Slope linedef types

Eternity allows you to add slopes to levels, like in ZDoom. They're set up through linedefs, which are activated at level startup.

The slope linedefs work by aligning a sector (front or back) to reach the height of another (back or front) along the linedef.

The floor, the ceiling, or both can be sloped. The various linedefs listed below correspond to the possible combinations.

The slope specials are:

{ 386, "Slope_FrontsectorFloor" },
{ 387, "Slope_FrontsectorCeiling" },
{ 388, "Slope_FrontsectorFloorAndCeiling" },
{ 389, "Slope_BacksectorFloor" },
{ 390, "Slope_BacksectorCeiling" },
{ 391, "Slope_BacksectorFloorAndCeiling" },
{ 392, "Slope_BackFloorAndFrontCeiling" },
{ 393, "Slope_BackCeilingAndFrontFloor" },

{ 394, "Slope_FrontFloorToTaggedSlope" },
{ 395, "Slope_FrontCeilingToTaggedSlope" },
{ 396, "Slope_FrontFloorAndCeilingToTaggedSlope" },

The copy specials do:

394 - Copies the floor slope of a like-tagged sector to the frontsector of the line with the special.

395 - Copies the ceiling slope of a like-tagged sector to the frontsector of the line with the special.

396 - Copies both the floor and ceiling slope of a like-tagged sector to the frontsector of the line with the special.