News: 11 March 2016 - Forum Rules
Current Moderators - DarkSol, KingMike, MathOnNapkins, Azkadellia, Danke

Author Topic: Megaman 1 Checkpoints  (Read 1003 times)

Timaeus

  • Jr. Member
  • **
  • Posts: 50
  • Noel <3
    • View Profile
Megaman 1 Checkpoints
« on: September 29, 2015, 10:33:59 pm »
  With rock and roll , I´ve finished all 10 levels in the game , now I have to fix the checkpoints , however I´m could find it how .  I already know about hexing , enemy checkpoints , seting the checkpoint and activate point in the same screen , set the scrolls and sprites , setting the checkpoint with the room order editor and the scrrol editor , this kind of thing . I also have some notes that I found in another forum and some others I found myself , which have some informations about it

 
Spoiler:
Cut stage

$153B0 ScrollPos                  Checkpoint scroll byte numbers
$153DF CheckPo1                   Table of values defining the slot number of the last enemy on the midpoint page (second checkpoint)
$1540A RoomOrderFix1Check         A table containing the first screen ID in the scroll byte selected for the checkpoint
$15422 RoomOrderFix2Check         A table containing the last screen ID in the scroll byte selected for the checkpoint?
$1C2E4 ScreenStartChk2Trig        Screen numbers which activate the checkpoint
$1C2FB RoomOrderPos               Where Mega Man respawns after dying
$1C52A BeamDown1Offset            Checkpoint y coordinates



"Checkpoint scroll byte numbers" tells the game which scroll byte to use when you start at that checkpoint. If the screen you're starting on is in the second scroll byte, you'd put 01.

The "slot number of the last enemy on the midpoint page" is calculated by just counting the sprites in the stage from the first sprite to the last sprite on the page where the checkpoint is (the first sprite in the stage is in slot 00). This tells the game how far into the sprite data to look for sprites that are 'active' when you beam in.

Everything else should be pretty self-explanatory. I think there's also something related to special objects, but it's not in my notes (but there is something about changing $150F7 to 4CF690 that might have to do with special objects)... Anyway, with this data, you should be able to get your checkpoints working just fine using a hex editor. The only thing I feel I need to add is that you must start Mega Man off at the beginning of a scroll area; if you start him off in the middle or end of a corridor, the game won't know to load any of the graphics for the prior screen, so scrolling backward will cause background graphic problems (you'd have to add a special case to the background loading routine or rewrite it entirely (depending on what you're trying to do) in order to make that work).

 About the Checkpoint scroll byte numbers thing , the first checkpoint is located in a up scrolling (like the original game) and the scrool byte is 80 (at least is what I could find) , so I put 80 , and it doesn´t work .

  I count all the sprites before the checkpoint and change the number , but the result was the same . Actually it only worked after setting the enemy checkpoints in rock and roll .

 I couldn´t find what ´´Where Mega Man respawns after dying ´´ and ´´Checkpoint y coordinates ´´ is supposet to be (in hex , is shows 00 and 94 , respective) .

 

 This is the first checkpoint , showed in rock and roll . As you can see , to reach the next screen , you must go up . So is a up scrolling


 
 
 Here is all the scrolls used in the level , with the checkpoint scroll circled (is writted ''up after 1'' , and disabling the simple mode shows 80 , which might be the scroll byte value)

´´Where Mega Man respawns after dying´´ apperrently doesn´t  have anything with the checkpoint , because  changing the number only affects where he spawn in the beggining of the level

The ''Checkpoint scroll byte numbers'' thing doesn´t change nothing in the checkpoint , it disabled where the level scrolls start



Here is what happens when I respawn . I PHYSICALLY appear in another screen , because as soon as I spawn , he launch himself in the wall , corrupting the scrolls order (and the respawn position is NOT messed up ,  as you can see in the first image)







Here is the screen numbers in order . I don´t know if have something to do with checkpoints but here it is

Any help will be VERY appreciated