The Grid Wizard is a script that allows you to create a 2D point Master Controller which can be used to position a character rig. For example, you can make a 2D point widget which can be used to rotate your character or their head, change their facial expression, or position one of your character's articulations.
The way this work is by providing the Grid Wizard with a grid of key poses. For example, by providing it with a grid of poses such as the one below, you can generate a 2D point master controller which will make the character look in the point's direction as you move that point around in the Camera view.
The Grid Wizard will generate poses for your Master Controller that interpolate between the poses you feed it. This way, you only have to create poses in key angles (ie: 0°, 45° and 90°) and the Grid Wizard will generate a Master Controller that can pose your character at any angle between those key angles.
To use the Grid Wizard and the Master Controller in this way, the poses you feed it must be interpolatable. This means that they must use the same layers and the same drawings, and that their differences must rely on deformations and geometric transformations.
Once you have fed the Grid Wizard with your poses, it will generate a Master Controller node which will display a 2D point widget in the Camera view. By moving this widget around, the character's pose will change to an intermediary of one of the poses you provided, depending on where the point is moved.
The Grid script works well with 360 rigs, but it can also be used for any purpose where part of a character rig can vary between four or more key poses. For example, you can also use this mechanism to make the character interpolate between four facial expressions.
You can also create a 2D point widget which will control a specific articulation of your character.
You can also use it to create a 2D point to attach a specific articulation of your character to a 2D point widget. In the example below, we position the character's arm based on four different wrist positions, all of which trace a square. Using those four poses, you can create an grid of 2 × 2 poses, allowing you to position the character's wrist, and its whole arm along with it, using a 2D point widget.