Beginner’s guide to early 3D computer graphics

Starting in the early and mid 90’s computer graphics were increasingly utilizing 3D. This move to 3D was creating brilliant 3D polygonal worlds and pushing PC gaming (as well as console gaming particularly with the release of systems like the PlayStation) into 3D. Unfortunately this shift was also causing a strain on the CPU’s of the day and their ability to process the massive amount of extra data needed to render graphics in three dimensions. What followed was a massive flood of 3D accelerator cards for the consumer PC gaming market along several different methods of interpreting and then rendering those 3D commands. This article is an attempt to help inform and clear up some possible confusion associated with someone just getting into the world of early and mid 90’s 3d PC gaming. I’m not going to go over things in excruciating detail but hopefully just enough to help someone new to the hobby understand and appreciate this interesting time in the evolution of PC gaming. I will however leave some links throughout the article and at the end that will lead to some great and in depth information for those interested in learning more.

What is a 3d Accelerator card?

Before 3d accelerators computers of course outputted graphics to a display. I went over the early graphics standards in an earlier article here. With the early 2D graphics speed or frame rates were less of an issue then say resolutions and available colors. When windows was released there were some cards that included 2D acceleration for using these graphical user interface operating systems allowing users to run windows more smoothly. Then in the early to mid 1990’s 3D graphics really started taking off but the problem was that these 3D images required huge amounts of calculations to be made my the CPU sometimes slowing the system down considerably. Many, if not most games did not require a 3D accelerator and could be played with solely the CPU rendering the 3D, this is known as running the 3D in software mode. Depending on the power of your CPU and how demanding the 3D game is the results would vary. Some particularly demanding games for their time like Quake could become unplayable due to low frame rates if you did not have a more powerful CPU. Also the addition of a 3D accelerator would usually not only speed up the frame rate to acceptable levels but also add many graphical details that were not possible if playing the game solely through software. This is where the idea of having a video card specifically with the function of making these 3D mathematical calculations come into play as illustrated in the poorly done example below.

So the addition of a 3d accelerator card took the massive mathematical burden off the CPU and allowed 3D games to run smoother and look better, sometimes FAR FAR better. Early cards like the 3DFX Voodoo 1 and 2 used a pass through type connection meaning that they ONLY did 3D and a second video card was required to render 2D graphics.

This method could be an advantage sometimes as you could pair the 3D card up with a very high quality 2D dedicated card but the downside was that there was not only slight signal loss from the need of a extra cable but you also had to sacrifice two expansions slots as opposed to one. This was not the path the industry would take however and with the exception of the first two Voodoo card versions and possibly a rare few other cards the industry turned to all-in-one 2D/3D cards. These cards had the benefit of performing all your graphical needs in one card. Unfortunately many early cards suffered from being a jack of all trades and master of none, having either poor 2D capabilities or in some cases like Matrox’s cards great 2D and lack luster 3D. Now understanding what a 3D accelerator card does I have to talk about API’s or “application programming interface”.

API’s

An API by definition as applied to a 3D video card is “a set of routines, protocols and tools for building software applications.” Basically as best as I can put it an API is a way that allowed the video card to interact with the host computer and render the 3D graphics. This way instead of having to write a program for every single specific brand and revision of graphics card made you can use a general API that allows many different cards from many different manufactures to interact and function on many different computer systems. These days when you go to buy a new graphics card the API isn’t such a huge consideration since the market largely consolidated in the early 2000’s but back in 1995 there was a huge amount of competing cards and API’s. Two of the early API’s and also the only two still used today are Microsoft’s Direct3d and OpenGL. Direct3d is at the time of my writing this up to version 11 with OpenGL being its direct competitor. Generally speaking in 2014 most games (or all as far as I know) can utilize both standards fine but back in the 90’s it was a crap shoot for your 3D card. Most cards could at least take advantage of one standard or the other or sometimes both. Some cards did one better then the other depending on the software drivers that were released. Add to this that many Graphics card manufacturers developed their own proprietary API that only their own brand of card could use and you ended up with some consumer confusion, at least to the non computer savoy crowd. I should add that before the early 2000’s there were quite a few proprietary API’s for many card brands. The most successful was 3DFX’s Glide API but S3 had S3D, Matrox had MSI, ATI had CIF and I can go on.

