indexing
	description: "Color modeled as red, green, blue intensitieseach with range [0,1]."
	legal: "See notice at end of class."
	keywords: "color, pixel, rgb, 8, 16, 24"
	status: "See notice at end of class."
	date: "$Date: 2006-03-16 17:10:42 -0800 (Thu, 16 Mar 2006) $"
	revision: "$Revision: 57525 $"

class interface
	EV_COLOR

create 
	default_create
			-- Standard creation procedure.
			-- (from EV_ANY)
		require -- from  ANY
			True
		ensure then -- from EV_ANY
			is_coupled: implementation /= Void
			is_initialized: is_initialized
			default_create_called_set: default_create_called
			is_in_default_state: is_in_default_state

	make_with_8_bit_rgb (an_8_bit_red, an_8_bit_green, an_8_bit_blue: INTEGER_32)
			-- Create with `a_red', `a_green', `a_blue', and default name.
		require
			red_within_range: an_8_bit_red >= 0 and an_8_bit_red <= max_8_bit
			green_within_range: an_8_bit_green >= 0 and an_8_bit_green <= max_8_bit
			blue_within_range: an_8_bit_blue >= 0 and an_8_bit_blue <= max_8_bit
		ensure
			red_assigned: red_8_bit = an_8_bit_red
			green_assigned: green_8_bit = an_8_bit_green
			blue_assigned: blue_8_bit = an_8_bit_blue

	make_with_rgb (a_red, a_green, a_blue: REAL_32)
			-- Create with `a_red', `a_green', `a_blue', and default name.
		require
			a_red_within_range: a_red >= 0 and then a_red <= 1
			a_green_within_range: a_green >= 0 and then a_green <= 1
			a_blue_within_range: a_blue >= 0 and then a_blue <= 1
		ensure
			red_assigned: (red - a_red).abs <= delta
			green_assigned: (green - a_green).abs <= delta
			blue_assigned: (blue - a_blue).abs <= delta

feature -- Access

	blue: REAL_32
			-- Intensity of blue component. Range: [0,1]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.blue

	data: ANY
			-- Arbitrary user data may be stored here.
			-- (from EV_ANY)

	generating_type: STRING_8
			-- Name of current object's generating type
			-- (type of which it is a direct instance)
			-- (from ANY)

	generator: STRING_8
			-- Name of current object's generating class
			-- (base class of the type of which it is a direct instance)
			-- (from ANY)

	green: REAL_32
			-- Intensity of green component. Range: [0,1]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.green

	hue: REAL_32
			-- Hue of the color
		require
			not_destroyed: not is_destroyed

	lightness: REAL_32
			-- Lightness of the color
		require
			not_destroyed: not is_destroyed

	red: REAL_32
			-- Intensity of red component. Range: [0,1]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.red

	saturation: REAL_32
			-- Saturation of the color
		require
			not_destroyed: not is_destroyed
	
feature -- Comparison

	copy (other: like Current)
			-- Update `Current' by setting attributes from `other'.
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_equal: is_equal (other)

	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void
			-- or attached to isomorphic object structures?
			-- (from ANY)
		ensure -- from ANY
			shallow_implies_deep: standard_equal (some, other) implies Result
			both_or_none_void: (some = Void) implies (Result = (other = Void))
			same_type: (Result and (some /= Void)) implies some.same_type (other)
			symmetric: Result implies deep_equal (other, some)

	frozen equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached
			-- to objects considered equal?
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

	is_equal (other: like Current): BOOLEAN
			-- Does `Current' look the same color as `other'?
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			symmetric: Result implies other.is_equal (Current)
			consistent: standard_is_equal (other) implies Result

