The NES vs. its contemporary competition

[OneCrudeDude]

I actually forgot about the Super Cassette Vision. That's quite an amusing console, but even if it came a year after the Famicom, the Famicom was space age technology. I guess it faded to obscurity because, tech-wise, it just couldn't hold it's own.

[rainwarrior]

The VRC7 is based on the same chip as the SMS FM, but it has less features. The YM2413 in the SMS has a choice of extra channels or a percussion mode, not present on the VRC7. The built-in patch set is also different.

[ccovell]

...not counting the PAULA in the 2600, that lovely piece of detuned nightmare...

Oi! Leave the fantastic PAULA chip out of this! Thanks to it, the Amiga blew away the competition for nearly a decade.

The 2600 had the TIA chip for tone generators.

About graphics, the 7800 and C64 (Atari 800, etc.) like many early-80s computers, had 160-pixel wide graphics in high-colour mode, and 320-pixel graphics in monochrome/ 1 bitplane mode. However, over time new screenmodes have been discovered/hacked on the C64 such that you can now have 320x200 full 16-colour screens, usable for cinemas, title screens, etc. (no CPU time for in-game stuff beyond a scroller.)

[Sik]

Actually the C64 was even weirder. You could have either low resolution (doubled pixels) tiles with 4 colors or high resolution (normal pixels) tiles with 2 colors (makes sense, in both cases the bandwidth usage is the same). This could change in a per tile basis, so you could mix both kind of graphics at the same time.

[lidnariq]

It's really amusing going and flipping back and forth between the VIC-1 (VIC-20) and VIC-2 (C64) and seeing what they changed and didn't change.

[jayminer]

Having done some coding for the C64 I felt I would chime in here.

One huge advantage the NES has over something like the C64 is how cheap scrolling is. On the C64 you could only scroll 7 pixels and then you needed to reset the scroll and move all the tiles. The VIC allowed the adress to "Screen RAM" to be moved so you could double-buffer this to help spread the work out over several frames, but "Color RAM" was at a fixed location so it couldn't be double buffered and needed to be completely rewritten on the frame the scrolling is reset.

There are tricks to get around this, something called VSP (Variable Screen Positioning) which tricks the VIC chip into actually scrolling more than 7 pixels, and was used in Mayhem in Monsterland and probably some other games, and also quite a few demos. Unfortunately this trick has the nasty habit of crashing a few C64s.

I would say the most fun thing about the C64 is the fact that the VIC allows itself to be tricked into doing things it wasn't really meant for. Things like multiplexing sprites by moving them after they have been drawn, changing palettes midscreen, changing "videomode" midscreen are all simple to do.

And when it comes to the palette, I think the C64:s 16 color palette is good for what it is. Sure the colors are a little "muted" and not as bright as most other systems, but that helps things out, there are intensity pairs of each color and you could usually use the grays as "inbetween" colors which actually looks better than one would imagine. There are a few examples in these pictures.

[OneCrudeDude]

Regarding Mayhem in Monsterland, I'm more impressed with the massive title screen taking up most of the screen, and then there being a background behind that. Was this by chance done by taking advantage of the C64's massive 64K RAM, by drawing unique tiles to give the illusion that there's two layers?

[tepples]

As I understand it, the Commodore 64 has eight sprites, each 24px wide, all of which can be on one line. This allows 192px = 60% overdraw. Sprites can be reused multiple times on the screen. If the title screen is what I think it is based on Google Images, 192px wide is about right.

[Sik]

Yeah, looking at that it seems to be sprites (C64 sprites can have 3 colors of which 1 is unique to each sprite and 2 are shared by all, albeit in that case the pixels get doubled in width, which is what happens here).

EDIT: also I need to recheck again but I think that in that video the HUD was edited because it's not showing the entire screen (I think the bottom of the HUD is trimmed out, which is where the text is actually supposed to be)

[OneCrudeDude]

I also noticed that some graphics appear to be blown up to about twice their size, especially the title screen. Is that part of the C64's hardware, or is that an intentional design choice?

[jayminer]

You can expand sprites in X, Y or both directions, so you can actually fill the entire screen and a little more with sprites, very pixly sprites but still!

I found this video that shows off a few games that has some huge sprites

[OneCrudeDude]

Interesting, what purpose would this serve? Probably to save memory by drawing something small and then expanding it in software, correct? I'm certain that this would still eat up the sprites per scanline limitation, but the C64's is MUCH more lenient than the NES or SMS's.

Speaking of sprite limits, what about the Atari 7800 or MSX2? Allegedly the 7800 could push loads of sprites around with minimal, if any flicker, so either it was 'immune' to flicker, or it just had a high upper limit. The MSX2 might be more along the lines of the NES and SMS, seeing as how Hideo Kojima designed Metal Gear the way it is due to the hardware. I'm certain he went with an overhead play area as that would be less likely to induce flicker.

[lidnariq]

Speaking of sprite limits, what about the Atari 7800 or MSX2? Allegedly the 7800 could push loads of sprites around with minimal, if any flicker, so either it was 'immune' to flicker, or it just had a high upper limit.

I found my way over to this wiki, where someone's gone to some effort to explain what's going on.

My best interpretation, having only spent a few minutes to look through it:
The 7800 is approximately a natural evolution of the 2600. Why should you have to spend your CPU's time waiting for each scanline to finish so that you can put new data in it? Internal to the MARIA graphics chip is a pair of linebuffers, and at the beginning of each scanline, it starts calculating the contents of the next scanline. To do that, it uses what Atari called a "Display List", a set of instructions to put what chunks of original memory where into the linebuffer. Unfortunately, the MARIA didn't share the address bus with the CPU (unlike Commodore's VICs), so the more data you wanted it to copy in, the more time it had to steal from the CPU.

This is definitely an oversimplification, but I think it answers the question. The practical limitation for sprites in the 7800 was how much time it took the CPU to set up the display list, and that scaled (superlinearly?) with the number of sprites. So games involving a few very large sprites were comparatively easy.

[OneCrudeDude]

I did some reading myself on that wiki since you linked it.

To go on an alternate history tangent, from the research I made from this thread and others, it seems like the NES would've won over the other consoles even without Nintendo's draconian policies. The console was just more flexible and easier to work with compared to the competition. The SMS would've seen more success since it could handle graphics a little better, but it would've been curtailed by it's relatively inflexible sound processor. Then again, maybe Sega would've released the Yamaha add-on stateside to compete with the NES' audio, which might've pushed Nintendo into 'fixing' the audio expansion and bring a fresh new batch of games over.

Compared to the C64 and the MSX2, the NES has the advantage of being cheaper, though both machines could possibly outdo the NES in power and capabilities, the latter especially. To do that though, it would require more work to accomplish things the NES has for granted, such as scrolling. The C64 is notorious for having obscene loading times, which would further turn down consumers. So in essence, the NES, as flawed as it is, was the most balanced machine.

[tepples]

Compared to the C64 and the MSX2, the NES has the advantage of being cheaper

Was the NES cheaper even after you figure in the cost of games?