Being a Graphics card manufacturer the idea was pretty clear. You make a 3D accelerator card that can possibly take advantage of OpenGL, D3D or both for general 3D stuff (neither standard was considered great 3D API’s at the time). Then have your card be able to take advantage of its own API that utilized your own cards strengths. Make deals with various game developers to use your specific cards API or even better ONLY use your cards API and voila, PC gamer Joe will buy your card so he can play your special “3D enhanced” version of said game. As I said before though other then  3DFX and the Glide API used with the Voodoo cards most of the other proprietary API’s fell to the wayside by the late 90’s. 3DFX and Glide lived on into the early 2000’s before going bankrupt and being bought up by Nvidia, who way back in the mid 90’s also had a proprietary API called NV1 before focusing on solely OpenGL/D3D compatible cards.

Early 3d acceleration in games

I’m going to throw out some examples I made of the differences between the various 3D cards of the time (mid 90’s) and there API’s. First thing though is I want to make my method clear. I do not own a fancy VGA capture device and as far as I could find there are no screenshot utilities for DOS games (and the games I used as examples were DOS). So I took these images with a digital camera pointed at the screen. That being said despite the distortions that may be caused by such a method I still think the results are very usable and illustrate things very well. Also keep in mind I’m a bit limited by this blog on image size so please click on the individual images if you want to see them larger and in more detail.

In the early/mid 90’s D3D and OpenGL was not the standards they are today for 3D acceleration and most cards as I said supported one or the other or both but really focused on their own special API. Many games didn’t even support 3D acceleration through D3D or OpenGL but had several different executables available for running the game with several different brand cards and their own API. The first example I’m going to show is Extreme Assault for DOS. This game as far as I know only supported the Voodoo 1 card for 3D acceleration (and via patches the later voodoo 2)

Here we have an image from the game running on a Virge card via software mode. so since this game doesn’t use the Virge cards proprietary S3D API the card is merely displaying the game and not accelerating it. All the 3D work is being done by the CPU. All in all it doesn’t look bad. Take note of the blocky ground textures though. Now by leaving the game and clicking on the special 3dfx executable that came with this game you can take advantage of the games 3D accelerated 3dfx Glide version (provided you have a Voodoo card installed).

One thing your can notice immediately is the ground textures look MUCH better. Instead of being all separate blocks they have blended together to make a much more natural looking ground. A lot of the sharp edges of the helicopter have also been smoothed and rounded such as the top of the helicopter where the rotor blades are. There are though some downsides. The overall blurriness of the image is increased and there is also some screen tearing present as you can notice if you look to the lower left side of the image you can see the trail of white dots. This screen tearing also happened when I tried the Voodoo 2 and patched version of this game.

another example from this game.

Again we have blurring to the image destroying most of the fine details on the truck but also making the ground texture look much better. Also take note of the overhang on the building to the left. I think the 3DFX version looks much more natural and rounded.

For the next several examples I’m using the game Tomb Raider since it supports a wide range of proprietary 3d API versions and not OpenGL or D3D. Also I combined these images into more compact images to save space so please remember to click on the images to enlarge if necessary. First off The cards I used for this project. These do not represent all the Proprietary API’s used at the time and a few are missing (Glint, NV1) but I feel I have a majority of popular ones.

First off a quick comparison between software mode and Glide on a 3dfx Voodoo card, the dominant API of the era.

Other then being a little darker in image quality the Glide version blows away the software mode. Laura and the games textures in general just look so much better overall. Colors blend nicely and the jaggyness is really smoothed out.

Next are several comparisons of different parts of the game using all the cards and there respective API’s listed above. software mode is also included as a baseline. Because of the limited horizontal space I have for this blog and images the pictures are kind of small and hard to see the detailed differences, please click them to enlarge.

