Finally got my new monitor set up and am taking another crack at this. After 6 months I can't believe how rusty I was at playing this game! I had to watch my video a few times to remember some of the tricks used. RNG has been incredibly cruel to me in Stages 3 and 4 in regards to pass location. It seems to rarely be where I need it in Stage 3 (well under 50 percent) and the few times I've gotten it, the Stage 4 one wasn't there.
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Glad to hear that you have a working setup again.
Speedrunning isn't exactly like riding a bike. It will take some time to get back the feeling and the muscle memory, but hopefully it should go fairly quickly once you get the practice going.
I'm looking forward to hear about your progress. And please be careful with your recordings going forward. ;-)
Speedrunning isn't exactly like riding a bike. It will take some time to get back the feeling and the muscle memory, but hopefully it should go fairly quickly once you get the practice going.
I'm looking forward to hear about your progress. And please be careful with your recordings going forward. ;-)
Don't know if you already were aware, but here is some information about the pass locations.
The RAM-address governing the pass locations is stored in $7B8. In the first level, it should be 1. In levels 3 and 4, the value should be 0 for the optimal locations.
From what I can read out of the code, the algorithm for determining the pass location is the following:
Some observations:
- $2A is an RNG-counter that changes every frame and depends on user input (and probably a bunch of other things as well). I don't have enough background for digging into the game code to evaluate if there are patterns in the RNG-algorithm. It's at least difficult to find any patterns by just observing how the value of the address changes.
- It should be a strict 50/50 chance for A to have the right value after the AND-operation.
- Once the level starts, the location is 100% set.
- As far as I can tell, $7B8 isn't used for anything else of relevance in the levels, so it's probably not going to be possible to get any cue about the location without actually going to the room.
Since you're not seeing the expected 50/50 chance of the pass locations in levels 3 and 4 (and your success rate looks odd for only blaming "bad luck"), I would recommend doing a few recorded playthroughs of the first two levels in an emulator. Play like you would in attempts (same route, kill the same enemies etc).
If you're still seeing the same poor rate of getting the right locations, it might mean that the value can be manipulated to some extent. Maybe you're currently manipulating it negatively (without knowing), but then it might also be possible to manipulate the rate positively? Then do the same thing but start from one of the TASes. So let the TAS play for a while, stop the movie and then play from that point in real-time. Still the same poor rate?
The RAM-address governing the pass locations is stored in $7B8. In the first level, it should be 1. In levels 3 and 4, the value should be 0 for the optimal locations.
From what I can read out of the code, the algorithm for determining the pass location is the following:
Code:
LDA #$01 (this sets the value of the accumulator (A) to 1) AND $2A (this compares the value of $2A with A and writes the result to A -> If $2A was even, A will be 0, if it's uneven, A will be 1) STA $7B8 (this writes the value in A to $7B8)
Some observations:
- $2A is an RNG-counter that changes every frame and depends on user input (and probably a bunch of other things as well). I don't have enough background for digging into the game code to evaluate if there are patterns in the RNG-algorithm. It's at least difficult to find any patterns by just observing how the value of the address changes.
- It should be a strict 50/50 chance for A to have the right value after the AND-operation.
- Once the level starts, the location is 100% set.
- As far as I can tell, $7B8 isn't used for anything else of relevance in the levels, so it's probably not going to be possible to get any cue about the location without actually going to the room.
Since you're not seeing the expected 50/50 chance of the pass locations in levels 3 and 4 (and your success rate looks odd for only blaming "bad luck"), I would recommend doing a few recorded playthroughs of the first two levels in an emulator. Play like you would in attempts (same route, kill the same enemies etc).
If you're still seeing the same poor rate of getting the right locations, it might mean that the value can be manipulated to some extent. Maybe you're currently manipulating it negatively (without knowing), but then it might also be possible to manipulate the rate positively? Then do the same thing but start from one of the TASes. So let the TAS play for a while, stop the movie and then play from that point in real-time. Still the same poor rate?
Nice find. I've always been curious how the RNG worked in this game for determining pass locations. From what you've posted, it looks like it should be quite random. I think in the long-run the stage 1 pass location has been roughly 50/50. Obviously my sample size for 3, and especially 4, is far smaller so bad luck could still be at work here. I suspect any manipulation that could be done via user input would be in the short time before the stage starts. At the end of Stage 2, I always mash the A and B buttons once my boat reaches the end to speed up the process of getting the game to move on to stage 3 - I'm not sure if doing this actually speeds it up any, but maybe I'll stop doing that and see if there's any change. Emulator monitoring is a bit beyond anything I'm interested in trying.
