Class: PerfectShape::Arc

Inherits:
Shape
  • Object
show all
Includes:
RectangularShape
Defined in:
lib/perfect_shape/arc.rb

Overview

Mostly ported from java.awt.geom: docs.oracle.com/javase/8/docs/api/java/awt/geom/Arc2D.html

Direct Known Subclasses

Ellipse

Constant Summary collapse

TYPES = 
[:open, :chord, :pie]
DEFAULT_OUTLINE_RADIUS = 
BigDecimal('0.001')

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from RectangularShape

#max_x, #max_y

Methods included from PointLocation

#min_x, #min_y

Methods inherited from Shape

#==, #bounding_box, #center_point, #max_x, #max_y, #min_x, #min_y, #normalize_point

Constructor Details

#initialize(type: :open, x: 0, y: 0, width: 1, height: 1, start: 0, extent: 360, center_x: nil, center_y: nil, radius_x: nil, radius_y: nil) ⇒ Arc

Returns a new instance of Arc.



37
38
39
40
41
42
43
44
45
46
47
48
49
 
# File 'lib/perfect_shape/arc.rb', line 37

def initialize(type: :open, x: 0, y: 0, width: 1, height: 1, start: 0, extent: 360, center_x: nil, center_y: nil, radius_x: nil, radius_y: nil)
  if center_x && center_y && radius_x && radius_y
    self.center_x = center_x
    self.center_y = center_y
    self.radius_x = radius_x
    self.radius_y = radius_y
  else
    super(x: x, y: y, width: width, height: height)
  end
  @type = type
  self.start = start
  self.extent = extent
end

Instance Attribute Details

#extent ⇒ Object

Returns the value of attribute extent.



35
36
37
 
# File 'lib/perfect_shape/arc.rb', line 35

def extent
  @extent
end

#start ⇒ Object

Returns the value of attribute start.



35
36
37
 
# File 'lib/perfect_shape/arc.rb', line 35

def start
  @start
end

#type ⇒ Object

Returns the value of attribute type.



34
35
36
 
# File 'lib/perfect_shape/arc.rb', line 34

def type
  @type
end

Instance Method Details

#center_x ⇒ Object 



101
102
103
 
# File 'lib/perfect_shape/arc.rb', line 101

def center_x
  super || @center_x
end

#center_x=(value) ⇒ Object 



117
118
119
120
121
 
# File 'lib/perfect_shape/arc.rb', line 117

def center_x=(value)
  @center_x = BigDecimal(value.to_s)
  @x = nil
  self.radius_x = radius_x if @width
end

#center_y ⇒ Object 



105
106
107
 
# File 'lib/perfect_shape/arc.rb', line 105

def center_y
  super || @center_y
end

#center_y=(value) ⇒ Object 



123
124
125
126
127
 
# File 'lib/perfect_shape/arc.rb', line 123

def center_y=(value)
  @center_y = BigDecimal(value.to_s)
  @y = nil
  self.radius_y = radius_y if @height
end

#contain?(x_or_point, y = nil, outline: false, distance_tolerance: 0) ⇒ @code true

Checks if arc contains point (two-number Array or x, y args)

the arc, false if the point lies outside of the arc’s bounds.

Parameters:

  • x —

    The X coordinate of the point to test.

  • y (defaults to: nil) —

    The Y coordinate of the point to test.

Returns:

  • (@code true) —

    if the point lies within the bound of



147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
 
# File 'lib/perfect_shape/arc.rb', line 147

def contain?(x_or_point, y = nil, outline: false, distance_tolerance: 0)
  x, y = normalize_point(x_or_point, y)
  return unless x && y
  if outline
    if type == :pie && x == center_x && y == center_y
      true
    else
      distance_tolerance = BigDecimal(distance_tolerance.to_s)
      outside_inside_radius_difference = DEFAULT_OUTLINE_RADIUS + distance_tolerance * 2
      outside_radius_difference = inside_radius_difference = outside_inside_radius_difference / 2
      outside_shape = Arc.new(type: type, center_x: center_x, center_y: center_y, radius_x: radius_x + outside_radius_difference, radius_y: radius_y + outside_radius_difference, start: start, extent: extent)
      inside_shape = Arc.new(type: type, center_x: center_x, center_y: center_y, radius_x: radius_x - inside_radius_difference, radius_y: radius_y - inside_radius_difference, start: start, extent: extent)
      outside_shape.contain?(x, y, outline: false) and
        !inside_shape.contain?(x, y, outline: false)
    end
  else
    # Normalize the coordinates compared to the ellipse
    # having a center at 0,0 and a radius of 0.5.
    ellw = width
    return false if (ellw <= 0.0)
    normx = (x - self.x) / ellw - 0.5
    ellh = height
    return false if (ellh <= 0.0)
    normy = (y - self.y) / ellh - 0.5
    dist_sq = (normx * normx) + (normy * normy)
    return false if (dist_sq >= 0.25)
    ang_ext = self.extent.abs
    return true if (ang_ext >= 360.0)
    inarc = contain_angle?(-1*Math.radians_to_degrees(Math.atan2(normy, normx)))
    
