Serious Engine 1 is the first engine developed by Croteam, and was originally designed for Serious Sam: The First Encounter. The goal behind the engine was so that a large amount of polygons and enemies can be rendered on-screen with “modern” special effects like realistic shadows and lighting effects without causing none or very little slowdown.
Besides the PC, the Serious Engine 1 was also programmed to work on the Xbox, as seen in Serious Sam: Xbox.
Serious Engine 1 uses Serious Editor 1 and the tools associated with it in order to create and edit content. Serious Engine 1 is used to create levels and textures, while a complementary tool, Serious Moddler, allowed them to import models from programs like 3DS Max to the Serious Engine .mdl format.
Serious Engine 1 boast several features that made it unique among engines at the time:
- Support for very long distances.
- Support for high-quality terrain models, which can be used in levels.
- Colored lighting that can blink or do other effects without any problems.
- Portals that let someone look at another part of the level through a mirror.
- Sunglares to make levels look more realistic.
- Levels do not need to be complied in order to test a level. Real-time calculations keep the level up to date while it's being worked on. This lets someone playtest levels straight from the editor.
- Fog and Haze.
- Support for unusual gravity, which lets the player do things like walk on walls.
- Real time shadows that work with many characters on screen.
- Support for several popular graphic card series at the time, like the Voodoo 3.
Originally, the engine supported normal maps (textures that give the illusion of a model having more polygons and more details than it really does). This can be seen in Test 1's Technology Test level. However, by the final version of Serious Sam: The First Encounter, this feature appears to be broken, as it doesn't render properly in the Technology Test level.
Serious Engine 1 began life as the S-Scape 3D engine, which was going to be used in In the Flesh, an early version of Serious Sam: The First Encounter. According to a page about it written in 1996, the engine was to feature things such as support for bit color depths up to 16 million, advanced special effects like reflections and realistic shadows, and it's own scripting language for creating events in levels. This would've been quite impressive for late 1997, it's original release date, if they managed to reach most of these goals.
It's likely that the S-Cape 3D engine was renamed to Serious Engine (1) because In the Flesh was renamed to Serious Sam and that a new name would help tie it to Serious Sam.