the data passed into glm::lookAt()
can construct some useful vectors for viewing.
- The viewVector = viewPoint – eyePoint
- The strafeVector = viewVector x
- The orthogonal upVector = strafeVector x viewVector. This may be needed if the upVector is not
orthogonal to the viewVector.
Typically, one normalises these
the camera along the
- viewVector makes the camera move
- strafeVector makes the camera move
- orthogonal upVector makes the camera move