My first nes game! (DemonDistrict)

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nocash
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Re: My first nes game! (DemonDistrict)

Post by nocash »

klonoa wrote:What should I do with the A,X,Y registers? and why?
Where do I start there? I hope you can follow this...
You have a NMI handler (the function that gets called automatically on vblank) in your program. And that function changes A,X,Y (and it doesn't restore the old values when it returns).

In your program that can be a problem for the code between address C390h (enable NMI) and C3B0h (endless loop). The opcodes between those addresses use the A register, but (if you are unlucky) the NMI handler could change the value in A.

"Push/pop" or "push/pull" were meant to mean the "PHA and PLA" instructions (for saving/restoring A on stack). You need that in the NMI handler, too. Otherwise unexpected things could happen.

Well, and saving X and Y is a bit more difficult... but your code is already doing that in some places... so I guess you know how to do that : )
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calima
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Re: My first nes game! (DemonDistrict)

Post by calima »

At the start of the game, with the attached screen showing, I was pressing buttons to get to the next part since it was so slow. I pressed start. When the real game began, it instantly opened the menu.

Unless I had perfect timing, the start-button press happened in this mode, not the in-game mode. For that to open up the menu likely means you didn't clear the button state between the modes.
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nocash
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Re: My first nes game! (DemonDistrict)

Post by nocash »

klonoa wrote:Still Wanna make a small cutscene where she goes on the bike and jumps the gap at the end of the road.
Ah, that is a bike... I had mistaken it as a ballerina in a red dresss who were telling me that the demonish flying-saucer had run out of petrol and that she doesn't have a key for it anyways... which seemed to make sense, too ; )
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klonoa
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Re: My first nes game! (DemonDistrict)

Post by klonoa »

nocash wrote:
klonoa wrote:What should I do with the A,X,Y registers? and why?
Where do I start there? I hope you can follow this...
You have a NMI handler (the function that gets called automatically on vblank) in your program. And that function changes A,X,Y (and it doesn't restore the old values when it returns).

In your program that can be a problem for the code between address C390h (enable NMI) and C3B0h (endless loop). The opcodes between those addresses use the A register, but (if you are unlucky) the NMI handler could change the value in A.

"Push/pop" or "push/pull" were meant to mean the "PHA and PLA" instructions (for saving/restoring A on stack). You need that in the NMI handler, too. Otherwise unexpected things could happen.

Well, and saving X and Y is a bit more difficult... but your code is already doing that in some places... so I guess you know how to do that : )
Oh like that, but that's only a concern when it is actually doing something in the main loop right?
klonoa
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Re: My first nes game! (DemonDistrict)

Post by klonoa »

calima wrote:At the start of the game, with the attached screen showing, I was pressing buttons to get to the next part since it was so slow. I pressed start. When the real game began, it instantly opened the menu.

Unless I had perfect timing, the start-button press happened in this mode, not the in-game mode. For that to open up the menu likely means you didn't clear the button state between the modes.
Ahh like that.
Thanks, I understand now.
klonoa
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Re: My first nes game! (DemonDistrict)

Post by klonoa »

nocash wrote:
klonoa wrote:Still Wanna make a small cutscene where she goes on the bike and jumps the gap at the end of the road.
Ah, that is a bike... I had mistaken it as a ballerina in a red dresss who were telling me that the demonish flying-saucer had run out of petrol and that she doesn't have a key for it anyways... which seemed to make sense, too ; )
Haha guess that's something to work on. :lol:
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gauauu
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Re: My first nes game! (DemonDistrict)

Post by gauauu »

Great job, thanks for sharing.

I had trouble in a few spots lining up in exactly the right place to trigger a door, but other than that, everything worked quite smoothly.
klonoa
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Re: My first nes game! (DemonDistrict)

Post by klonoa »

gauauu wrote:Great job, thanks for sharing.

I had trouble in a few spots lining up in exactly the right place to trigger a door, but other than that, everything worked quite smoothly.
Thanks!

Lemme guess, at the gas station? :lol:
drludos
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Re: My first nes game! (DemonDistrict)

Post by drludos »

I managed to survive too!
Congrats on the game, it's a really cool adventure game. I like the overall "end of the world" mood to it, and the puzzle were logical but still a bit challenging. The exploration part was well balanced too IMHO.

An ending cutscene or more details about what happen next in text form would be cool - what happen after we escape the city? Honestly, you do have laid the background to make a larger game with a more detailed story: what kind of "demons" were released? Why? and can the player "save the world" and send the demons back to where they came from?
Maybe you should do a "chapter 2" as a sequel ;).

Out of curiosity, what did you use to make it? (ASM, C, NesMaker, etc.?)
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klonoa
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Re: My first nes game! (DemonDistrict)

Post by klonoa »

drludos wrote: Sat Nov 23, 2019 6:11 pm I managed to survive too!
Congrats on the game, it's a really cool adventure game. I like the overall "end of the world" mood to it, and the puzzle were logical but still a bit challenging. The exploration part was well balanced too IMHO.

An ending cutscene or more details about what happen next in text form would be cool - what happen after we escape the city? Honestly, you do have laid the background to make a larger game with a more detailed story: what kind of "demons" were released? Why? and can the player "save the world" and send the demons back to where they came from?
Maybe you should do a "chapter 2" as a sequel ;).

Out of curiosity, what did you use to make it? (ASM, C, NesMaker, etc.?)
Thank you so much! :)

I still want to make one or two levels that will slowly explain everything.
Think of the first resident evil where you start in a mansion with zombies and later find out why there are zombies.

I made it in ASM.
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Roni
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Re: My first nes game! (DemonDistrict)

Post by Roni »

I just discovered this game and I'm blown away. as soon as I began playing I was immersed in it and felt the labor and heart that went into it, especially the music. I get the impression that you spent a lot of time playtesting and perfecting it.
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Controllerhead
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Re: My first nes game! (DemonDistrict)

Post by Controllerhead »

I Survived!

Reallllly good theme / environment. Music fits. Graphics are cool. Gameplay works for what it is, and seems polished. If it were longer, i certainly would have kept playing. Thanks for a little taste of LucasArts! I hope there is a next project, or even an extension to this one, either way i'm excited. Keep it up!
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NeverCameBack
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Re: My first nes game! (DemonDistrict)

Post by NeverCameBack »

Amazing game! The music is awesome.. I hope my first game is even 10% as good as this - myself am just getting through half the NerdyNights tutorials. What exactly are you in school for that this would be your project?
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qbradq
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Re: My first nes game! (DemonDistrict)

Post by qbradq »

I survived but I feel like there's things I'm missing. Great work and thanks for sharing!
klonoa
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Re: My first nes game! (DemonDistrict)

Post by klonoa »

Thanks for all the love! :beer: :D
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