CGA/EGA/VGA

If you’re like me and you’ve played a lot of PC games that were released in the late ’80s and early ’90s, you’re probably at least somewhat aware of the different display standards for PC graphics of that era. One thing that was nice about some of these old games was when they allowed you to choose which adapter you wanted to use, since they each had their own color palettes and resolutions. I’m just writing this blog post to cover some of the differences seen in a selection of old DOS games, comparing them and discussing them, and so on. I’m not really going to delve too deeply into the technical details, mainly focusing on the screen outputs, though I will give a basic overview of the capabilities of each display adapter.

CGA

The Color Graphics Adapter debuted in 1981 and was the primary display adapter used in IBM PCs for most of the 1980s. CGA supported two display resolutions and color depths, 320×200 with 4 colors (from a palette of 16) and 640×200 with 2 colors (black and white). There were some other tricks that could be used to squeeze up to 16 colors onto the screen at once, but those weren’t as widely used as the 4 and 2-color modes. For instance, you could use a 160×200 extended graphics mode that let you display 16 colors simultaneously, assuming you were okay with using the ASCII character set to draw everything. There is also a composite CGA mode that you could take advantage of if you happened to have a video card with composite output, and that would allow for the display of 16 colors simultaneously as well, though without the crispness of the more widely used RGB mode. Here’s a nice video explainer of that if you’re interested.

palettecga
The full 16-color CGA palette

Using the 320×200 mode, you had access to two sub-palettes that gave you a selection of these 16 colors that you could apply to individual pixels. Except for the base color (black), you could select a higher-intensity, lighter version of each base color. Keep in mind that you could only display 4 of these colors simultaneously from any given sub-palette using the standard display mode. So if you absolutely needed cyan for that sweet laser sprite, you’d have to choose CGA Palette 1, and you wouldn’t be able to use the green or brown from CGA Palette 0 to draw the grass and dirt under your spaceman hero’s feet.

EGA

In 1984, perhaps after reading the correspondence from developers who agonized over having to choose between cyan and green, IBM released the Enhanced Graphics Adapter for use in IBM and compatible PCs. EGA’s palette included CGA’s palette and its hardware was mostly backwards-compatible with the CGA standard, though there wasn’t 100% compatibility. The EGA graphics modes were 320×200 with 16 colors, 640×200 with 16 colors, 640×350 with 16 colors, and 640×200 with 2 colors, all drawn from a 64-color palette.

paletteega
The 64-color EGA palette (from Wikipedia)

The default EGA 16-color sub-palette was identical to the full CGA palette shown earlier, presumably to aid in backwards-compatibility. But, since you could use all 16 colors simultaneously, you would now be able to have your cool cyan laser beam and your gently waving blades of green grass atop brown dirt. In all seriousness, the difference between 4 and 16 colors is a pretty large chasm that made for a substantial improvement in graphical detail, as you’ll see later on when we get to some screenshots.

VGA

Fast-forwarding to 1987, IBM released its final industry-adopted graphics standard, the Video Graphics Array, or VGA. Nowadays, VGA is probably mainly known for being the type of cable that you plug into your video card to output video to your monitor or other display. VGA was a nice step up from EGA, as it allowed for a 320×200 resolution with 256 colors, 640×480 with 16 colors, 640×350/640×200 in 16 colors or monochrome, and 320×200 with 4 or 16 colors (for compatibility with CGA and EGA, presumably).

While EGA and CGA had fairly fixed primary palettes from which to choose colors, VGA allowed you to use your own 256-color palette, letting you choose from 262,144 possible colors, though there was a default VGA palette that devoted the first 64 colors to the default EGA colors for compatibility.

palettevga
VGA’s default 256-color palette (from Wikipedia)

Thanks to the larger number of possible colors, the level of detail and sophistication of PC graphics expanded pretty dramatically. Also, consider that VGA was marketed in 1987, in an era when the NES (with its 54-color palette) was dominating the home console market. This gave the PC platform a decided advantage over the console world color-wise, until the 16-bit era began in the early ’90s.

Screenshots

This is by no means an exhaustive list. I just fired up DOSBox and did some comparisons between the CGA, EGA, and VGA modes of various games that I stumbled across or whose names made my eyebrows arch. From my delving, I found that there weren’t many games that offered all three as a display option, as most of them either let you choose from CGA/EGA or EGA/VGA. Unless otherwise noted, these will be shown in the order of CGA, EGA, VGA.

Wordtris (1991)

I actually kind of like the EGA title screen more, due to the enhanced contrast.

Mega Man III (1992)

Not a great Mega Man game by any stretch, but the Mega Man character is somewhat suited to CGA’s palette. The EGA mode is definitely a lot easier on the eyes, though, and the enemies don’t blend into the background as they sometimes do using CGA.

