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Author Topic: Graphics help pls  (Read 954 times)

rainbwsprinklez

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Graphics help pls
« on: December 21, 2019, 04:32:23 pm »
I'm working on DKC2 for the SNES... my current goal is editing a couple of backgrounds. Both are compressed, so I need (prefer) to use my own image. I'm kinda stuck. I don't know how to encode it or really anything in that regard... can someone help pls? I am mostly an ASM hacker and I'd like to use a static image for the end screen... right now I have it setup so I go to a blank screen. I need my image to go there.
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Cyneprepou4uk

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Re: Graphics help pls
« Reply #1 on: December 21, 2019, 05:05:02 pm »
Is it compressed when already in PPU or before that?
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rainbwsprinklez

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Re: Graphics help pls
« Reply #2 on: December 21, 2019, 05:17:24 pm »
The ROM images are compressed in the ROM, they are sent to the PPU however, uncompressed. There are routine in the CPU to decompress them.
I can easily intercept that image as it is sent from RAM. I just don't know what to send the PPU.

To elaborate, I tried the documents on this site. They are not my speed.
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Cyneprepou4uk

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Re: Graphics help pls
« Reply #3 on: December 21, 2019, 05:26:54 pm »
As I understand, you can easily avoid that uncompress routine and send necessary bytes to RAM directly. But you don't know what these bytes should look like, because you don't know how PPU works (tiles in particular). Right?
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rainbwsprinklez

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Re: Graphics help pls
« Reply #4 on: December 21, 2019, 05:48:46 pm »
As I understand, you can easily avoid that uncompress routine and send necessary bytes to RAM directly. But you don't know what these bytes should look like, because you don't know how PPU works (tiles in particular). Right?

Correct! I don't know if palette is involved or what.
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Cyneprepou4uk

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Re: Graphics help pls
« Reply #5 on: December 21, 2019, 06:25:29 pm »
Man, it would be such a pain explaining you all that  :) You definetly have to read some docs, but I can't recommend any since I haven't read them.

Basically you need to create tiles in some tile editor, like YY-CHR, then save file and copy bytes from it. You'll also need to set a palette and background nametable with attributes.

Sorry I couldn't help, maybe someone else here has more info.

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rainbwsprinklez

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Re: Graphics help pls
« Reply #6 on: December 21, 2019, 06:30:21 pm »
Oh, but you DID help.  That's more information than I had before!

December 21, 2019, 07:07:06 pm - (Auto Merged - Double Posts are not allowed before 7 days.)
Question for you... is n64 very similar? Can I learn from those docs?
« Last Edit: December 21, 2019, 07:07:06 pm by rainbwsprinklez »
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Cyneprepou4uk

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Re: Graphics help pls
« Reply #7 on: December 21, 2019, 07:50:58 pm »
No idea.

NES should be very similar.
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rainbwsprinklez

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Re: Graphics help pls
« Reply #8 on: December 21, 2019, 08:43:42 pm »
I just had an amazing idea! I found the decompressed images in ram. All i have to do is dump all those bytes to an external file, open in tlp to tweak (since it is a decompressed image after all), and insert it back in! this way, i don't have to worry about palettes and my image will still look authentic!
« Last Edit: December 22, 2019, 08:51:23 pm by rainbwsprinklez »
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