*** things to note***

1. the purple lines that sometimes appear on the Verite card are possibly caused by an incompatibility with the newer Verite 2100 card I used and this glitch as far as I know does not occur with the original version of the card the Verite 1000
2. The fine line appearing around some objects in the 3dfx glide version will go away by unselecting mipmapping in gfx options. It also does not appear if using a voodoo 2 card and the voodoo rush patch
3. I’ve been told that the ATI version does have shadows and I may of had an issue with my card/drivers. I attempted to use a newer ATI Rage pro card and the correct drivers but got a error on loading the game and just gave it up.

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BONUS

here are some shots taken with the 3dfx Voodoo II patch using 2x 12mb voodoo II cards in SLI. In my opinion the games looks a bit nicer, possibly due to superior filtering in the V2 then on a voodoo 1 and I didn’t have that black line issue I did with the V1

In my own opinion the Power VR, 3DFX and Verite versions look the best of the bunch. The Power VR version may edge out the other slightly and underwater especially looks nice with the Power VR. You will need a beefier CPU to run the PVR version though smoothly. The Matrox version looks a little better then software. also notice the Matrox cards have a problem with the shadows since it has problems with blending and it creates a checkered effect known as stipple alpha (thank you Idspispopd at Vogons). The ATI and Virge versions look very dark in the images and were darker by default but looking at the actual monitor and not a camera image the game wasn’t to dark to play at all.

different options and quirks appeared depending on the card used.

S3 Virge (S3D)

• Image darker overall by default
• Under graphics options “perspective” and “biliner” available
• Resolution adjustable up to max resolution of 640×480

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3DFX Voodoo 1 (Glide)

• 3dfx logo appears on starting game
• Under graphics option you get “mipmapping” and “normal” *selecting mipmapping creates glitches unless using a voodoo 2 and the voodoo rush patch

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Matrox Mystique (MSI)

• Matrox logo screen on starting game, but only if in true DOS mode
• Hardest version for me to get running (had to try several different PC’s and configs before it worked, reason unknown)
• No graphics options at all at menu
• Checkered effect on all shadows and over select screens caused by cards problems with blending

ATI Rage II + DVD (CIF)

• Image darker overall by default
• Under graphics options “perspective” and “biliner” avaliable
• Resolution adjustable up to max resolution of 800×600
• no shadows *only because of an issue with my card/drivers. video of the game running fine on a Rage Pro card here

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Rendition Verite 2100 (Speedy 3d)

• standard graphics options (same as under software)

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PowerVR (PowerSGL)

• no options under “graphics” just says “N/A”

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And finally from Tomb Raider an image of the swimming pool from each card. notice how every card renders the water color differently.

Lastly before I Wrap this one up some images from Quake. Other then its software mode Quake supports 3D acceleration via Glide and OpenGL but the images I have here are just comparing software mode to Vquake aka the Verite speedy3D accelerated version. The Verite card enhanced version of Quake was the first 3d accelerated version. It lacks some features that other accelerated versions possess such as its inability to display transparent water surfaces but it is the only version that supports anti-aliasing which is a graphical process that sharpens jaggy lines. Notice the gun barrel looks subtly better in the accelerated version.

Here is a good example of the benefits of 3d acceleration. The enemy soldier looks far better textured in the Verite version. Especially notice the head.

By the late 90’s most of the proprietary API’s were gone and today D3D and OpenGL rule the roost. API’s and their exclusivity is no longer a concern for potential graphics card buyers (though I hear rumors of AMD creating its own for its Radeon gfx card line). When building a retro PC for the mid 90’s era the selection and various merits and faults of 3D cards can be confusing but hopefully this article gave you a better overall understanding of the concept. Before wrapping it up I’m leaving a few links to some very good and details sources on early 3D cards.

Mechwarrior 2 card compairison video – an awesome video displaying the difference between 5 different accelerated versions of mechwarrior 2. he also has many other 3d comparison videos available.

Vintage 3d – early history of 3d acceleration  – A great site with reviews, comparisons and technical details on a huge range of early 3d cards

3D Rage – page on the ATI 3d Rage cards and differences