SCALING
Scaling is a kind of transformation in which the size of an object is changed. Remember the change is
size does no mean any change in shape. This kind of transformation can be
carried out for polygons by multiplying each coordinate of the polygon by the
scaling factor.
Sx
and Sy
which in turn produces new
coordinate of
(x,y) as
(x',y'). The equation would
look like
or
here
S
represents the scaling
matrix.
NOTE: If the values of scaling factor are greater than 1 then
the object is enlarged and if it is less that 1 it reduces the size of the
object. Keeping value as 1 does not changes the object.
Uniform Scaling: To achieve uniform scaling the values of scaling factor must be kept equal.
Differential Scaling: Unequal or Differential scaling is produce incases when values for scaling factor are not equal.
As per usual phenomenon of scaling an object moves closer to origin when the values of scaling factor are less than 1. To prevent object from moving or changing its position while is scaling we can use a point that is would be fixed to its position while scaling which is commonly referred as fixed point (xf yf).