	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached to
			-- field-by-field identical objects of the same type?
			-- Always uses default object comparison criterion.
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

	frozen standard_is_equal (other: like Current): BOOLEAN
			-- Is `other' attached to an object of the same type
			-- as current object, and field-by-field identical to it?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			same_type: Result implies same_type (other)
			symmetric: Result implies other.standard_is_equal (Current)
	
feature -- Status report

	conforms_to (other: ANY): BOOLEAN
			-- Does type of current object conform to type
			-- of `other' (as per Eiffel: The Language, chapter 13)?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void

	is_hashable: BOOLEAN
			-- May current object be hashed?
			-- (True if it is not its type's default.)
			-- (from HASHABLE)
		ensure -- from HASHABLE
			ok_if_not_default: Result implies (Current /= default)

	same_type (other: ANY): BOOLEAN
			-- Is type of current object identical to type of `other'?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			definition: Result = (conforms_to (other) and other.conforms_to (Current))
	
feature -- Element change

	set_blue (a_blue: REAL_32)
			-- Assign `a_blue' to blue.
		require
			not_destroyed: not is_destroyed
			blue_within_range: a_blue >= 0 and then a_blue <= 1
		ensure
			blue_assigned: (blue - a_blue).abs <= delta

	set_data (some_data: like data)
			-- Assign `some_data' to data.
			-- (from EV_ANY)
		require -- from EV_ANY
			not_destroyed: not is_destroyed
		ensure -- from EV_ANY
			data_assigned: data = some_data

	set_green (a_green: REAL_32)
			-- Assign `a_green' to green.
		require
			not_destroyed: not is_destroyed
			within_range: a_green >= 0 and then a_green <= 1
		ensure
			green_assigned: (green - a_green).abs <= delta

	set_red (a_red: REAL_32)
			-- Assign `a_red' to red.
		require
			not_destroyed: not is_destroyed
			within_range: a_red >= 0 and then a_red <= 1
		ensure
			red_assigned: (red - a_red).abs <= delta

	set_rgb (a_red, a_green, a_blue: REAL_32)
			-- Assign `a_red', `a_green' and `a_blue'
			-- to red, green and blue respectively.
		require
			not_destroyed: not is_destroyed
			red_within_range: a_red >= 0 and then a_red <= 1
			green_within_range: a_green >= 0 and then a_green <= 1
			blue_within_range: a_blue >= 0 and then a_blue <= 1
		ensure
			red_assigned: (red - a_red).abs <= delta
			green_assigned: (green - a_green).abs <= delta
			blue_assigned: (blue - a_blue).abs <= delta
	
feature -- Conversion

	blue_16_bit: INTEGER_32
			-- Intensity of blue component as an 16 bit unsigned integer.
			-- Range [0,65535]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.blue_16_bit

	blue_8_bit: INTEGER_32
			-- Intensity of blue component as an 8 bit unsigned integer.
			-- Range [0,255]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.blue_8_bit

	green_16_bit: INTEGER_32
			-- Intensity of green component as an 16 bit unsigned integer.
			-- Range [0,65535]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.green_16_bit

	green_8_bit: INTEGER_32
			-- Intensity of green component as an 8 bit unsigned integer.
			-- Range [0,255]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.green_8_bit

	red_16_bit: INTEGER_32
			-- Intensity of red component as an 16 bit unsigned integer.
			-- Range [0,65535]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.red_16_bit

	red_8_bit: INTEGER_32
			-- Intensity of red component as an 8 bit unsigned integer.
			-- Range [0,255]
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.red_8_bit

	rgb_24_bit: INTEGER_32
			-- red, green and blue intensities packed into 24 bits
			-- with 8 bits per colour and blue in the least significant 8 bits.
		require
			not_destroyed: not is_destroyed
		ensure
			bridge_ok: Result = implementation.rgb_24_bit

	set_blue_with_16_bit (a_16_bit_blue: INTEGER_32)
			-- Set blue from `a_16_bit_blue' intinsity.
		require
			not_destroyed: not is_destroyed
			within_range: a_16_bit_blue >= 0 and then a_16_bit_blue <= max_16_bit
		ensure
			blue_assigned: blue_16_bit = a_16_bit_blue

	set_blue_with_8_bit (an_8_bit_blue: INTEGER_32)
			-- Set blue from `an_8_bit_blue' intinsity.
		require
			not_destroyed: not is_destroyed
			within_range: an_8_bit_blue >= 0 and then an_8_bit_blue <= max_8_bit
		ensure
			blue_assigned: blue_8_bit = an_8_bit_blue

