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sony trinitron + color emphasis bits = scrambled image?

sony trinitron + color emphasis bits = scrambled image?
by on (#90009)
Recently I decided to dim the screen when you hit "pause," in Nomolos. I used all three color emphasis bits. Works great in emulators, looks fine on a little 13 inch TV I have, but on my Sony Trinitron, it causes an extremely ugly bunch of scanline artifacts. I tried mucking with the settings on the TV, to no avail. Has anyone else seen this sort of thing on a crt tv, in a game that uses color emphasis?

I decided to use the monochrome bit instead for the pause screen, but it would have been slick to dim the screen with color emphasis.

by on (#90012)
Then perhaps the warning in some older documents against using more than one emphasis bit wasn't full of crap. RGB units (Famicom Titler, PlayChoice, some TVs with a built-in Famicom) don't take very well to multiple emphasis bits turned on either.

What you can do to simulate the old effect is dim all elements of the palette by subtracting $10.

by on (#90013)
I have an ancient Trinitron that's older than I am, and Battle Kid's pause effect works fine.

by on (#90014)
Don't some other games do this? I have a Sony Trinitron too and never saw anything like this.

by on (#90015)
If all preemphasis bits are set, then color 1D ("black") becomes blacker-than-black and 01-0C no longer decode to a valid RGB color from the received YIQ values (Their brightness is approximately equal to unattenuated color 1D). So if it looks like scanlines restarting all over the place, maybe that's why?

by on (#90018)
The game Just Breed have all the emphasis bits set (most of the time, I think sometimes during lightning effects the game might briefly clear them).
Noah's Ark it like that too if I remember.

by on (#90024)
Many clones also do not support the emphasis bits, if that is something you care about.

by on (#90025)
Using the emphasis bits is the lazy mans way of dimming the screen IMO. Plus, good luck porting your game to any RGB NES arcade system. (Which I want to do one day, sue me.)

by on (#90026)
If it's not much trouble, maybe you could post the palette values you're using when that happens. But I guess it's specific to your TV, or some certain TV types.

I believe Super Spy Hunter sets all emphasis bits when you pause it. Munchie Attack does it when you lose all your lives (and yeah it didn't look too hot on the Playchoice, everything goes grey).

by on (#90032)
bunnyboy wrote:
Many clones also do not support the emphasis bits, if that is something you care about.

Really? I didn't know about that. I guess I'll have to test my clones!

by on (#90039)
Yep, I see some bending myself in one of the palette demos (pal test) on my Trinitron.

Try using $3f for black instead of $0d if possible and see if it helps any.

by on (#90046)
tokumaru wrote:
bunnyboy wrote:
Many clones also do not support the emphasis bits, if that is something you care about.

Really? I didn't know about that. I guess I'll have to test my clones!

I noticed it in one of Sivaks early games, so it was probably one of Yobo/NEX/RetroDuo. The 3 system clones weren't out yet.

by on (#90051)
They don't support it in what way? Simply not working or don't give expected behavior?
Re: sony trinitron + color emphasis bits = scrambled image?
by on (#90084)
Gradualore wrote:
I decided to use the monochrome bit instead for the pause screen, but it would have been slick to dim the screen with color emphasis.

Why not dim it by rewriting the palette instead?

by on (#90085)
3gengames wrote:
Plus, good luck porting your game to any RGB NES arcade system. (Which I want to do one day, sue me.)

Screen turning white when pausing the game hardly is game breaking behavior. Of course if the emphasis bits are used for other purposes (like keeping the palette dimmed all the time, like in Jungle Book, James Bond Jr and Felix the Cat), it's an entirely different deal.

by on (#90126)
So is it safe to say that using the emphasis bits is back in the "don't use" box due to possible problems on some tvs?

by on (#90133)
No, a lot of licenced games uses them, including some who has the bits constantly set so I don't think one should avoid to use them just because the RGB PPUs, which are about 0.002% of the NES-compatible machines arround the world, doesn't support them (come one who has arcade machines in his living room ?).

When it comes to clones it's more ambiguous. Clones probably represent at least 50% if not more than NES-compatible machines around the world, but they are clones and will remain that way. If you want to design your games for clones, then yeah don't use the emphasis bits, but most people there target the "real thing" instead.

by on (#90134)
Lots of people who buy repros though have modded systems, so there may be a lot more NES's, but I'd be a lot higher ammount of PPU use RGB NES's then you'd think. And clones too are out there too. I myself don't see a whole lot you can gain except for being incompatible with some real hardware because you wanted to hack something in rather then use the palette.

by on (#90141)
From all my experience, clones just darken a bit too much with the emphasis bits compared to the real NES. For example, with all bits on, the NES would be at 80% brightness or so, and clones at 65% or 70%.

That's all, just a stronger effect. Not a game-ruiner like the RGB PPU.

by on (#90143)
Considering how limited as the NES palette is in hues/luminances, I very see valid reasons for using the emphasis bits to adjust it slightly for your game's color design, if you really want to make your game look as good as possible.

