Linedef type 417
The high and low light settings of the light pulse are determined by the light levels in the control sector and the target sector. It doesn't matter which one is brighter. The control linedef's length determines the speed of the pulsating light, in relation to the two brightnesses specified. Four fracunits of length mean that the light level will change by one unit per tic, so the longer the linedef, the quicker the speed. Normal speed is 32 fracunits (or 8 units of light level per tic). The two brightness levels are also a factor in how quickly the light pulsates. For example, even if the speed for both cases has the same value, a case where the brightness levels don't differ by much will still pulsate quicker than another case where the brightness levels differ by a lot.
If you use a two-sided linedef with the Not Climbable flag checked, the light level of the linedef's back sector will be used as the second light level, instead of the target sector, allowing you to set the latter at a different starting light level entirely.
In the Software renderer, the brightness levels can also determine how smoothly the light pulsates. Also note that, since the Software renderer only has 32 distinct light levels, the pulsating effect may not be visible if the chosen light levels are too close together.
- Example WAD: ex_ld417_startadjustableglowinglight.wad
- This example WAD can be played in any gametype. It uses
MAP01, replacing Greenflower Zone Act 1.