	set_green_with_16_bit (a_16_bit_green: INTEGER_32)
			-- Set green from `a_16_bit_green' intinsity.
		require
			not_destroyed: not is_destroyed
			within_range: a_16_bit_green >= 0 and then a_16_bit_green <= max_16_bit
		ensure
			green_assigned: green_16_bit = a_16_bit_green

	set_green_with_8_bit (an_8_bit_green: INTEGER_32)
			-- Set green from `an_8_bit_green' intinsity.
		require
			not_destroyed: not is_destroyed
			within_range: an_8_bit_green >= 0 and then an_8_bit_green <= max_8_bit
		ensure
			green_assigned: green_8_bit = an_8_bit_green

	set_red_with_16_bit (a_16_bit_red: INTEGER_32)
			-- Set red from `a_8_bit_red' intinsity.
		require
			not_destroyed: not is_destroyed
			within_range: a_16_bit_red >= 0 and then a_16_bit_red <= max_16_bit
		ensure
			red_assigned: red_16_bit = a_16_bit_red

	set_red_with_8_bit (an_8_bit_red: INTEGER_32)
			-- Set red from `an_8_bit_red' intinsity.
		require
			not_destroyed: not is_destroyed
			within_range: an_8_bit_red >= 0 and then an_8_bit_red <= max_8_bit
		ensure
			red_assigned: red_8_bit = an_8_bit_red

	set_rgb_with_16_bit (a_16_bit_red, a_16_bit_green, a_16_bit_blue: INTEGER_32)
			-- Set intensities  from `a_16_bit_red', `a_16_bit_green', and
			-- `a_16_bit_blue' intensity. (16 bits per channel.)
		require
			not_destroyed: not is_destroyed
			red_within_range: a_16_bit_red >= 0 and a_16_bit_red <= max_16_bit
			green_within_range: a_16_bit_green >= 0 and a_16_bit_green <= max_16_bit
			blue_within_range: a_16_bit_blue >= 0 and a_16_bit_blue <= max_16_bit
		ensure
			red_assigned: red_16_bit = a_16_bit_red
			green_assigned: green_16_bit = a_16_bit_green
			blue_assigned: blue_16_bit = a_16_bit_blue

	set_rgb_with_24_bit (a_24_bit_rgb: INTEGER_32)
			-- Set intensities from `a_24_bit_rgb' value
			-- with blue in the least significant 8 bits.
		require
			not_destroyed: not is_destroyed
			within_range: a_24_bit_rgb >= 0 and a_24_bit_rgb <= max_24_bit
		ensure
			rgb_assigned: rgb_24_bit = a_24_bit_rgb

	set_rgb_with_8_bit (an_8_bit_red, an_8_bit_green, an_8_bit_blue: INTEGER_32)
			-- Set intensities  from `an_8_bit_red', `an_8_bit_green', and
			-- `an_8_bit_blue' intensity. (8 bits per channel.)
		require
			not_destroyed: not is_destroyed
			red_within_range: an_8_bit_red >= 0 and an_8_bit_red <= max_8_bit
			green_within_range: an_8_bit_green >= 0 and an_8_bit_green <= max_8_bit
			blue_within_range: an_8_bit_blue >= 0 and an_8_bit_blue <= max_8_bit
		ensure
			red_assigned: red_8_bit = an_8_bit_red
			green_assigned: green_8_bit = an_8_bit_green
			blue_assigned: blue_8_bit = an_8_bit_blue
	
feature -- Duplication

	frozen deep_copy (other: like Current)
			-- Effect equivalent to that of:
			--		copy (`other' . deep_twin)
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			deep_equal: deep_equal (Current, other)

	frozen deep_twin: like Current
			-- New object structure recursively duplicated from Current.
			-- (from ANY)
		ensure -- from ANY
			deep_equal: deep_equal (Current, Result)

	frozen standard_copy (other: like Current)
			-- Copy every field of `other' onto corresponding field
			-- of current object.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_standard_equal: standard_is_equal (other)

	frozen standard_twin: like Current
			-- New object field-by-field identical to `other'.
			-- Always uses default copying semantics.
			-- (from ANY)
		ensure -- from ANY
			standard_twin_not_void: Result /= Void
			equal: standard_equal (Result, Current)

