for Jak and Daxter that never made it into the game.

From an interview with Evan Wells in 2011:

We also went through a lot of iterations with our engine as far as how we were going to render those big vistas. The very first three or four environments that we modeled and put a lot of work into ended up on the cutting room floor because it was just going through the early stages of grappling through PlayStation 2 hardware. It’s part of the process of getting your feet wet with new hardware. We had a level we called “Yosemite” – this giant half-dome mountain in Yosemite that we modeled with a forest at the base – and we really tried to get it into the final game. We came back to it as one of the last levels to see if we could apply some of the knowledge that we had accumulated on previous ones to see if we could shoehorn it in the last second, but it was too late.

A version of the file YOS.DGO - which contains the level's visuals, collision, actor data, etc - was found on the September 2001 Preview build.

It's worth noting that this build of the game is missing the configuration and code files to actually load in the Yosemite level. The YOS.DGO file just happened to be included on the build still, likely an oversight.

More information can be found in the Technical Wiki here.

Mod Info

This mod aims to let you explore Yosemite with minimal changes, to keep the experience vanilla.

• There is no OpenGOAL custom level at work here. The mod extracts and loads the level as if it were a vanilla level
• All of the actor placements - the orbs, crates, cannon, etc - were done by Naughty Dog and come directly from the YOS.DGO file. One orb is inside the mountain wall, out of bounds.
  • Some actors, such as cavedrip and cavewater, will not spawn, as the associated code files as well as the art group files are missing (these would have been separate from YOS.DGO)
  • The crates are actually an unknown type called plainbox, which would normally not spawn either - the mod has changes to render them as crates, assuming plainbox is just an early name for the crates
  • There is a water volume where the lake is intended to be, but the format is different and doesn't currently spawn. I may try to patch this up at some point in the future so that it at least functions like a water volume
  • The zoomer textures are a bit different / incorrect, possibly because of a slight change in the tpage format during the ~3 months between this copy of YOS.DGO vs the final game release
• The checkpoint IS something added for the mod, since no known builds have the level-load-info code for Yosemite, which would define the checkpoint(s).
• I chose to reuse the post-final boss music for this level, but there was a track "Unsnowy Mountain" composed and published for this level if you're interested
• The "ROCK LAKE" text is present but unused in the final build of the game, so I chose to have the mod display that as the level name in the pause menu

Luminar has an alternate OpenGOAL build for Yosemite which adds in Scout Flies and Power Cells through a custom level, which you can check out here.

Misc

While unused in this mod, there is more unused text leftover in the final build that likely related to Power Cells within this level, such as:

• FIND THE RED VENT SWITCH
• PROTECT THE MINERS' GEMS IN THE STUMP
• REACH THE TOP OF THE MOUNTAIN
• STOP THE DRILLING LURKERS
• DEFEAT THE CAVE BATS

Some concept art relating to this level - you can see the drilling lurkers corresponding to the above Power Cell text. There's a theory that they planned to have boulders falling down the mountainside shown here, and instead later reused the idea for the avalanche in Jak II's mountain temple area.

In debug mode, if you display Volcanic Crater (Load > Display > village3) and turn on Actor > Ambient Sound Marks, you can actually see a trail of lava sound effect "bubbles" leading from the miner's gem/cave into Yosemite. These exist in the final build of the game, they don't come from adding in YOS.DGO!