I’ve read that enemies in Doom are rendered as sprites because of hardware limitations. But why is it that walls, stairs, etc. appear fully 3d by contrast?
[example](https://www.youtube.com/watch?v=tDmf9dgso84)
​
In: Technology
Doom was written for a time when the average hardware was a low-end 486 or a high-end 386. You could not rely on the CPU supporting floating point instructions, and if they did it would be slow. 3d accelerator cards wouldn’t be in the hands of the general public for around 5 years or so. Having a 66 MHz CPU meant the game would run REALLY well.
The graphics engine really cheated by having limits on the terrain. This meant it could make assumptions that wouldn’t be valid for real 3d rendering, but a hacky way of doing the graphics would be fast and look good enough under these limits. Rooms look 3d, but you could only have staircases, no ramps. Rooms could not be placed above/below each other. The way the drawing worked was based on columns, knowing that each surface being drawn was either a vertical wall or a flat floor/ceiling.
This meant that all the rest of the things were just drawn as sprites. The game was not really 3d, and a “model” for a 3d thing didn’t exist. Enemies and things were just drawn, scaled based on distance, with their position on the floor as a reference for where to draw it.
Latest Answers