Than again, for the sorry people who only have clones, it could be good to include a clone detection routine (trying out lots of the weird side-effects of the NES hardware that very few clones should support) and disabling their use in this case. And/or provide a menu to toggle their use on/off.

by on (#90225)
Wouldn't it stil be a good idea to not use it wherever possible though? Just in case a particular tv doesn't like it. (good example is battlekid...who only uses it for pausing...same could be acomplished with palette darkening)

by on (#90226)
The problem is, subtracting the palette values by $10 darks the palette to much imo. It looks okay, if you just want to fade out the screen (for example on game over), but not for pause, because it looks to abrupt.

by on (#90227)
Point is, they can make your game look better. Or at least look more like you would imagine it.

For example, the color palette of the NES has an extreme amount of greenish hues, less of blueish ones, and virtually no good reds/browns. So if you want for example to make your brown look less greenish, you could set the red and blue emphasis to compensate.

Of course, it'll also look different on NTSC or PAL, and might even look slighltly different on different TV sets. So ultimately, adjusting for "the best experience" will only be 100% successful in your home TV room. But since you're probably playing around with this ancient hardware for personal reasons anyway, I guess that's the best measure you can have... :P

But even ignoring composite/RGB differences, don't forget this when becoming too obsessed with finding the "right" color.

by on (#90556)
Thanks for your responses. I replaced all usage of $0d with $0e and the artifacts went away. Using the emphasis bits for pause sure looks slick, but I decided to go with the monochrome bit instead. I'd like to be able to run on clones with few issues. Maybe in a future game I can have an option screen that can turn emphasis bit usage on or off so people with original hardware can get richer colors.

by on (#90559)
How about instad of the monochrome bit, upload a 4 grey color palette. Just because the outlines will then be seeable, as there's actually 2 whites in the monochrome mode. :)

ETA: I don't know why, but I thought 0F was the color black that should be used. At least that's what everyone else uses.

by on (#90566)
Jeroen wrote:
Wouldn't it stil be a good idea to not use it wherever possible though? Just in case a particular tv doesn't like it. (good example is battlekid...who only uses it for pausing...same could be acomplished with palette darkening)

I don't think we should worry about this too much.

A similar argument to this would be to avoid the 25% and 50% squares for compatibility with clones. It's just a huge tradeoff for not enough of a gain.

by on (#90569)
But darkening the palette isn't a loss, it's just a lazy way of darkening it. And besides, clones aren't official hardware while RGB chips are.

by on (#90590)
It's not a lazy way of darkening it any more than using the sprite DMA is a lazy way of updating your sprites.

If it becomes an astoundingly terrible problem for RGB NESes, then we can release a special RGB version of our homebrew games, much like we would likely already be needing to do with PAL/NTSC.

by on (#90591)
That's the thing, write your game right and use programming to get around those hardware mismatches beforehand and you don't have to worry about RGB systems at all.
If it's not a ThinkPad, it's a clone
by on (#90602)
3gengames wrote:
And besides, clones aren't official hardware while RGB chips are.

Lenovo PCs have an unbroken legacy back to IBM's original PC; everybody else's PCs are clones. But by now, PC clones far outnumber Lenovo PCs. Right now I'm typing this comment into a clone made by Dell. The same will gradually become true of the NES as Nintendo consoles get thrown out (by mistake, by people who no longer game and aren't aware of eBay, and people who don't know how to replace a 72 pin connector).

by on (#90606)
I bet that even NES clones will be extinct soon, unless someone in the retro gaming community decides to manufacture clones and sell them. I don't know, I don't see this over-abused 8-bit technology being commercially interesting much longer.

by on (#90643)
Quote:
Lenovo PCs have an unbroken legacy back to IBM's original PC; everybody else's PCs are clones. But by now, PC clones far outnumber Lenovo PCs.

Whoooho this means my PC is not a "clone".

That being said it's still VERY MUCH different from the start of the PC standard in the 80s, and much more similar to a modern PC from another copany.

On the other hand NESes can't be upgraded (OK one could put some 8k RAM instead of 2k, then what ?) and Nintendo stopping producing them so the comparison doesn't make any sense.

by on (#90644)
Bregalad wrote:
On the other hand NESes can't be upgraded

Pirates have made various additions to the PPU, allowing for more colors and sprites.

by on (#90647)
Which ones are those? I always thought it would be kind of interesting if first you had a solid clone, no cart port wiring or duty cycle errors, and then added some extra capability like being able to enable extended features like 8K WRAM, More Sprites, DMA from CPU to PPU, Built in Scanline IRQ, maybe CPU overclocking if it could avoid APU issues.

by on (#90648)
Chips for upgraded Famiclones and other stuff.

by on (#90651)
Take a look at the specifications for one of their consoles and you can see how they upgraded the PPU.

by on (#90690)
That looks interesting. But without taking a standard cartridge (like the PowerPAK) is limits its use. And it would be nice if it were an actual console and not a "TV game" controller all in one thing.

by on (#90702)
I think they offer an emulator and test programs with the new features, so you can try them out a bit.

by on (#90757)
tokumaru wrote:
I bet that even NES clones will be extinct soon
I thought that famiclones where still the primary console in large parts of the world (especially in developing countries). Which means that there's probably a large supply of manufacturers who have no reason to exit the business.

