Returns an effect which assigns an aim parameter (most easily created by build-aim-param) to all moving heads of the fixtures supplied when invoked. The direction is a point in the frame of reference of the show, so standing in the audience facing the show, x increases to the left, y away from the ground, and z towards the audience, and the origin is the center of the show. If a pan-tilt-effect or direction-effect is simultaneously running on the same fixture, this effect will win and override whatever the other effect was trying to do, because this one runs later.

Given a head and DMX pan and tilt values, calculate a transformation that represents the current orientation of the head as compared to the default orientation of facing directly towards the positive Z axis.

Determine the default aiming vector for a head, in other words the direction it aims when sent zero values for its DMX pan and tilt channels.

Returns an effect which assigns a direction parameter (most easily created by build-direction-param) to all moving heads of the fixtures supplied when invoked. The direction is a vector in the frame of reference of the show, so standing in the audience facing the show, x increases to the left, y away from the ground, and z towards the audience. If an aim-effect is simultaneously running on the same fixture, it will win and override whatever this effect was trying to do, because it runs later. However, if a pan-tilt-effect is running, it will run before this one, so this one will win.

Returns all heads of the supplied fixtures which are capable of movement, in other words they have either a pan or tilt channel.

Returns an effect which assigns a pan/tilt parameter (most easily created by build-pan-tilt-param) to all moving heads of the fixtures supplied when invoked. The pan and tilt values represent angles in the frame of reference of the show, telling how far the head should move away from facing directly along the z axis. (see show space for a diagram of the axes).

If a direction-effect or aim-effect is simultaneously running on the same fixture, they will win and override whatever this effect was trying to do, because they run later.

If you simply want to set the pan or tilt channels of some fixtures to specific values, without regard to the orientation at which the fixture was hung with respect to show space, you want to use a lower level function-effect with the :pan or :tilt keyword, rather than this effect.