Rocket launcher

The rocket launcher is used to fire rockets, missles that fly in a straight line and explode when they hit anything solid. When picked up, the launcher contains two rockets (four at the I'm Too Young To Die skill level).

The launcher first appears in a secret area of the level E1M3: Toxin Refinery and appears again in secret areas of the following three levels. It finally appears in a non-secret area in E1M7: Computer Station. It can be put to unusual use in the level E3M6: Mt. Erebus.

In addition to inflicting hit damage (when an enemy is directly hit), a rocket usually inflicts blast damage in the area surrounding its explosion (within a radius of 128 units). Because of this, players firing the rocket launcher will be damaged if they are too close to an explosion.

An enemy that is hit will receive the full 128 hit points of blast damage (unless it is immune, see below), because it is at a distance of zero from the blast. Counting both the hit and the blast, the weapon averages about the same damage as the super shotgun at close range (about three times the regular shotgun), but is equally effective at long range.

Cyberdemons and Spider Masterminds take only the hit damage, and are immune to all blast damage. Therefore, a greater number of rockets is required to kill these bosses than might be expected.

The doom engine uses the same code for exploding rocket blast damage as for exploding barrels, and even the same sound effect. The blast radius is 128 units, and all objects within that radius are examined. For each object that can be damaged, the distance to the exploding rocket is calculated as the greater of the x-distance and the y-distance of the centers, less the radius of the object. The line-of-sight is checked, and if the view of the object from the rocket is obstructed, no damage is inflicted. Otherwise, damage is equal to 128 hit points less the distance.