    return inarc if type == :pie
    # CHORD and OPEN behave the same way
    if inarc
      return true if ang_ext >= 180.0
      # point must be outside the "pie triangle"
    else
      return false if ang_ext <= 180.0
      # point must be inside the "pie triangle"
    end
    
    # The point is inside the pie triangle iff it is on the same
    # side of the line connecting the ends of the arc as the center.
    angle = Math.degrees_to_radians(-start)
    x1 = Math.cos(angle)
    y1 = Math.sin(angle)
    angle += Math.degrees_to_radians(-extent)
    x2 = Math.cos(angle)
    y2 = Math.sin(angle)
    inside = (Line.relative_counterclockwise(x1, y1, x2, y2, 2*normx, 2*normy) *
                      Line.relative_counterclockwise(x1, y1, x2, y2, 0, 0) >= 0)
    inarc ? !inside : inside
  end
end

#contain_angle?(angle) ⇒ Boolean

Determines whether or not the specified angle is within the angular extents of the arc.

Returns:

  • (Boolean) 


203
204
205
206
207
208
209
210
211
212
213
214
 
# File 'lib/perfect_shape/arc.rb', line 203

def contain_angle?(angle)
  ang_ext = self.extent
  backwards = ang_ext < 0.0
  ang_ext = -ang_ext if backwards
  return true if ang_ext >= 360.0

  angle = Math.normalize_degrees(angle) - Math.normalize_degrees(start)
  angle = -angle if backwards
  angle += 360.0 if angle < 0.0

  (angle >= 0.0) && (angle < ang_ext)
end

#height ⇒ Object 



71
72
73
 
# File 'lib/perfect_shape/arc.rb', line 71

def height
  @radius_y ? @radius_y * BigDecimal('2.0') : super
end

#height=(value) ⇒ Object

Sets height, normalizing to BigDecimal



96
97
98
99
 
# File 'lib/perfect_shape/arc.rb', line 96

def height=(value)
  super
  @radius_y = nil
end

#radius_x ⇒ Object 



109
110
111
 
# File 'lib/perfect_shape/arc.rb', line 109

def radius_x
  @width ? @width/BigDecimal('2.0') : @radius_x
end

#radius_x=(value) ⇒ Object 



129
130
131
132
 
# File 'lib/perfect_shape/arc.rb', line 129

def radius_x=(value)
  @radius_x = BigDecimal(value.to_s)
  @width = nil
end

#radius_y ⇒ Object 



113
114
115
 
# File 'lib/perfect_shape/arc.rb', line 113

def radius_y
  @height ? @height/BigDecimal('2.0') : @radius_y
end

#radius_y=(value) ⇒ Object 



134
135
136
137
 
# File 'lib/perfect_shape/arc.rb', line 134

def radius_y=(value)
  @radius_y = BigDecimal(value.to_s)
  @height = nil
end

#width ⇒ Object 



67
68
69
 
# File 'lib/perfect_shape/arc.rb', line 67

def width
  @radius_x ? @radius_x * BigDecimal('2.0') : super
end

#width=(value) ⇒ Object

Sets width, normalizing to BigDecimal



90
91
92
93
 
# File 'lib/perfect_shape/arc.rb', line 90

def width=(value)
  super
  @radius_x = nil
end

#x ⇒ Object 



59
60
61
 
# File 'lib/perfect_shape/arc.rb', line 59

def x
  @center_x && @radius_x ? @center_x - @radius_x : super
end

#x=(value) ⇒ Object

Sets x, normalizing to BigDecimal



76
77
78
79
80
 
# File 'lib/perfect_shape/arc.rb', line 76

def x=(value)
  super
  @center_x = nil
  self.width = width if @radius_x
end

#y ⇒ Object 



63
64
65
 
# File 'lib/perfect_shape/arc.rb', line 63

def y
  @center_y && @radius_y ? @center_y - @radius_y : super
end

#y=(value) ⇒ Object

Sets y, normalizing to BigDecimal



83
84
85
86
87
 
# File 'lib/perfect_shape/arc.rb', line 83

def y=(value)
  super
  @center_y = nil
  self.height = height if @radius_y
end