Doom Wiki


3,599pages on
this wiki
Add New Page
Talk0 Share

Slopes are an editing feature supported by some Doom source ports which allows the designer to make surfaces that are at angles other than horizontal or vertical. Sloped surfaces in a 2.5D system have issues that are mostly irrelevant in true 3D engines such as Quake.

In a 2.5D map system, depending on the implementation, it can be either floors or walls that are sloped. Doom source ports usually prefer to slope the floors and ceilings, just like, for example, Duke Nukem 3D, as it is technically more efficient[1]. Regardless of the implementation, the greater the angle between the surface and its "normal" (horizontal or vertical) alignment, the more stretched its texture. Source ports may provide mechanisms to alleviate the problem, such as the Sector_Set*Scale specials in ZDoom.

A full implementation of sloped surfaces includes changes to both the renderer and the physics code. The former is relatively simpler than the latter, since even slight changes in the physics code risk breaking demo compatibility.

Ports with slopes

External links


  1. Ken Silverman interview: "It could have been a bit faster if I had rendered them as horizontal lines instead of vertical."

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.