class EvilTransform

blog.csdn.net/coolypf/article/details/8686588 Code from on4wp7.codeplex.com/SourceControl/changeset/view/21483#353936 blog.csdn.net/coolypf/article/details/8569813

Constants

A
BAIDU_PI
EE
PI
VERSION

Public Class Methods

new(*coordinates) click to toggle source

@example

EvilTransform.new(lat: 39.909745000000, lon: 116.359496000000)
EvilTransform.new(39.909745000000, 116.359496000000)
EvilTransform.new([39.909745000000, 116.359496000000])

# File lib/evil_transform.rb, line 18
def initialize(*coordinates)
  coordinates = coordinates.flatten
  if coordinates.last.is_a?(Hash)
    @lat, @lon = coordinates.last.values_at(:lat, :lon)
  else
    @lat, @lon = coordinates
  end
  calculation
end

Public Instance Methods

bgs_to_MGS() click to toggle source

Baidu Geodetic System ==> Mars Geodetic System

# File lib/evil_transform.rb, line 53
def bgs_to_MGS
  x     = @lon - 0.0065; y = @lat - 0.006
  z     = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * BAIDU_PI)
  theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * BAIDU_PI)
  [z * Math.sin(theta), z * Math.cos(theta)]
end

out_of_china?() click to toggle source

# File lib/evil_transform.rb, line 60
def out_of_china?
  @lon < 72.004 || @lon > 137.8347 || @lat < 0.8293 || @lat > 55.8271
end

to_BGS() click to toggle source

Mars Geodetic System ==> Baidu Geodetic System

# File lib/evil_transform.rb, line 46
def to_BGS
  z     = Math.sqrt(@lon * @lon + @lat * @lat) + 0.00002 * Math.sin(@lat * BAIDU_PI)
  theta = Math.atan2(@lat, @lon) + 0.000003 * Math.cos(@lon * BAIDU_PI)
  [z * Math.sin(theta) + 0.006, z * Math.cos(theta) + 0.0065]
end

to_MGS() click to toggle source

World Geodetic System ==> Mars Geodetic System @example Usage

EvilTransform.new(lat: 39.909745000000, lon: 116.359496000000).to_MGS
# => [39.911112866392486, 116.36569790916941]

# File lib/evil_transform.rb, line 32
def to_MGS
  if out_of_china?
    [@lat, @lon]
  else
    [@lat + @d_lat, @lon + @d_lon]
  end
end

to_WGS() click to toggle source

Mars Geodetic System ==> World Geodetic System

# File lib/evil_transform.rb, line 41
def to_WGS
  [@lat - @d_lat, @lon - @d_lon]
end

Protected Instance Methods

calculation() click to toggle source

# File lib/evil_transform.rb, line 82
def calculation
  rad_lat = @lat / 180.0 * PI
  magic   = Math.sin(rad_lat)
  magic   = 1 - EE * magic * magic
  sqrt_magic = Math.sqrt(magic)
  @d_lat = (transform_lat * 180.0) / ((A * (1 - EE)) / (magic * sqrt_magic) * PI)
  @d_lon = (transform_lon * 180.0) / (A / sqrt_magic * Math.cos(rad_lat) * PI)
end

transform_lat() click to toggle source

# File lib/evil_transform.rb, line 66
def transform_lat
  x    = @lon - 105.0; y = @lat - 35.0
  ret  = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.sqrt(x.abs)
  ret += (20.0  * Math.sin(6.0 * x * PI) + 20.0 * Math.sin(2.0 * x * PI)) * 2.0 / 3.0
  ret += (20.0  * Math.sin(y * PI) + 40.0 * Math.sin(y / 3.0 * PI)) * 2.0 / 3.0
  ret += (160.0 * Math.sin(y / 12.0 * PI) + 320 * Math.sin(y * PI / 30.0)) * 2.0 / 3.0
end

transform_lon() click to toggle source

# File lib/evil_transform.rb, line 74
def transform_lon
  x = @lon - 105.0; y = @lat - 35.0
  ret  = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.sqrt(x.abs)
  ret += (20.0  * Math.sin(6.0 * x * PI) + 20.0 * Math.sin(2.0 * x * PI)) * 2.0 / 3.0;
  ret += (20.0  * Math.sin(x * PI) + 40.0 * Math.sin(x / 3.0 * PI)) * 2.0 / 3.0;
  ret += (150.0 * Math.sin(x / 12.0 * PI) + 300.0 * Math.sin(x / 30.0 * PI)) * 2.0 / 3.0;
end