Mashing the A and B buttons doesn't change the value of $2A once the screen goes black. But it doesn't change the time of the transition to level 3 either. If you haven't done it yet, it could be worth to go through all the screen transitions/cutscenes to see which of the non-obvious ones can be sped up. Your level of play is far, far beyond where that type of mistake should be acceptable.
Up to you if you want to use emulators to gather additional information about the game or not. But just so you know, the tests I'm talking about could be made very low-tech. If your success rate with the pass card locations doesn't improve, it's worth keeping this option open imo.
Up to you if you want to use emulators to gather additional information about the game or not. But just so you know, the tests I'm talking about could be made very low-tech. If your success rate with the pass card locations doesn't improve, it's worth keeping this option open imo.
My lack of updates here the past few weeks aren't for lack of trying. Level 3 is cursed. It is bad enough that the pass is seemingly there well under 50 percent of the time, but when it is, the boss is kicking my butt - time and time again.
For the past 500 or so game resets, my stats look roughly like this:
-250 times making it past the Level 1 Pass
-50 times making it to Stage 2 with an acceptable time
-48 times making it to Stage 3
-15 times making it past the Stage 3 pass
-12 times making it to the Stage 3 boss
-0 times making it to Stage 4.
Seriously I don't know how many more times I can tolerate having to play Stage 1. I'm bored to tears with it.
Today the pass location in Stage 1 wasn't being kind. Was there 1 out of 4 times out of 30 or so attempts so that was aggravating enough. Then went 0 for the first 4 times into Stage 3 for pass location. Then on the 5th time, it was FINALLY there. And that was great because I was on a blistering pace. Made it to the Stage 3 boss. Perfect execution, except TWICE the boss refused to spawn on my platform.
For the past 500 or so game resets, my stats look roughly like this:
-250 times making it past the Level 1 Pass
-50 times making it to Stage 2 with an acceptable time
-48 times making it to Stage 3
-15 times making it past the Stage 3 pass
-12 times making it to the Stage 3 boss
-0 times making it to Stage 4.
Seriously I don't know how many more times I can tolerate having to play Stage 1. I'm bored to tears with it.
Today the pass location in Stage 1 wasn't being kind. Was there 1 out of 4 times out of 30 or so attempts so that was aggravating enough. Then went 0 for the first 4 times into Stage 3 for pass location. Then on the 5th time, it was FINALLY there. And that was great because I was on a blistering pace. Made it to the Stage 3 boss. Perfect execution, except TWICE the boss refused to spawn on my platform.
First of all, I've slightly modified my previous post with the pass location algorithm. It doesn't change anything of importance, but there were some mistakes that I have now hopefully corrected.
I'm honestly puzzled about the poor success rate you have with the pass in level 3. I can't see any pattern in the parity of $2A and therefore no reason for the pass locations to be anything other than 50/50. However, I have to say again that I don't have the background for digging into how $2A is calculated. I have posted about the issue on tasvideos to see if I could generate some interest. There are certainly enough people with knowledge on how to tackle this problem over there. But it's probably time-consuming even if you have the know-how, so it's far from guaranteed that anyone will look into the issue. Still, you can check out the topic if you're interested:
http://tasvideos.org/forum/viewtopic.php?p=480007#480007
I'm honestly puzzled about the poor success rate you have with the pass in level 3. I can't see any pattern in the parity of $2A and therefore no reason for the pass locations to be anything other than 50/50. However, I have to say again that I don't have the background for digging into how $2A is calculated. I have posted about the issue on tasvideos to see if I could generate some interest. There are certainly enough people with knowledge on how to tackle this problem over there. But it's probably time-consuming even if you have the know-how, so it's far from guaranteed that anyone will look into the issue. Still, you can check out the topic if you're interested:
http://tasvideos.org/forum/viewtopic.php?p=480007#480007
There has been some progress in understanding the RNG in the thread in tasvideos. To me, it still looks like it should be a 50/50 for the pass locations though. We'll see if some new information comes or if your bad luck turns.
However, I have found one minor time saver that's very easy to implement. At the end of level 2 (= roughly from when the last bridge near the end of the level appears on screen), make sure that you press and hold up, left or right. If you just stand still, I've seen the level transition be up to 1.5 secs slower. If you move back and forth, like can be natural to "celebrate" the end of the level, you're going to have a few frames between changing directions without input (unless you also press up at the same time) and end up losing time.
However, I have found one minor time saver that's very easy to implement. At the end of level 2 (= roughly from when the last bridge near the end of the level appears on screen), make sure that you press and hold up, left or right. If you just stand still, I've seen the level transition be up to 1.5 secs slower. If you move back and forth, like can be natural to "celebrate" the end of the level, you're going to have a few frames between changing directions without input (unless you also press up at the same time) and end up losing time.