ppModeler uses 3D and 2D manipulators to provide an easy access to the moving, rotating and scaling
functionality of the selected groups.
The manipulator can be hided/shown with the space bar.
A manipulator can have 5 types of handles:
: the move handle;
: the rotate handle;
: the scale handle;
: the uniform scale handle;
: the move center of rotation/scale handle.
Each manipulator's handle is colored by the following rule:
RED for the X axis constaint
(move along X axis, scale along X axis, rotate around X axis);
GREEN for the Y axis constaint;
BLUE for the Z axis constaint;
WHITE for no constraint (move freely, scale freely, scale uniformly, rotate around the view axis).
For example, this is the 3D manipulator for meshes, faces, edges and group of vertices:

And the 2D manipulator, for uv coordinates and 2D curves:

In the menu 'Options->Cfg...', the rotation circles and the axis of the 3D and 2D manipulator can be disabled or drawn dotted.
This helps to clean up the working area when the user is used to the manipulator: