RotationMatrixVectorLib

A C++ library for performing seemless math operations on 2D & 3D vectors and calculating rotation matrices used in 3D Cartesian coordinate space.

Things to Know

• Rotation matrices can be used to track the orientation of a mobile rigid-body relative to a world axis reference frame.
• Intrinsic rotations rotate about the axes of the fixed coordinate system frame that's attached to the rigid body in motion.
• The orientation of a frame is itself a rotation matrix.

How To Use This Library

• Matrix multiplication A*B or Multiply(A, B) assumes A is the row matrix while B is the column matrix.
• The *= operator can be used like so: A *= B, means A = A*B, where B is the column matrix.

ROTATIONS:

Z AXIS ROTATION:

Matrix3x3 rotation = Matrix3x3::RotZ(PI/2.0);

EULER ROTATION:

rotation *= (Matrix3x3::RotZ(yaw) * Matrix3x3::RotY(pitch)) * Matrix3x3::RotX(roll);

YAW-PITCH-ROLL:

rotation *= YPR(180PI/180, 45PI/180, 90*PI/180);

Undo rotation:

Matrix3x3 rotation = YPR(180PI/180, 45PI/180, 90*PI/180);

rotation *= RPY(-180PI/180, -45PI/180, -90*PI/180);

VECTORS

Vector3<int> mouse = leftJoystick.Read();

Vector3<float> position = Vector3<float>(0, 29.9, 42);

Vector3<float> gravity = Vector3<float>(0, -9.81, 0);

Vector3<float> velocity; // defaults to zero vector

velocity += gravity;

position += velocity;

gravity *= 100;