Xenon II Megablast (1990)

This is the first game I found that actually used the 640×200 2-color mode. Leave it to the Bitmap Brothers. Unfortunately, the game is very difficult to play in that mode, since it’s hard to discern exactly what is what. Is that round thing that’s slowly coming at me a power-up or an enemy? Hard to tell. I actually think the EGA mode looks superior to the VGA mode, to be honest. The colors contrast a lot more, and the orange really pops out at you in the EGA mode.

Lemmings (1991)

I played this a lot as a kid and, of course, always opted to use the VGA mode, since my Packard Bell 486SX 25 MHz PC gave me access to that power. The CGA mode looks pretty bad, honestly. There isn’t a lot of difference between the EGA and VGA modes, other than some smoother shading in VGA. EGA once again has better contrast. The awesome music is unaffected by your display preferences, however.

Altered Beast (1990)

Believe it or not, Sega released Altered Beast for IBM-compatible PCs around the same time that the Genesis original was sweeping the nation and urging warriors to climb out of their tombs. The CGA mode is actually decently playable, at least on the first level, though when you get into an area with a lot of background details, the playability diminishes quite a bit. There isn’t really much difference at all between the EGA and VGA modes. I’m guessing that might be partially because the Genesis was only capable of displaying 61 simultaneous colors. That’s just speculation, though. The beast transformation screen is still pretty cool regardless of which graphics mode you use.

Civilization (1991)

A stone-cold classic whose VGA graphics I peered at for many hours as a young human being. The EGA mode isn’t really that bad, though the dithering does mar some of the details a little bit.

Commander Keen: Goodbye Galaxy (1991)

The EGA’s expanded palette helps out a lot in this game. I do kind of like the CGA title screen, though, and the dithering/shading on the worm statue is pretty well done.

Paganitzu (1991)

Another solid game from the early days of Apogee. The CGA doesn’t hinder this particular game that much, perhaps because it’s mostly set inside of a catacomb/pyramid. The storyboard graphics look a lot better in EGA, though. That translucent pool of water looks really nice in 16 colors.

Rick Dangerous (1989)

Another Apogee shareware game, Rick Dangerous delivers some solid platforming action. Once again, the CGA works surprisingly well in this one, probably again due to the fact that the action takes place in underground caverns. I’d go with EGA if I were playing it in nowadays, however.

Jill of the Jungle (1992)

Apogee’s fellow shareware pioneers Epic Megagames delivered a string of classic shareware titles in the early ’90s, including Jill of the Jungle. Whenever the [C]GA, [E]GA, [V]GA option came up before the game started, I’d always reflexively hit the V key, so I never knew what the game looked like in non-VGA form. The CGA mode isn’t very appealing, though the CGA mode includes light shading on the text, which EGA and VGA don’t have. VGA mode also includes that snazzy pixelated portrait of Jill, so you know your hardware is being utilized to its fullest whenever you enter a new stage.

Metal Mutant (1991)

I stumbled across this French game while doing research for this blog post. This is the only game I came across that supported both VGA and CGA, but not EGA. That’s a little unusual, and the game is a little unusual also. It might sound weird, but in some ways I preferred the CGA graphics in this game over the VGA. The CGA graphics have better contrast, so you can see more clearly when shots are fired and so on, and the characters stand out more from the background. The title screen even looks cooler to me in CGA, since it evokes that ’80s metallic aesthetic. The robots shown in the cut scenes look good in both CGA and VGA.

Overkill (1992)

I’d forgotten about this game until Todd pointed it out to me. Another classic DOS game from Epic Megagames, this time a space shoot-em-up. The graphics in CGA mode on this one actually aren’t terrible, and the EGA graphics still look pretty crisp and colorful today. The standout feature of this game, though, is the Adlib soundtrack, which is very cool and gets you in the mood to mow down wave after wave of aliens with evil intentions. If you look at the screenshots, you can see that this game actually uses both of the primary CGA palettes, depending on which stage you’re playing – cyan/magenta for the metallic area and brown/green for the organic area. I thought that was a nice touch. Still a pretty fun game to play, even if it’s not as frenzied as some of the more recent bullet-hell shoot-em-ups.

Conclusion

I hope this trek down memory lane was at least somewhat entertaining. Those who also grew up sitting in darkened, EGA-lit rooms might find something to smile about at least. Thanks to Moby Games for the awesome directory that made it a lot easier for me to find some of these examples. Though I made these screenshots myself, you can visit them to find a much larger collection of game knowledge and screen captures.

Until next time.

References

Here are some of the references I used to gather information. If you want more in-depth technical details, you should check these links out.

Wikipedia: CGA, EGA, VGA

Eking 16 colors out of CGA

Information on Color Composite CGA

Very in-depth technical information on CGA

Moby Games’s full list of CGA-compatible DOS games

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