class Proj::CoordinateSystem
Represents a coordinate system for a {Crs CRS}
Public Class Methods
Create a CoordinateSystem
@param context [Context] The context associated with the CoordinateSystem
@param cs_type
[PJ_COORDINATE_SYSTEM_TYPE] Coordinate
system type @param axes [Array<PJ_AXIS_DESCRIPTION>] Array of Axes
@return [CoordinateSystem]
# File lib/proj/coordinate_system.rb, line 13 def self.create(cs_type, axes, context) axes_ptr = FFI::MemoryPointer.new(Api::PJ_AXIS_DESCRIPTION, axes.size) axes.each_with_index do |axis, i| axis_description_target = Api::PJ_AXIS_DESCRIPTION.new(axes_ptr[i]) axis_description_source = axis.to_description axis_description_target.to_ptr.__copy_from__(axis_description_source.to_ptr, Api::PJ_AXIS_DESCRIPTION.size) end pointer = Api.proj_create_cs(context, cs_type, axes.count, axes_ptr) Error.check_context(context) self.create_object(pointer, context) end
Create a CartesiansCS 2D coordinate system
@param context [Context] The context associated with the CoordinateSystem
@param cs_type
[PJ_COORDINATE_SYSTEM_TYPE] Coordinate
system type @param unit_name [String] Name of the unit. Default is nil. @param unit_conv_factor [Float] Unit
conversion factor to SI. Default is 0.
@return [CoordinateSystem]
# File lib/proj/coordinate_system.rb, line 64 def self.create_cartesian_2d(context, cs_type, unit_name: nil, unit_conv_factor: 0) pointer = Api.proj_create_cartesian_2D_cs(context, cs_type, unit_name, unit_conv_factor) Error.check_context(context) self.create_object(pointer, context) end
Create an Ellipsoidal 2D CoordinateSystem
@param context [Context] The context associated with the CoordinateSystem
@param cs_type
[PJ_COORDINATE_SYSTEM_TYPE] Coordinate
system type @param unit_name [String] Name of the angular units. Or nil for degree @param unit_conv_factor [Float] Conversion
factor from the angular unit to radian. Set to 0 if unit name is degree
@return [CoordinateSystem]
# File lib/proj/coordinate_system.rb, line 34 def self.create_ellipsoidal_2d(cs_type, context, unit_name: nil, unit_conv_factor: 0) pointer = Api.proj_create_ellipsoidal_2D_cs(context, cs_type, unit_name, unit_conv_factor) Error.check_context(context) self.create_object(pointer, context) end
Create an Ellipsoidal 3D CoordinateSystem
@param context [Context] The context associated with the CoordinateSystem
@param cs_type
[PJ_COORDINATE_SYSTEM_TYPE] Coordinate
system type @param horizontal_angular_unit_name [String] Name of the angular units. Or nil for degree @param horizontal_angular_unit_conv_factor [Float] Conversion
factor from the angular unit to radian. Set to 0 if horizontal_angular_unit_name name is degree @param vertical_linear_unit_name [String] Name of the angular units. Or nil for meter @param vertical_linear_unit_conv_factor [Float] Conversion
factor from the linear unit to meter. Set to 0 if vertical_linear_unit_name name is meter
@return [CoordinateSystem]
# File lib/proj/coordinate_system.rb, line 50 def self.create_ellipsoidal_3d(cs_type, context, horizontal_angular_unit_name: nil, horizontal_angular_unit_conv_factor: 0, vertical_linear_unit_name: nil, vertical_linear_unit_conv_factor: 0) pointer = Api.proj_create_ellipsoidal_3D_cs(context, cs_type, horizontal_angular_unit_name, horizontal_angular_unit_conv_factor, vertical_linear_unit_name, vertical_linear_unit_conv_factor) Error.check_context(context) self.create_object(pointer, context) end
Public Instance Methods
Returns information about all axes
@return [Array<AxisInfo>]
# File lib/proj/coordinate_system.rb, line 131 def axes self.axis_count.times.map do |index| self.axis_info(index) end end
Returns the number of axes in the coordinate system
@see proj.org/development/reference/functions.html#c.proj_cs_get_axis_count
@return [Integer]
# File lib/proj/coordinate_system.rb, line 88 def axis_count result = Api.proj_cs_get_axis_count(self.context, self) if result == -1 Error.check_object(self) end result end
Returns information about a single axis
@see proj.org/development/reference/functions.html#c.proj_cs_get_axis_info
@param index [Integer] Index of the axis
@return [AxisInfo]
# File lib/proj/coordinate_system.rb, line 103 def axis_info(index) p_name = FFI::MemoryPointer.new(:pointer) p_abbreviation = FFI::MemoryPointer.new(:pointer) p_direction = FFI::MemoryPointer.new(:pointer) p_unit_conv_factor = FFI::MemoryPointer.new(:double) p_unit_name = FFI::MemoryPointer.new(:pointer) p_unit_auth_name = FFI::MemoryPointer.new(:pointer) p_unit_code = FFI::MemoryPointer.new(:pointer) result = Api.proj_cs_get_axis_info(self.context, self, index, p_name, p_abbreviation, p_direction, p_unit_conv_factor, p_unit_name, p_unit_auth_name, p_unit_code) unless result Error.check_object(self) end AxisInfo.new(name: p_name.read_pointer.read_string, abbreviation: p_abbreviation.read_pointer.read_string_to_null, direction: p_direction.read_pointer.read_string_to_null, unit_conv_factor: p_unit_conv_factor.read_double, unit_name: p_unit_name.read_pointer.read_string_to_null, unit_auth_name: p_unit_auth_name.read_pointer.read_string_to_null, unit_code: p_unit_code.read_pointer.read_string_to_null) end
Returns the type of the coordinate system
@see proj.org/development/reference/functions.html#c.proj_cs_get_type
@return [PJ_COORDINATE_SYSTEM_TYPE]
# File lib/proj/coordinate_system.rb, line 75 def cs_type result = Api.proj_cs_get_type(self.context, self) if result == :PJ_CS_TYPE_UNKNOWN Error.check_object(self) end result end