Cobra Triangle, oddities and boundary break

[dark_lord_zagato]

I found some interesting things while mapping Cobra Triangle. I've set aside some unedited maps to show it off.


This game seems to store the map data for stages 1 and 9 in the same general area inside the ROM. This isn't just a palette swap, it's two different stages in one giant map and they bleed into each other. This led to a fair amount of confusion when I started this project but by the time I was done with stage 9 I knew what was going on.

The stages use different palettes and different tile sets, but you can see how the course is the same. You can also see that i've cleaned up the regular maps quite a bit. This is because the stuff i've cleaned up is WAY out of bounds and looks really bad if left in place.

The NES cartridges don't have a lot of storage and there's a lot of big stages in this game, so perhaps the bigger maps share the same area in the ROM to save space?

Stage 14 contains the map for stages 11 and 18, Shoot The Targets. Yes, these are the same map, but you travel the lower path in 11 and the upper path in 18.


If you've come here from The Cutting Room Floor and want to verify this information for yourself i'll tell you how to boundary break.


My codes:

037D:FF Walk through walls. Toggle this on for a few frames and then turn it back off. You can go outside the normal boundary of the stage but you can't cross the finish line anymore.

0701:?? Set the value to 00 to remove the autopilot in Shoot The Targets. Set the value to 07 to stop the rapids in Reach The Finish and Jump The Waterfall.

0348:?? This is for jump height, but if you set the value to 01 the screen will scroll straight up. If you hit a jump and set the value to F8 you can just fly over everything.



General codes:

00B9:1A Invincible
0714:3B Infinite Time

[Cyartog959]

Very astute you figured that out. I was astounded about that discovery, I'll admit.

To be honest, upon watching Strafefox's videos about how past video games were made before the vast tech upgrades, the tileset amounts, then-expensive memory amounts for in-house dev workstation computers, and memory bank switching were very minimal and common in their time, and the NES carts were quite minimal in space, even with expansion chips to up its capabilities by notches, never very close to even half of a Gigabyte for a game, it is justifiable to see such bypasses had to be compromised to meet within the very tight limits of the NES then.

Still, your boundary breaking to gather the whole view of the maps in that game were rather impressive.

I can leave such videos for you to watch later, if you want. Maybe you'll learn much about those limits and bypasses people utilized then.

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