Class: TMatrix

Inherits:
Matrix
  • Object
show all
Defined in:
lib/transformatrix.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.reflection(lx, ly) ⇒ Object

Create matrix for reflecting about a line interpolating (0,0) and (lx,ly)



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# File 'lib/transformatrix.rb', line 54

def self.reflection lx, ly
  rows [\
    [lx**2-ly**2, 2*lx*ly,    0     ],\
    [2*lx*ly,   ly**2-lx**2, 0     ],\
    [0,       0,       lx**2+ly**2  ]]
end

.rotation(alpha) ⇒ Object

Create matrix for rotating alpha radians about origo



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# File 'lib/transformatrix.rb', line 38

def self.rotation alpha
  rows [ \
    [Math::cos(alpha),  Math::sin(alpha),  0], \
    [-Math::sin(alpha), Math::cos(alpha), 0], \
    [0,         0,          1]]
end

.scaling(sx, sy) ⇒ Object

Create matrix for scaling relative to origo



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# File 'lib/transformatrix.rb', line 62

def self.scaling sx, sy
  rows [\
    [sx,  0, 0],\
    [0,   sy,  0],\
    [0,   0, 1]]
end

.translation(tx, ty) ⇒ Object

Create matrix for translating by [tx, ty]



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# File 'lib/transformatrix.rb', line 46

def self.translation tx, ty
  rows [\
    [1, 0, tx ],\
    [0, 1, ty ],\
    [0, 0, 1  ]]
end

Instance Method Details

#*(arg) ⇒ Object

Multiplication with 2D vector or array



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# File 'lib/transformatrix.rb', line 7

def * arg
  if arg.is_a? Array
    multiply_array arg
  elsif arg.is_a? Vector
    Vector.elements multiply_array(arg.to_a)
  else
    super.* arg
  end
end