Heck, there's still commercial game development taking place in China. (It's a bit disingenuous to call them "pirates" when they write there own stuff. On the other tentacle, the rest of the game's IP does tend to violate copyrights and trademarks.)

Quote:
unless someone in the retro gaming community decides to manufacture clones and sell them.
I'd say this is a good idea, but probably not cost competitive currently. However, a feature complete open source clone sounds like a worthy endeavor to me.

Edit

Also, the VT(12)68 looks like some pretty cool chips from the specs. They're like a SNES with a 6502. (And they have the coolest postal address ever: "Kung Fu Rd")

MottZilla wrote:
That looks interesting. But without taking a standard cartridge (like the PowerPAK) is limits its use. And it would be nice if it were an actual console and not a "TV game" controller all in one thing.

The company sells chips, not devices. So one could build their own console if they wanted to.

by on (#90775)
Karatorian wrote:
tokumaru wrote:
I bet that even NES clones will be extinct soon
I thought that famiclones where still the primary console in large parts of the world (especially in developing countries). Which means that there's probably a large supply of manufacturers who have no reason to exit the business.


Whoever they are, if they have business good for them. But none of those famiclones are systems that accept NES or Famicom carts, despite being a clone NES system. That means while there may be more clones in other countries, they're NOT NES or Famicom systems, they're an NES core with everything else different.

by on (#90821)
3gengames wrote:
But none of those famiclones are systems that accept NES or Famicom carts, despite being a clone NES system. That means while there may be more clones in other countries, they're NOT NES or Famicom systems, they're an NES core with everything else different.

We must not be thinking of the same systems. I thought that parts of the Middle East (and elsewhere, like India) still had lots of pirated Famicom carts being sold. Presumably one can buy systems also.

Of course, this is all hearsay on my part. I haven't seen it myself. Also things may have changed in the years since the accounts I've read where written.

by on (#90840)
I'll be honest, I get a little depressed when I think about how tilemap-driven VDPs are obsolete.

The only use for them would be for novelty $1 game systems or something.

by on (#90849)
Drag wrote:
I'll be honest, I get a little depressed when I think about how tilemap-driven VDPs are obsolete.

The only use for them would be for novelty $1 game systems or something.


I get the same way but it's more driven by my lack-of-interest in the uber-realism 3D worlds that took over. I don't know if it's age-related...I just have a hard time keeping track of things [where did I leave my horse again, dammit...] Much easier to remember the extra life is in the block next to the third pipe. Also, the early days of 3D were plagued with z-order bugs that just drove me nuts...cameras going behind walls, etc. Perhaps it's better now--or perhaps the number of vertices has approached a limit so visually stunning, and gameplay has become so fast-and-furious that these bugs are less noticed. Or perhaps better algorithms came along.

by on (#90851)
I blame it on the idea that developers don't know what a game is and how it's different from a movie. I also blame it on modern gamers because they'll eat this crap up, which spurs publishers to only want more of it, so developers wind up needing to take the indie approach in order to make something different, where the indie community is also full of novices and generally gets a bad rap for low production values, at least on the 360.

I think gaming (as we knew it, at least) died the moment DLC and achievements became commonplace.

This is also why I tend to stick with Nintendo; they don't do this crap. Sure, they may rerelease 20 year old games over and over, but at least those were good games.

by on (#90852)
cpow wrote:
I don't know if it's age-related...I just have a hard time keeping track of things [where did I leave my horse again, dammit...] Much easier to remember the extra life is in the block next to the third pipe.

And the classic 2D game design paradigms live on in smartphone games. The only difference is that an orientation sensor and multitouch screen with no tactile feedback have replaced the Control Pad and buttons, and developers and players are assumed to be paying $50 per month for a cellular voice and data plan.

Quote:
Also, the early days of 3D were plagued with z-order bugs that just drove me nuts...cameras going behind walls, etc. Perhaps it's better now

Z order was broken on the Jaguar, 3DO, Saturn, and the original PlayStation, which would always sort entire polygons. N64 and every sixth- and seventh-generation console, on the other hand, have a depth buffer or "Z buffer" that in effect sorts individual pixels, fixing the most common Z-order bugs. As for cameras getting stuck behind walls, engine programmers have learned to cheat those angles by manipulating the near clipping plane. Super Mario 64 was over a decade ago, and Nintendo is up to Super Mario 67 now.