PC Engine color use

[Black Tiger]

OK, so I suspect this post may raise a few hackles, but what the heck, here I go! One of the things our community uses to lord over the MD is the PCE's high on-screen color count. Problem is, a lot of early games didn't make good use of colors. Later CD titles and a few HuCard titles did bust out some nice color use, but I suspect even some of our favorite titles don't really push the color counts. Compare to the Genesis which has actually done some pretty darn impressive things with quite limited color capabilities. Is this related to memory limitations? Is this a lack of artistic vision? What's going on?

It's not overall/total on-screen color counts that make good graphics, it's uncompromised color usage throughout. The Genesis' color limitation isn't the total number of colors onscreen, it's the number of palettes. If the Genesis could use its 512 color master palette however a developer wanted, up to 63 colors total per screen, the games could look as good as or better than the most technically colorful SNES and PCE games.

The SNES can do somethings better better than PCE because of its master palette. Subtle shading for clouds or spamming those non-art filler gradients. SFII eats up half of the Genesis' onscreen color just for the two player sprites. The variety and concentration of detail in the art of the backgrounds requires quite a bit of color flexibilty to recreate the arcade look. Otherwise you wind up with something overly tiled heading towards the SMS SFII look. I doubt that any published games ever pushed even half the availble palettes available fof PCE sprites.

The Sonic games look as good as they do because the were painstakingly designed around the Genesis' color capabilities and look more colorful that games with a similar number of colors. Many SNES games abuse subtle shades and similar colors to create games that don't look very colorful, yet technically have a huge number of colors on-screen.

[spenoza]

I think you've stumbled on something. A lot of game designers on the MD made very careful use of color. There are a ton of MD games that look fantastic because of well-chosen colors and good art design. There are a ton of PCE games which, sadly, look like crap because color use was poor. I think a lot of PCE devs really dropped the ball on properly taking advantage of the PCE's color capabilities.

[Necromancer]

There are a ton of MD games that look fantastic because of well-chosen colors and good art design. There are a ton of PCE games which, sadly, look like crap because color use was poor.

Does not compute.  There's easily just as many nicely colored PCE games as there are on the MD.

[Arkhan]

Super Hydlide made excellent use of the Genesis.

[RegalSin]

You know what I said. Early PCE games that was released were arcade ports. Arcade games have limited colors to begin with. The Genesis was made to mimic it's arcade hardware. The SNES was not. Early arcade machines was limited in colors they could use, not like windows running in 16-bit mode.

Was the Genesis a true 16-bit machine?
The SNES is really an Amiga inside.

The PCE was also a first time project, and because of porting, the usage of code made it easier. Also the concept behind the code ( in terms of colors ) was probably not there as well. However that answer is not clear, because we need to go back in time and see how coders was doing their coding, versus the artist who worked on the images.

Another thing you might not know, some PCE games cheated with coloring, to give it the appearance of having more colors then usually.

[Necromancer]

Hahahahaha!  Just when I think I've read the dumbest thing ever, along comes RegalSin to lower the bar yet again.

[Bonknuts]

As for the A/V and RF output quality of both machines, I really don't know anything about that.  Didn't the Genesis have some infamously bad chroma encoder or something like that?

 
 Heh, yeah. Genesis has crappy color encoding (no alternating phase shift what-so-ever. Not even every other line). But the PCE's composite video is pretty interesting. It's not like the Genesis, where the encoder is stock/off the shelf and external. The VCE chip on the PCE actually makes the outputs needed for composite: four component outputs mixed and amp'd makes the composite video. But what's really interesting is the look up table ROM in the VCE that converts the RGB to YUV on the fly. The VCE has three 3bit R/G/B DACs, but it also has three 5bit YUV DACs (well Y, R-Y, B-Y). So the color conversion is done in the digital domain. The VCE's composite DACs are capable of outputting 32k colors directly (in YUV space), but since they opted to for the realtime conversion table - you can't access any of those other colors. Ok well, that sounds like useless info... but there's a catch. 32k colors in YUV space isn't enough to do a proper conversion from even something as small as 9bit RGB. You need much more accuracy for that kind of conversion. Technically, IIRC, more like 10bit(30bit) per Y/U/V element for 8bit(24bit) R/G/B element conversion. So, you end up with rounding errors. These errors give the PCE's 9bit RGB palette a biased range in the composite output (dunno about RF output because I never looked where it taps the VCE video; composite or RGB). The bias is both in color/hue and brightness. Some games color choices look better under composite (some blues and purples blend better, and some darker colors near grey blend better with grey - than they do in raw 9bit RGB). I mean, it's not a huge difference but it's noticeable once you know what you're looking for. Strider for instance, looks better with the composite altered palette vs raw RGB. Startling Odyssey 2 as well. A few other that I don't recall off the top of my head.

Check 'em out:
http://www.pcedev.net/pics/composite_rgb/pce/PCE_composite_rgb_scale.png
http://www.pcedev.net/pics/composite_rgb/pce/RGB_cc.png

 Anyway, I figured you being an artist guy and all would get a kick out of that

On a side note, i think NEC foresaw the need for a lot of palettes in doing arcade conversions with only one background layer on the PCE.  If you simply paste one parallax layer on top of another and have them scroll as one single layer, you'll need at least one palette for both layers, plus several palettes for where the two layers meet up.  Makes sense to me, as an artist anyway.

 I remember working on SF2 backgrounds with you. Those modifications sure did tear through that BG subpalette amount. Probably would have saved a good amount with two bg layer capability instead.