Class: Mittsu::Matrix3

Inherits:
Object
  • Object
show all
Defined in:
lib/mittsu/math/matrix3.rb

Constant Summary collapse

DIMENSIONS = 
3

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Matrix3

Returns a new instance of Matrix3.



9
10
11
12
13
14
15
 
# File 'lib/mittsu/math/matrix3.rb', line 9

def initialize()
  @elements = [
    1.0, 0.0, 0.0,
    0.0, 1.0, 0.0,
    0.0, 0.0, 1.0
  ]
end

Instance Attribute Details

#elements ⇒ Object

Returns the value of attribute elements.



5
6
7
 
# File 'lib/mittsu/math/matrix3.rb', line 5

def elements
  @elements
end

Instance Method Details

#==(other) ⇒ Object 



147
148
149
 
# File 'lib/mittsu/math/matrix3.rb', line 147

def ==(other)
  other.elements == @elements
end

#apply_to_vector3_array(array, offset = 0, length = array.length) ⇒ Object 



44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
 
# File 'lib/mittsu/math/matrix3.rb', line 44

def apply_to_vector3_array(array, offset = 0, length = array.length)
  v1 = Mittsu::Vector3.new
  i, j = 0, offset
  while i < length
    v1.x = array[j]
    v1.y = array[j + 1]
    v1.z = array[j + 2]
    v1.apply_matrix3(self)
    array[j]     = v1.x
    array[j + 1] = v1.y
    array[j + 2] = v1.z
    i += 3
    j += 3
  end
  array
end

#clone ⇒ Object 



165
166
167
 
# File 'lib/mittsu/math/matrix3.rb', line 165

def clone
  Mittsu::Matrix3.new.from_array(self.elements)
end

#copy(m) ⇒ Object 



34
35
36
37
38
39
40
41
42
 
# File 'lib/mittsu/math/matrix3.rb', line 34

def copy(m)
  me = m.elements
  self.set(
    me[0], me[3], me[6],
    me[1], me[4], me[7],
    me[2], me[5], me[8]
  )
  self
end

#determinant ⇒ Object 



69
70
71
72
 
# File 'lib/mittsu/math/matrix3.rb', line 69

def determinant
  a, b, c, d, e, f, g, h, i = *self.elements
  a * e * i - a * f * h - b * d * i + b * f * g + c * d * h - c * e * g
end

#flatten_to_array_offset(array, offset) ⇒ Object 



113
114
115
116
117
118
119
120
121
122
123
124
125
 
# File 'lib/mittsu/math/matrix3.rb', line 113

def flatten_to_array_offset(array, offset)
  te = self.elements
  array[offset    ] = te[0]
  array[offset + 1] = te[1]
  array[offset + 2] = te[2]
  array[offset + 3] = te[3]
  array[offset + 4] = te[4]
  array[offset + 5] = te[5]
  array[offset + 6] = te[6]
  array[offset + 7] = te[7]
  array[offset + 8]  = te[8]
  array
end

#from_array(array) ⇒ Object 



151
152
153
154
 
# File 'lib/mittsu/math/matrix3.rb', line 151

def from_array(array)
  self.elements[0..array.length] = (array)
  self
end

#identity ⇒ Object 



25
26
27
28
29
30
31
32
 
# File 'lib/mittsu/math/matrix3.rb', line 25

def identity
  self.set(
    1.0, 0.0, 0.0,
    0.0, 1.0, 0.0,
    0.0, 0.0, 1.0
  )
  self
end

#inverse(matrix, throw_on_invertible = false) ⇒ Object 



74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
 
# File 'lib/mittsu/math/matrix3.rb', line 74

def inverse(matrix, throw_on_invertible = false)
  # input: Mittsu::Matrix4
  # (based on http:#code.google.com/p/webgl-mjs/)
  me = matrix.elements
  te = self.elements
  te[0] =   me[10] * me[5] - me[6] * me[9]
  te[1] = - me[10] * me[1] + me[2] * me[9]
  te[2] =   me[6] * me[1] - me[2] * me[5]
  te[3] = - me[10] * me[4] + me[6] * me[8]
  te[4] =   me[10] * me[0] - me[2] * me[8]
  te[5] = - me[6] * me[0] + me[2] * me[4]
  te[6] =   me[9] * me[4] - me[5] * me[8]
  te[7] = - me[9] * me[0] + me[1] * me[8]
  te[8] =   me[5] * me[0] - me[1] * me[4]
  det = me[0] * te[0] + me[1] * te[3] + me[2] * te[6]
  # no inverse
  if det.zero?
    msg = "Mittsu::Matrix3#inverse: can't invert matrix, determinant is 0"
    if throw_on_invertible
      raise Error.new(msg)
    else
      puts "WARNING: #{msg}"
      # THREE.warn(msg)
    end
    self.identity
    return self
  end
  self.multiply_scalar(1.0 / det)
  self
end

#multiply_scalar(s) ⇒ Object 



61
62
63
64
65
66
67
 
# File 'lib/mittsu/math/matrix3.rb', line 61

def multiply_scalar(s)
  te = self.elements
  te[0] *= s; te[3] *= s; te[6] *= s
  te[1] *= s; te[4] *= s; te[7] *= s
  te[2] *= s; te[5] *= s; te[8] *= s
  self
end

#normal_matrix(m) ⇒ Object 



127
128
129
130
131
 
# File 'lib/mittsu/math/matrix3.rb', line 127

def normal_matrix(m)
  # input: THREE.Matrix4
  self.inverse(m).transpose
  self
end

#set(n11, n12, n13, n21, n22, n23, n31, n32, n33) ⇒ Object 



17
18
19
20
21
22
23
 
# File 'lib/mittsu/math/matrix3.rb', line 17

def set(n11, n12, n13, n21, n22, n23, n31, n32, n33)
  te = self.elements
  te[0] = n11.to_f; te[3] = n12.to_f; te[6] = n13.to_f
  te[1] = n21.to_f; te[4] = n22.to_f; te[7] = n23.to_f
  te[2] = n31.to_f; te[5] = n32.to_f; te[8] = n33.to_f
  self
end

#to_a ⇒ Object 



156
157
158
159
160
161
162
163
 
# File 'lib/mittsu/math/matrix3.rb', line 156

def to_a
  te = self.elements
  [
    te[0], te[1], te[2],
    te[3], te[4], te[5],
    te[6], te[7], te[8]
  ]
end

#transpose ⇒ Object 



105
106
107
108
109
110
111
 
# File 'lib/mittsu/math/matrix3.rb', line 105

def transpose
  m = self.elements
  tmp = m[1]; m[1] = m[3]; m[3] = tmp
  tmp = m[2]; m[2] = m[6]; m[6] = tmp
  tmp = m[5]; m[5] = m[7]; m[7] = tmp
  self
end

#transpose_into_array(r) ⇒ Object 



133
134
135
136
137
138
139
140
141
142
143
144
145
 
# File 'lib/mittsu/math/matrix3.rb', line 133

def transpose_into_array(r)
  m = self.elements
  r[0] = m[0]
  r[1] = m[3]
  r[2] = m[6]
  r[3] = m[1]
  r[4] = m[4]
  r[5] = m[7]
  r[6] = m[2]
  r[7] = m[5]
  r[8] = m[8]
  self
end