See MQPlugin.h about operator overloading in each struct.
typedef struct MQPoint { float x,y,z; } MQPoint;
It indicates a position in a 3D space or a vector.
typedef struct MQPoint2 { float x,y; } MQPoint2;
It indicates a position in a 2D space or a vector.
typedef struct MQColor { float r,g,b; } MQColor;
It indicates a color data consisting of R(red), G(green) and B(blue).
typedef struct MQCoordinate { float u,v; } MQCoordinate;
It indicates a UV coordinate.
typedef struct MQAngle { float head,pich,bank; } MQAngle;
(new in Rev2.30)
It indicates a rotation angle. Each value is from 0 to 360 in degree.
typedef struct MQSelectVertex { int object; //index of object int vertex; //index of vertex } MQSelectVertex;
It indicates a selected vertex.
typedef struct MQSelectLine { int object; //index of object int face; //index of face int line; //index of line } MQSelectLine;
It indicates a selected line.
typedef struct MQSelectFace { int object; //index of object int face; //face of index } MQSelectFace;
It indicates a selected face.