Method: PerfectShape::AffineTransform#initialize

Defined in:
lib/perfect_shape/affine_transform.rb

#initialize(xxp_element = nil, xyp_element = nil, yxp_element = nil, yyp_element = nil, xt_element = nil, yt_element = nil, xxp: nil, xyp: nil, yxp: nil, yyp: nil, xt: nil, yt: nil, m11: nil, m12: nil, m21: nil, m22: nil, m13: nil, m23: nil) ⇒ AffineTransform

Creates a new AffineTransform with the following Matrix:

xxp xyp xt
yxp yyp yt

The Matrix is used to transform (x,y) point coordinates as follows:

xxp xyp xt
  • x

    [ xxp * x + xyp * y + xt ]

yxp yyp yt
  • y

    [ yxp * x + yyp * y + yt ]

xxp is the x coordinate x product (m11) xyp is the x coordinate y product (m12) yxp is the y coordinate x product (m21) yyp is the y coordinate y product (m22) xt is the x coordinate translation (m13) yt is the y coordinate translation (m23)

The constructor accepts either the (x,y)-operation related argument/kwarg names or traditional Matrix element kwarg names

Example with (x,y)-operation kwarg names:

AffineTransform.new(xxp: 2, xyp: 3, yxp: 4, yyp: 5, xt: 6, yt: 7)

Example with traditional Matrix element kwarg names:

AffineTransform.new(m11: 2, m12: 3, m21: 4, m22: 5, m13: 6, m23: 7)

Example with standard arguments:

AffineTransform.new(2, 3, 4, 5, 6, 7)

If no arguments are supplied, it constructs an identity matrix (i.e. like calling ‘::new(xxp: 1, xyp: 0, yxp: 0, yyp: 1, xt: 0, yt: 0)`)



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# File 'lib/perfect_shape/affine_transform.rb', line 74

def initialize(xxp_element = nil, xyp_element = nil, yxp_element = nil, yyp_element = nil, xt_element = nil, yt_element = nil,
               xxp: nil, xyp: nil, yxp: nil, yyp: nil, xt: nil, yt: nil,
               m11: nil, m12: nil, m21: nil, m22: nil, m13: nil, m23: nil)
  self.xxp = xxp_element || xxp || m11 || 1
  self.xyp = xyp_element || xyp || m12 || 0
  self.yxp = yxp_element || yxp || m21 || 0
  self.yyp = yyp_element || yyp || m22 || 1
  self.xt  = xt_element  || xt  || m13 || 0
  self.yt  = yt_element  || yt  || m23 || 0
end