indexing
	description: "Projectors for widgets using limited-sized buffer."
	legal: "See notice at end of class."
	status: "See notice at end of class."
	author: "Etienne Amodeo"
	date: "$Date: 2006-10-03 11:19:29 -0700 (Tue, 03 Oct 2006) $"
	revision: "$Revision: 64081 $"

class interface
	EV_MODEL_BUFFER_PROJECTOR

create 
	make_with_buffer (a_world: like world; a_drawing_area: EV_DRAWING_AREA)
			-- Create with `a_world' and `a_drawing_area'.
		require
			a_world_not_void: a_world /= Void
			a_drawing_area_not_void: a_drawing_area /= Void

feature -- Access

	area: EV_DRAWABLE
			-- Area associated with widget.
			-- `Void' if no buffer is used.
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	area_x: INTEGER_32
			-- Coordinates of top-left corner of displayed part of drawable.
			-- (0, 0) when no buffer is used.
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	area_y: INTEGER_32
			-- Coordinates of top-left corner of displayed part of drawable.
			-- (0, 0) when no buffer is used.
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	buffer_scale_factor: REAL_32 is 1.5
			-- The buffer is Buffer_scale_factor times bigger than the window.

	drawable: EV_DRAWABLE
			-- Drawable surface (screen, drawing area or pixmap).
			-- (from EV_MODEL_DRAWER)

	drawable_in_the_cell: EV_DRAWABLE
			-- Object on which the diagram should be drawn.
			-- (from EV_MODEL_BUFFER_MANAGER)

	drawable_cell: CELL [EV_DRAWABLE]
			-- Cell that contains drawable.
			-- (from EV_MODEL_BUFFER_MANAGER)

	drawable_position: EV_COORDINATE
			-- Position of drawable relative to world.
			-- (from EV_MODEL_BUFFER_MANAGER)

	ev_application: EV_APPLICATION
			-- Current application. This once feature must be called
			-- only if the application has been created
			-- (from EV_SHARED_APPLICATION)
		ensure -- from EV_SHARED_APPLICATION
			result_not_void: Result /= Void

	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)

	is_world_too_large: BOOLEAN

	offset_x: INTEGER_32
			-- Everyting is drawn offset_x pixels to the right.

	offset_y: INTEGER_32
			-- Everyting is drawen offset_y pixels to bottom.

	process_events_and_idle
			-- Call `process_events' and `idle_actions' on Ev_application.
			-- (from EV_SHARED_APPLICATION)

	widget: EV_WIDGET
			-- `device' if conforms to EV_WIDGET.
			-- `Void' otherwise.
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	world: EV_MODEL_WORLD
			-- Figure-world that will be projected.
			-- (from EV_MODEL_PROJECTOR)

	world_as_pixmap (a_border: INTEGER_32): EV_PIXMAP
			-- Image of the world with `a_border'.
		require
			a_border_positive: a_border >= 0
		ensure
			result_not_void: Result /= Void
	
feature -- Comparison

	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
			-- Is `other' attached to an object considered
			-- equal to current object?
			-- (from ANY)
		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

	buffer_used: BOOLEAN is True

	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_figure_selected: BOOLEAN
			-- Was button pointer pressed on a figure?
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	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 -- Status setting

	set_world (a_world: like world)
			-- Set world to `a_world'.
			-- (from EV_MODEL_PROJECTOR)
		require -- from EV_MODEL_PROJECTOR
			a_world_exists: a_world /= Void
		ensure -- from EV_MODEL_PROJECTOR
			world_assigned: world = a_world
	
feature -- Element change

	change_area_position (a_x, a_y: INTEGER_32)
			-- area has moved to (`a_x', `a_y') of drawable.

	set_drawable_cell (a_drawable_cell: like drawable_cell)
			-- Set drawable to `a_drawable'.
			-- (from EV_MODEL_BUFFER_MANAGER)
		require -- from EV_MODEL_BUFFER_MANAGER
			a_drawable_cell_not_void: a_drawable_cell /= Void
		ensure -- from EV_MODEL_BUFFER_MANAGER
			assigned: drawable_cell = a_drawable_cell

	set_drawable_cell_and_position (a_drawable_cell: like drawable_cell; a_position: EV_COORDINATE)
			-- Set `a_drawable' to drawable.
			-- (from EV_MODEL_BUFFER_MANAGER)
		require -- from EV_MODEL_BUFFER_MANAGER
			a_drawable_not_void: a_drawable_cell /= Void
			a_position_not_void: a_position /= Void
		ensure -- from EV_MODEL_BUFFER_MANAGER
			assigned: drawable_cell = a_drawable_cell

	set_drawable_position (a_drawable_position: EV_COORDINATE)
			-- Set drawable_position to `a_drawable_position'.
			-- (from EV_MODEL_BUFFER_MANAGER)
		require -- from EV_MODEL_BUFFER_MANAGER
			a_drawable_position_not_void: a_drawable_position /= Void
		ensure -- from EV_MODEL_BUFFER_MANAGER
			drawable_position_assigned: drawable_position = a_drawable_position
	
feature -- Duplication

	copy (other: like Current)
			-- Update current object using fields of object attached
			-- to `other', so as to yield equal objects.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_equal: is_equal (other)

