Class: TkComponent::Turtle

Inherits:
Object
  • Object
show all
Defined in:
lib/tk_component/extras/turtle.rb

Constant Summary collapse

FULL_CIRCLE = 
2 * Math::PI

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ Turtle

Returns a new instance of Turtle.



11
12
13
14
15
16
17
18
19
20
 
# File 'lib/tk_component/extras/turtle.rb', line 11

def initialize(options = {})
  @canvas = options[:canvas]
  @current_x = 0
  @current_y = 0
  @angle_unit = :radians
  @current_angle = FULL_CIRCLE / 4.0
  @turtle_down = false
  @color = options[:color] || 'black'
  @width = options[:width] || 1
end

Instance Attribute Details

#canvas ⇒ Object

Returns the value of attribute canvas.



5
6
7
 
# File 'lib/tk_component/extras/turtle.rb', line 5

def canvas
  @canvas
end

#color ⇒ Object

Returns the value of attribute color.



8
9
10
 
# File 'lib/tk_component/extras/turtle.rb', line 8

def color
  @color
end

#current_x ⇒ Object

Returns the value of attribute current_x.



6
7
8
 
# File 'lib/tk_component/extras/turtle.rb', line 6

def current_x
  @current_x
end

#current_y ⇒ Object

Returns the value of attribute current_y.



7
8
9
 
# File 'lib/tk_component/extras/turtle.rb', line 7

def current_y
  @current_y
end

#width ⇒ Object

Returns the value of attribute width.



9
10
11
 
# File 'lib/tk_component/extras/turtle.rb', line 9

def width
  @width
end

Instance Method Details

#clear ⇒ Object 



22
23
24
 
# File 'lib/tk_component/extras/turtle.rb', line 22

def clear
  @canvas.delete('all')
end

#current_point ⇒ Object 



42
43
44
 
# File 'lib/tk_component/extras/turtle.rb', line 42

def current_point
  [@current_x, @current_y]
end

#degrees ⇒ Object Also known as: deg 



85
86
87
 
# File 'lib/tk_component/extras/turtle.rb', line 85

def degrees
  @angle_unit = :degrees
end

#down ⇒ Object 



26
27
28
 
# File 'lib/tk_component/extras/turtle.rb', line 26

def down
  @turtle_down = true
end

#down? ⇒ Boolean

Returns:

  • (Boolean) 


34
35
36
 
# File 'lib/tk_component/extras/turtle.rb', line 34

def down?
  @turtle_down
end

#forward(length) ⇒ Object 



51
52
53
54
55
56
57
58
59
 
# File 'lib/tk_component/extras/turtle.rb', line 51

def forward(length)
  new_x = @current_x + length * Math.cos(@current_angle)
  new_y = @current_y - length * Math.sin(@current_angle)
  if down?
    TkcLine.new(@canvas, [current_point, [new_x, new_y]], fill: @color, width: @width)
  end
  @current_x = new_x
  @current_y = new_y
end

#move_to_center ⇒ Object 



46
47
48
49
 
# File 'lib/tk_component/extras/turtle.rb', line 46

def move_to_center
  @current_x = @canvas.winfo_width / 2
  @current_y = @canvas.winfo_height / 2
end

#point_east ⇒ Object 



73
74
75
 
# File 'lib/tk_component/extras/turtle.rb', line 73

def point_east
  @current_angle = 0.0
end

#point_north ⇒ Object 



69
70
71
 
# File 'lib/tk_component/extras/turtle.rb', line 69

def point_north
  @current_angle = FULL_CIRCLE / 4.0
end

#point_south ⇒ Object 



77
78
79
 
# File 'lib/tk_component/extras/turtle.rb', line 77

def point_south
  @current_angle = FULL_CIRCLE * 3.0 / 4.0
end

#point_west ⇒ Object 



81
82
83
 
# File 'lib/tk_component/extras/turtle.rb', line 81

def point_west
  @current_angle = FULL_CIRCLE / 2.0
end

#radians ⇒ Object Also known as: rad 



90
91
92
 
# File 'lib/tk_component/extras/turtle.rb', line 90

def radians
  @angle_unit = :radians
end

#turn_left(angle) ⇒ Object 



61
62
63
 
# File 'lib/tk_component/extras/turtle.rb', line 61

def turn_left(angle)
  @current_angle = (@current_angle + user_angle(angle)) % FULL_CIRCLE
end

#turn_right(angle) ⇒ Object 



65
66
67
 
# File 'lib/tk_component/extras/turtle.rb', line 65

def turn_right(angle)
  @current_angle = (@current_angle - user_angle(angle)) % FULL_CIRCLE
end

#up ⇒ Object 



30
31
32
 
# File 'lib/tk_component/extras/turtle.rb', line 30

def up
  @turtle_down = false
end

#up? ⇒ Boolean

Returns:

  • (Boolean) 


38
39
40
 
# File 'lib/tk_component/extras/turtle.rb', line 38

def up?
  !down?
end

#user_angle(angle) ⇒ Object 



95
96
97
98
 
# File 'lib/tk_component/extras/turtle.rb', line 95

def user_angle(angle)
  return angle if @angle_unit == :radians
  (angle % 360.0) * FULL_CIRCLE / 360.0
end