Seeing Riven (1997) Differently
Part 2: Jungle Island's Patches, Tay, Age 233, and Prison Island
by Twitch
with help from Guillaume Lethuillier
Update: Guillaume's Riven Diffs Explorer is now available on Github! (This tool is described more thoroughly in Part 1)
In the last article, we covered a great many of Jungle Island's diffs. However, few of those diffs involved patches. Guillaume's tool does not currently show differentials for patches; because they are smaller than a full frame, the tool would need more information to know where the patches even go, which would require extensive work in reverse-engineering the Mohawk engine in order to achieve. However, this isn't a huge problem: patch diffs can still be compared manually, just without the helpful automation or the differential highlighting provided by Guillaume's tool.
As it turns out, Jungle Island has a great deal of patches. They are used extensively in and around the village, and for good reason. The state of the five submarine docks, the submarine elevator, and the wahrk gallows can all be seen from many many places, and patches are an efficient way to deal with this problem. However, the large number of patches also means a large number of new anomalies. Later in the article, I will also cover all the anomalies in Tay, Age 233, and Prison Island.
Most of the patches on Jungle Island relate to the five submarine docks. These docks have patch filenames that follow the same order as the levers in the submarine control room. From left to right:
- Dock 1: the submarine dock directly beneath the submarine elevator itself
- Dock 2: the submarine dock on the walkway entering the village, near the ladder shortcut up to the wahrk gallows prison
- Dock 3: the submarine dock at the wahrk gallows
- Dock 4: the submarine dock leading to the dock control levers
- Dock 5: the submarine dock at the schoolhouse
The internal names of the patches use these same numbers (eg. 's5' for a dock 5 patch). For ease of viewing (and in preparation of the animations), I have also prepared images where the patches are applied directly to the base render. In these cases, the patches have been placed manually by hand, and therefore might appear slightly differently from how they would in-game (patches in-game are sometimes not perfectly aligned with where they should be). However, this doesn't change the nature of the anomalies themselves.
Additionally, Jungle has recurring patches labeled 's6' for showing the submarine raised on its starting elevator, and 's7' for showing the wahrk gallows closed.
With that out of the way, let's begin.
A number of patches are used in the rebel cave to show individual totems lowered (up until the point the puzzle is solved). However, none of the reflections in the water are altered by these patches.
In J159, a patch is used to show dock 1 extended. However, in the patch, the dock isn't actually extended, but instead is incorrectly occluded, making it appear in the foreground of the cliff where it's embedded. In J168 and J171, the dock 1 patch appears correct, but the base renders have the dock in the wrong spot.
J332 has an 's6' patch showing the submarine still in its dry dock. However, as J332 is inside the dock control room, it's impossible to actually get to this spot without using the submarine, making this patch impossible to see in-game. Furthermore, in both J332 and J259, dock 5 (the schoolhouse) has a drastic change in lighting when the patch is applied to show it extended.
In J463, the patch showing the submarine elevator doesn't extend far enough down, resulting in the bottom of the submarine elevator being cut off.
J469 has patches for both dock 1 and dock 2. However, from this perspective, dock 2's patch completely covers dock 1. In-game, the patches are applied in the incorrect order, meaning that dock 1's extended patch can only be seen when dock 2 is retracted. If the patches are instead layered in the correct order, they appear to work correctly.
In J476, the dock 2 ladder is at the wrong angle compared to the dock itself. Also, the dock platform doesn't move at all when the dock is extended. Unlike most other dock patches, this particular cell has the dock extended by default, and uses a patch to show it retracted.
Normally, the wahrk gallows iris and dock would use two different patches, s7 for the iris and s3 for the dock. However, J507 only has a single s7 patch for both. As a result, the actual state of dock 3 is irrelevant here; if the gallows is closed, dock 3 will appear extended, and vice versa.
J557 has a few oddities. As one of the few places where you can look down and potentially see the submarine, there are more patches here than usual. By default, the base render shows the submarine at dock 1, and uses a patch (not shown here) to either hide it or flip it the other direction, which is why some of these views appear to have two submarines. However, it's the patches for dock 2 and the gallows which have anomalies of interest:
Most notably, the submarine patches at dock 2 appear to have a blue light inside the sub, along with no hatch. Furthermore, the submarine patches overlap the dock 2 patch, making the ladder appear shorter than it should be. This is strange considering that it should be impossible to exit the submarine at that spot if the dock isn't extended in the first place. Furthermore, when the gallows is closed, there appears to be more stuff visible beneath the outer ring of the gallows.