	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

	clear_device
			-- Erase entire canvas.
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	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)

	is_projecting: BOOLEAN
			-- Is a project currently being performed?
			-- Then, do not start a new one.
			-- (from EV_MODEL_PROJECTION_ROUTINES)

	project
			-- Make a standard projection of world on device.
			-- (from EV_MODEL_WIDGET_PROJECTOR)

	register_figure (a_figure: EV_MODEL; a_routine: PROCEDURE [ANY, TUPLE [EV_MODEL]])
			-- Assign `a_routine' for drawing of `a_figure'.
			-- (from EV_MODEL_PROJECTION_ROUTINES)
		require -- from EV_MODEL_PROJECTION_ROUTINES
			a_figure_exists: a_figure /= Void
			a_routine_exists: a_routine /= Void
		ensure -- from EV_MODEL_PROJECTION_ROUTINES
			draw_routines.item (a_figure.draw_id) = a_routine
	
feature -- Implementation

	default_colors: EV_STOCK_COLORS
			-- Once access to `EV_STOCK_COLORS'.
			-- (from EV_MODEL_PROJECTION_ROUTINES)
		require -- from  EV_MODEL_DRAWER
			True
	
feature -- Basic Operations

	draw_grid
			-- Draw grid on canvas.
			-- `world.point' is the origin of the grid.
			-- (from EV_MODEL_DRAWER)
	
feature -- Display updates

	full_project
			-- Project entire area.

	project_rectangle (u: EV_RECTANGLE)
			-- Project area under `u'

	update
			-- Update display by drawing the right part of the buffer on area.

	update_rectangle (u: EV_RECTANGLE; a_x, a_y: INTEGER_32)
			-- Flush `u' on area at (`a_x', `a_y').
		require -- from EV_MODEL_WIDGET_PROJECTOR
			buffer_used: buffer_used
	
feature -- Figure drawing

	draw_figure_arc (arc: EV_MODEL_ARC)
			-- Draw standard representation of `arc' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			arc_not_void: arc /= Void

	draw_figure_dot (dot: EV_MODEL_DOT)
			-- Draw standard representation of `dot' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			dot_not_void: dot /= Void

	draw_figure_ellipse (ellipse: EV_MODEL_ELLIPSE)
			-- Draw standard representation of `ellipse' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			ellipse_not_void: ellipse /= Void

	draw_figure_equilateral (eql: EV_MODEL_EQUILATERAL)
			-- Draw standard representation of `eql' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			eql_not_void: eql /= Void

	draw_figure_line (line: EV_MODEL_LINE)
			-- Draw standard representation of `line' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			line_not_void: line /= Void

	draw_figure_parallelogram (parallelogram: EV_MODEL_PARALLELOGRAM)
			-- Draw standad representation of `parallelogram' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			parallelogram_not_void: parallelogram /= Void

	draw_figure_picture (picture: EV_MODEL_PICTURE)
			-- Draw standard representation of `picture' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			picture_not_void: picture /= Void

	draw_figure_pie_slice (slice: EV_MODEL_PIE_SLICE)
			-- Draw standard representation of `slice' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			slice_not_void: slice /= Void

	draw_figure_polygon (polygon: EV_MODEL_POLYGON)
			-- Draw standard representation of `polygon' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			polygon_not_void: polygon /= Void

	draw_figure_polyline (line: EV_MODEL_POLYLINE)
			-- Draw standard representation of `polyline' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			line_not_void: line /= Void

	draw_figure_rectangle (rectangle: EV_MODEL_RECTANGLE)
			-- Draw standard representation of `rectangle' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			rectangle_not_void: rectangle /= Void

	draw_figure_rotated_arc (arc: EV_MODEL_ROTATED_ARC)
			-- Draw standard representation of `arc' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			arc_not_void: arc /= Void

	draw_figure_rotated_ellipse (ellipse: EV_MODEL_ROTATED_ELLIPSE)
			-- Draw standard representation of `ellipse' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			ellipse_not_void: ellipse /= Void

	draw_figure_rotated_pie_slice (slice: EV_MODEL_ROTATED_PIE_SLICE)
			-- Draw standard representation of `slice' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			slice_not_void: slice /= Void

	draw_figure_rounded_parallelogram (f: EV_MODEL_ROUNDED_PARALLELOGRAM)
			-- Draw standart representation of `f' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			parallelogram_not_void: f /= Void

	draw_figure_rounded_rectangle (f: EV_MODEL_ROUNDED_RECTANGLE)
			-- Draw standard representation of `f' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			f_not_void: f /= Void

	draw_figure_star (star: EV_MODEL_STAR)
			-- Draw standard representation of `star' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			star_not_void: star /= Void

	draw_figure_text (text_figure: EV_MODEL_TEXT)
			-- Draw standard representation of `text_figure' to canvas.
			-- (from EV_MODEL_DRAWER)
		require -- from EV_MODEL_DRAWING_ROUTINES
			text_figure_not_void: text_figure /= Void
	
feature -- Output

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

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

	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)
	
invariant
	right_drawable_in_the_cell: drawable = drawable_in_the_cell

		-- from EV_MODEL_PROJECTOR
	world_exists: world /= Void

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

		-- from EV_MODEL_DRAWER
	drawable_not_void: drawable /= Void

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_MODEL_BUFFER_PROJECTOR