[demo] SNES Sonic

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lidnariq
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Re: [demo] SNES Sonic

Post by lidnariq » Sat Oct 17, 2020 11:35 pm

(No. Megadrive is always 1 (SMS backwards compatibility mode) or 2 layers of 4bpp video. )

creaothceann
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Re: [demo] SNES Sonic

Post by creaothceann » Sun Oct 18, 2020 1:27 am

lidnariq wrote:
Sat Oct 17, 2020 11:55 am
Pseudo-HiRes works in modes 0-4.
Mode 7 too, probably.
My current setup:
Super Famicom ("2/1/3" SNS-CPU-GPM-02) → SCART → OSSC → StarTech USB3HDCAP → AmaRecTV 3.10

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Señor Ventura
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Re: [demo] SNES Sonic

Post by Señor Ventura » Sun Oct 18, 2020 3:20 am

Nikku4211 wrote:
Sat Oct 17, 2020 10:37 pm
Señor Ventura wrote:
Sat Oct 17, 2020 3:45 pm
In mode 5 you have the same color depth with two planes than megadrive (4BPP and 2BPP).
Mega Drive uses 2BPP graphics too?
4BPP for sprites, 4BPP for the first bitplane, and 2BPP for the second bitplane.
lidnariq wrote:
Sat Oct 17, 2020 11:35 pm
(No. Megadrive is always 1 (SMS backwards compatibility mode) or 2 layers of 4bpp video. )
2 bitplanes of 16 colors per tile, and 4 colors per tile.


edit: ok i have to take a look, i'm doubting now.

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TmEE
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Re: [demo] SNES Sonic

Post by TmEE » Sun Oct 18, 2020 4:00 am

MD (and SMS for that matter) has no sort of support for anything but 4bpp tiles, all the BGs and sprites use same data format.

Maxwelthuthu
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Re: [demo] SNES Sonic

Post by Maxwelthuthu » Sun Oct 18, 2020 1:55 pm

The most similar background mode to Genesis is Mode 2.
As it have 2 4BPP backgrounds and column scrolling\offset per tiles support.
Actually, a even better one, as it can scroll every 8 pixels instead of 16 on Genesis.
That can create some smooth effects.
https://youtu.be/03Qgz5wbiRE?t=4473

https://youtu.be/yAdXa4chEks?t=1076

creaothceann
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Re: [demo] SNES Sonic

Post by creaothceann » Sun Oct 18, 2020 4:18 pm

That helicopter is really nice!
My current setup:
Super Famicom ("2/1/3" SNS-CPU-GPM-02) → SCART → OSSC → StarTech USB3HDCAP → AmaRecTV 3.10

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Señor Ventura
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Re: [demo] SNES Sonic

Post by Señor Ventura » Sun Oct 18, 2020 4:21 pm

Maxwelthuthu wrote:
Sun Oct 18, 2020 1:55 pm
The most similar background mode to Genesis is Mode 2.
As it have 2 4BPP backgrounds and column scrolling\offset per tiles support.
Actually, a even better one, as it can scroll every 8 pixels instead of 16 on Genesis.
That can create some smooth effects.
https://youtu.be/03Qgz5wbiRE?t=4473

https://youtu.be/yAdXa4chEks?t=1076
Do you mean every row of tiles instead of each two row of tiles?.

CaptainNebbe
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Re: [demo] SNES Sonic

Post by CaptainNebbe » Sun Oct 18, 2020 7:56 pm

93143 wrote:
Thu Aug 13, 2020 3:30 am
CaptainNebbe wrote:
Wed Aug 12, 2020 6:34 pm
It’s accurate. The multiplications are free in Snes
You could perhaps make that claim in regard to actual Mode 7 display processing, but the CPU can't use the results so it's not relevant for general computing. In order to use the PPU multiplier for general computing, you have to interact with MMIO registers, and since the 65c816 is not superscalar, this operation cannot be considered "free" in any useful sense.

Señor Ventura wrote:
Thu Aug 13, 2020 2:17 am
I think the snes has not divisions, at least not that fast as the multiplications from the ppu1
It has a 16-bit ÷ 8-bit unsigned divider on the CPU die. It works like the 8x8 unsigned multiplier, except that you have to wait 16 cycles instead of 8 to get the answer.

(The SPC700 actually has multiply and divide instructions. This means that multiplication and division are interrupt-safe on the SPC700, which is totally irrelevant because there are NO interrupt sources connected to the chip... Also, unfortunately the audio system is off on its own and hard to communicate with, so it's a bit silly to try to use it as a math coprocessor...)
As i understand, the 65816 at 3.58mhz possibly equals to an 68000 at 5.5 mhz, so the difference comes to be to an 30% of performance
It's a bit of a controversial question, since it's hard to come up with any sort of universal comparison. The result of a performance comparison depends on the task being used as a benchmark, as well as on who's programming each chip...
All of that is false as it CPU CAN use the results and it IS relevant for general computing. The 65c816 IS superscalar the operation CAN be considered free.

CaptainNebbe
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Re: [demo] SNES Sonic

Post by CaptainNebbe » Sun Oct 18, 2020 7:56 pm

Señor Ventura wrote:
Sun Oct 18, 2020 4:21 pm
Maxwelthuthu wrote:
Sun Oct 18, 2020 1:55 pm
The most similar background mode to Genesis is Mode 2.
As it have 2 4BPP backgrounds and column scrolling\offset per tiles support.
Actually, a even better one, as it can scroll every 8 pixels instead of 16 on Genesis.
That can create some smooth effects.
https://youtu.be/03Qgz5wbiRE?t=4473

https://youtu.be/yAdXa4chEks?t=1076
Do you mean every row of tiles instead of each two row of tiles?.
Genesis doesn’t scroll 16 pixels. The Snes can.

lidnariq
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Re: [demo] SNES Sonic

Post by lidnariq » Sun Oct 18, 2020 9:14 pm

CaptainNebbe wrote:
Sun Oct 18, 2020 7:56 pm
All of that is false as it CPU CAN use the results and it IS relevant for general computing. The 65c816 IS superscalar the operation CAN be considered free.
... do you even understand the words you wrote?

Here's an article you should read: https://en.wikipedia.org/wiki/Superscalar_processor

Maxwelthuthu
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Re: [demo] SNES Sonic

Post by Maxwelthuthu » Sun Oct 18, 2020 11:15 pm

Señor Ventura wrote:
Sun Oct 18, 2020 4:21 pm
Do you mean every row of tiles instead of each two row of tiles?.
Yes.

Image

Image

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tokumaru
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Re: [demo] SNES Sonic

Post by tokumaru » Mon Oct 19, 2020 6:30 am

Señor Ventura wrote:
Sun Oct 18, 2020 3:20 am
4BPP for sprites, 4BPP for the first bitplane, and 2BPP for the second bitplane.
I don't know where you're getting your information from, but both background planes are 4bpp on the Genesis.

bd90492
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Re: [demo] SNES Sonic

Post by bd90492 » Wed Oct 21, 2020 5:31 am

Oh ok. I thought it would work. But do you remember me from YouTube. Brian the animator and memes?

turboxray
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Re: [demo] SNES Sonic

Post by turboxray » Wed Oct 21, 2020 12:32 pm

bd90492 wrote:
Wed Oct 21, 2020 5:31 am
Oh ok. I thought it would work. But do you remember me from YouTube. Brian the animator and memes?
Do you bot, sir?

bd90492
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Re: [demo] SNES Sonic

Post by bd90492 » Wed Oct 21, 2020 3:57 pm

?

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