Every one of the remaining Jungle Island cells we will cover have one of two recurring anomalies, those being impossible-to-see states for dock 3 (the gallows) and dock 4 (the dock control room). The dock control room is impossible to leave without extending dock 4 first, but in most cases, dock 4 is extended by a patch, resulting in a great number of anomalies where the base render shows an impossible-to-see retracted dock 4, and the extended dock 4 patch would normally always be visible in-game. Similarly, there are a few places where dock 3 can be seen retracted while standing at the bottom of the wahrk gallows; since you can only reach the bottom of the gallows via submarine, these are also impossible to see in-game.
In J162 and J165, along with the dock 4 anomaly described above, the patches showing dock 1 extended is both incorrectly positioned and incorrectly occluded.
In J505, there is another impossible dock 4. Also, the submarine elevator lever doesn't move when the submarine elevator patch is applied.
In J561, there is another impossible dock 4. Also, dock 2 appears longer than it does normally. Furthermore, the submarine elevator is incorrectly occluded, making it visible through the cliff face.
J707 has another impossible dock 4. Also, when the gallows is open, a pole disappears.
In J479, dock 4 appears to get narrower in the impossible-to-see retracted state.
J704 and J275 both have impossible-to-see retracted dock 4s, each with incorrect occlusion in one state or the other.
J282 have impossible-to-see docks 3 and 4. Furthermore, both dock 3 and dock 4 are occluded incorrectly; dock 3 when retracted, and dock 4 when extended.
J283 has a patch for dock 4, but the dock in this patch is in the exact same spot as in the base render. Therefore, if this was possible to see in-game, the only difference between the two states would be the difference in dithering, barely visible in the differential animation.
Cells J680, J682, J683, J684, J687, J696, J698, J706, J720, J735, J466, J286, J274, and J471 also have patches showing dock 4 extended, and impossible-to-see base renders with dock 4 retracted.
Similarly, cells J272, J276, J278, J279, and J280 have patches showing dock 3 extended, and impossible-to-see base renders with dock 3 retracted.
We've finally covered every anomaly on Jungle Island. We now move on to Age 233, which has a surprising number of anomalies despite being one of the smallest locations in the game.
Shadows from the bars visible in the differential highlights of O51
In cell O3, the door changes to match the Gehn FMVs. In addition, in O3, O5, and O6, the FoV of the background changes. Also, the books move, and some of the textures on the books themselves seem different. In addition, in O6, the chair looks different, and seems to have different shadows.
In many cells, the lights on the book pedestals move when the bars move. Some of the lights aren't properly occluded by the bars. Also, the floor in the center sometimes moves a little bit.
in O54, the lever on the left appears to disappear, along with the FoV and book changing. Meanwhile, despite the other changes to the scene, the lights don't move at all.
In O57, along with the FoV and books changing, you can see a piece of the floor clipping into the ladderwell. This crescent of floor clipping visibly in the ladderwell is visible in other places as well, but here the diff makes it especially noticeable. Plus, despite the FoV changing, the lights don't move at all.
O88, the cell containing Gehn's 233 journal, contains a number of splices. The first diff here shows page 1 compared to page 11, where most of the scene is re-used except with different writing on the paper. The second diff, page 2 vs page 3, is less similar, except the differential highlights show a clear splice on the timepiece. Oddly, flipping through all the pages in the journal shows that there are 2 different reflections on the timepiece, easily visible in the third diff (pages 1 and 2).
In cell O8, the patch that moves the music player button also moves some bricks behind it.
In cell O45, the music player button patch appears to have much redder lighting.
Cell O20 and O30 have two different base renders for whether the furnace is on or off. However, both cells also have small patches over the oven window showing the oven on. This appears to be in order to improve the color definition of the oven window. In-game, the O30 patch is used correctly, but the O20 patch is never used.
Cells O26 and O31 each have two patches for when the cage is lowered, one with the pedestal lights on and one with the lights off. In the patches with the lights on, parts of the bars are still visible near some of the lights, probably resulting from various splices to avoid re-rendering the lights.
On to Prison Island. As expected, such a small area has few anomalies.
After rescuing Katran, she disables the elevator controls at P29. The handle at the top of the screen also moves slightly.
Similar to other domes, in P39 there are occlusion problems on the hinge on the right side. Also, when the dome is open vs closed, the color of the viewfinder changes, likely due to changes in the color table caused by the dome itself.
In P41, the viewfinder color changes again, though less egregiously; this seems to prove that the color changes in the last anomaly were purely differences in the available colors. Also, a dark line appears along the horizon.
Finally, to close out the article, there are 2 anomalies in Tay:
In R6, the shadows near the books change when the books are present.
In R8, there are two different versions of the book back to Riven. The first one matches the FMV and is only visible immediately after Nelah places it there. After the player moves, the second book is used from that moment on.
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