	frozen twin: like Current
			-- New object equal to `Current'
			-- twin calls copy; to change copying/twining semantics, redefine copy.
			-- (from ANY)
		ensure -- from ANY
			twin_not_void: Result /= Void
			is_equal: Result.is_equal (Current)
	
feature -- Basic operations

	frozen default: like Current
			-- Default value of object's type
			-- (from ANY)

	frozen default_pointer: POINTER
			-- Default value of type `POINTER'
			-- (Avoid the need to write `p'.default for
			-- some `p' of type `POINTER'.)
			-- (from ANY)

	default_rescue
			-- Process exception for routines with no Rescue clause.
			-- (Default: do nothing.)
			-- (from ANY)

	frozen do_nothing
			-- Execute a null action.
			-- (from ANY)
	
feature -- Command

	destroy
			-- Destroy underlying native toolkit object.
			-- Render `Current' unusable.
			-- (from EV_ANY)
		ensure -- from EV_ANY
			is_destroyed: is_destroyed
	
feature -- Constants

	max_16_bit: INTEGER_32 is 65535
			-- Maximum value for 16 bit unsigned integers.

	max_24_bit: INTEGER_32 is 16777215
			-- Maximum value for 24 bit unsigned integers.

	max_8_bit: INTEGER_32 is 255
			-- Maximum value for 8 bit unsigned integers.
	
feature -- Hashable

	hash_code: INTEGER_32
			-- Hash code value
		ensure -- from HASHABLE
			good_hash_value: Result >= 0
	
feature -- Output

	io: STD_FILES
			-- Handle to standard file setup
			-- (from ANY)

	out: STRING_8
			-- Textual representation.

	print (some: ANY)
			-- Write terse external representation of `some'
			-- on standard output.
			-- (from ANY)

	frozen tagged_out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- Was declared in ANY as synonym of out.
			-- (from ANY)
	
feature -- Platform

	operating_environment: OPERATING_ENVIRONMENT
			-- Objects available from the operating system
			-- (from ANY)
	
feature -- Status Report

	is_destroyed: BOOLEAN
			-- Is `Current' no longer usable?
			-- (from EV_ANY)
		ensure -- from EV_ANY
			bridge_ok: Result = implementation.is_destroyed
	
invariant
	red_within_range: red >= 0 and red <= 1
	green_within_range: green >= 0 and green <= 1
	blue_within_range: blue >= 0 and blue <= 1
	red_8_bit_within_range: red_8_bit >= 0 and red_8_bit <= max_8_bit
	green_8_bit_within_range: green_8_bit >= 0 and green_8_bit <= max_8_bit
	blue_8_bit_within_range: blue_8_bit >= 0 and blue_8_bit <= max_8_bit
	red_16_bit_within_range: red_16_bit >= 0 and red_16_bit <= max_16_bit
	green_16_bit_within_range: green_16_bit >= 0 and green_16_bit <= max_16_bit
	blue_16_bit_within_range: blue_16_bit >= 0 and blue_16_bit <= max_16_bit
	rgb_24_bit_within_range: rgb_24_bit >= 0 and rgb_24_bit <= max_24_bit
	red_16_bit_conversion: ((red * max_16_bit) - red_16_bit).abs <= delta * max_16_bit
	red_8_bit_conversion: ((red * max_8_bit) - red_8_bit).abs <= delta * max_8_bit
	green_16_bit_conversion: ((green * max_16_bit) - green_16_bit).abs <= delta * max_16_bit
	green_8_bit_conversion: ((green * max_8_bit) - green_8_bit).abs < delta * max_8_bit
	blue_16_bit_conversion: ((blue * max_16_bit) - blue_16_bit).abs < delta * max_16_bit
	blue_8_bit_conversion: ((blue * max_8_bit) - blue_8_bit).abs < delta * max_8_bit

		-- from EV_ANY
	is_initialized: is_initialized
	is_coupled: implementation /= Void and then implementation.interface = Current
	default_create_called: default_create_called

		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

indexing
	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
	source: "[
		Eiffel Software
		356 Storke Road, Goleta, CA 93117 USA
		Telephone 805-685-1006, Fax 805-685-6869
		Website http://www.eiffel.com
		Customer support http://support.eiffel.com
	]"

end -- class EV_COLOR