The Pedestal Problem
By Jason Harper, JasonHarper@pobox.com
From the "Missed Island" map

If you've ever tried to build a switch, terminal, or recharger that's on a low side (one that you can see over) rather than inset into a solid wall, you may have encountered problems getting them to work. Missed Island has a lot of switches like this, and it about drove me crazy trying to figure out why some worked, and some didn't. I call this the Pedestal Problem (catchy, isn't it).

You just walked past a simple demo of this problem. There are two switches, both controlling the same light. All settings for the two switches are identical. Yet only the left switch works properly: the right one only toggles if punched (or hit with an appropriate weapon).

The only difference between the two switches is the ceiling height...

Here's how I believe things actually work:

Only in the case of toggling a switch via a weapon or punch is its vertical location actually relevant.

For anything controlled by the Action key (switch, terminal, recharger, or door), what matters is the polygon immediately in front of the item. The active area seems to be about 0.5 WU above or below the center of that polygon's height (although I haven't tried to measure it exactly). So, a control panel on a pedestal will only work in areas with a ceiling height not much over 1 WU. In a taller room, the active area of the control panel will actually be up in mid-air over the pedestal!

On Missed Island, the marker switches which respond to the Action key are precisely the ones in areas with a "sky" (ceiling) height of about 1 WU above the ground. Where the sky is higher (due to proximity to a tall building), the switches have to be punched to activate them.

The most annoying instances of the problem are the clock setting switches, and they are also the most impossible instances to fix. The sky there is 4 WU above the ground: if that was reduced by more than 0.5 WU, the top of the clock tower would be clipped when viewed from some locations. That would still leave the active area of the switches about 1.5 WU up in the air. Perhaps in the next version I'll supply you with a 3X recharger (not on a pedestal, of course) and a missile launcher so you can blast yourself up to the proper height.

As far as I know, there's nothing that can be done about this problem other than redesigning the level to have lower ceilings, or using control panels set into walls rather than on pedestals. On Missed Island I couldn't avoid having switches on pedestals, so all I could do about the problem was to write it into the storyline as "sticky switches".

Hopefully this discussion will help some of you to avoid the frustration I went through upon encountering the Pedestal Problem.

(Editors Note: Since this tutorial was written new information has come to light with the release of the source code. In Jason's own words, "The Marathon source code release has made it possible to tell exactly where the active area of a switch or other control panel is, and it turns out that I didn't have it quite right. The active area is vertically centered on a height halfway between the highest floor and lowest ceiling, adjacent to the line on which the control panel is placed. The 'polygon in front of the panel' is of no special significance: that poly generally does have the highest adjacent floor and lowest adjacent ceiling, but one or both heights could just as easily belong to the poly BEHIND the panel." - gls 09/17/2000)

Missed Island