Both subroutines create a matrix and premultiply it into the current matrix. The translate subroutine moves the object origin to the point specified in the current object coordinate system. All objects drawn after the translate subroutine executes are translated. The translate subroutine creates a matrix and premultiplies it into the current matrix. The scale subroutine shrinks, expands, and mirrors objects.
Negative values cause mirroring.
All objects that are drawn after the scale subroutine executes are scaled. The scale subroutine creates a matrix and premultiplies it into the current matrix. The modeling subroutines are illustrated in the following figure . Rotations are about the origin of the coordinate system. The viewing transformations allow you to specify the position of the eye in the world coordinate system, and to specify the direction toward which it is looking.