Integer Overflow Bugs

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atrueprincefanfrom18
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Integer Overflow Bugs

Post by atrueprincefanfrom18 »

There are more Integer Overflow Bugs! One is actually useless, and second one is a useful one but nobody can use that in the speedrun.

First one (Level 7) just teleports you above, there is no tile for holding, so the Kid falls down anyway.
Second one (Level 12a) does the same thing, but you lose a health, not die. However if the sword is not there your life is fully restored.

Do play my mod! https://www.popot.org/custom_levels.php?mod=0000206 ( It uses the second overflow bug in 12a :) )
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Re: Everything you should know before doing a speedrun

Post by David »

atrueprincefanfrom18 wrote: January 30th, 2020, 1:39 pm First one (Level 7) just teleports you above, there is no tile for holding, so the Kid falls down anyway.
There is another, slightly different way of doing the same, with standing jump from the bottom row instead. (See attachment.)
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atrueprincefanfrom18 wrote: January 30th, 2020, 1:39 pm Second one (Level 12a) does the same thing, but you lose a health, not die. However if the sword is not there your life is fully restored.
This one was mentioned in the thread about bugs: viewtopic.php?p=9932#p9932

That thread also has a link to a video showing an Integer Overflow on level 10.
(I know there was a video about that in the first post of this thread as well, but currently none of those videos load because jakim.pl is down.)

The health regeneration was mentioned here, by the way: viewtopic.php?p=15796#p15796 and viewtopic.php?p=15788#p15788
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Re: Everything you should know before doing a speedrun

Post by atrueprincefanfrom18 »

Wow!

Didn't know about the Overflow Bug which you posted!

Is there a topic just on Integer Overflow and a list of all those?

Would like if there's one :)
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Re: Everything you should know before doing a speedrun

Post by atrueprincefanfrom18 »

Another useless one! :P

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Re: Everything you should know before doing a speedrun

Post by atrueprincefanfrom18 »

Another Integer Overflow Bug on Level 3:


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Re: Everything you should know before doing a speedrun

Post by Norbert »

atrueprincefanfrom18 wrote: September 3rd, 2020, 12:44 pm Another Integer Overflow Bug on Level 3: [JpbWyKCsW8Q]
I don't think that's an overflow?
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Re: Everything you should know before doing a speedrun

Post by atrueprincefanfrom18 »

Norbert wrote: September 3rd, 2020, 4:41 pm I don't think that's an overflow?
It works without a SHIFT, so it might not be. But on the other hand if you watch carefully, the Kid falls from top tile and NOT from the second row of that room. Maybe try 0.25x speed.

Well, it maybe something like, the game is trying to switch to a different room and while it changes the Kid has got down to another room and the game tries to get all into the perfect room, and somehow Kid shifts to upper room?

Maybe need a debugger to see what exactly is going on. Because I'm sure the Kid falls from very top and NOT from where he should have fell.
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Re: Everything you should know before doing a speedrun

Post by Norbert »

atrueprincefanfrom18 wrote: September 3rd, 2020, 5:11 pmBecause I'm sure the Kid falls from very top and NOT from where he should have fell.
Ah, yes.
Now I see what you mean. :)
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Re: Integer Overflow Bugs

Post by David »

I've moved these posts from the Everything you should know before doing a speedrun thread, since most of these overflows are not useful for speedruns, because the prince dies after them.
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