FUNCTION qImage_cw_Ellipse, state, box, edge=edge, noupdate=noupdate

;+
; NAME:
;	qImage_cw_Ellipse
; PURPOSE:
;	Calculate boundary and bounding box for a wedge specified as two points
;	in polar coordinates
; CATEGORY:
;	Compound widget qImage_cw
; CALLING SEQUENCE:
;	Result = qImage_cw_Wedge(state, p_box, )
; INPUTS:
;	state		array[1]; type: structure
;					qImage_cw state structure
; OPTIONAL INPUT PARAMETERS:
;	p_box		array[2,2]; type: float
;					limiting values in phase angle and radius of the wedge
;					in the form [[angle1,radius1],[angle2,radius2]].
;					Angle1 and angle2 are in radians between [-!pi,+!pi].
;					The wedge runs counterclockwise from 'angle1' to 'angle2'
;					over less than 180 degrees: either angle2 > angle1 with
;					angle2-angle1 < !pi or angle2 < angle1 with
;					angle+2*!pi-angle1 < !pi. Always radius1 < radius2.
;
;					If polar_box is not specified then the wedge specified in
;					the qImage_cw widget is used.
;
;					If polar_box is specified then the value is processed by qImage_cw_Box.
;					This will update the qImage_cw widget, but will also slightly modify
;					polar_box in such a way that the two corners of the wedge coincide with
;					integer pixel locations (the values returned in 'box')
;					(set /noupdate to bypass this step)
;	/noupdate		Only used if polar_box is specified. Bypasses a call to
;					qImage_cw_Box (which updates the position widgets).
; OUTPUTS:
;	result		array[2,2]; type: integer
;					corners of the smallest square in the image that completely encloses
;					the wedge in pixel coordinates in the form [[x1,y1],[x2,y2].
;					Always x1 <= x2, y1 <= y2.
; OPTIONAL OUTPUT PARAMETERS:
;	wedge		array[2,n]; type: float
;					boundary of wedge as a closed array (first=last point)
;					in rectangular (pixel) coordinates.
;	box			array[2,2]; type: float; default: content of X,Y position widgets in
;					qImage_cw. Two points in the image plane, specified as pixel coordinate
;					values in the same form as the bounding box.
;					'box' is obtained by a call to qImage_cw_Box, and is not modified.
;					If /noupdate is set then qImage_cw_Box is not called and 'box' will be undefined.
; INCLUDE:
	@compile_opt.pro			; On error, return to caller
; CALLS:
;	InitVar, qImage_cw_Box
; PROCEDURE:
;	The origin of the rectangular to polar transformation is the value of
;	the state.wid_center widgets
;	If p_box is specified, and keywords /noupdate and img_center are used then the state structure
;	is not accessed.
; STATE INFO USED:
; STATE INFO MODIFIED:
;	(none)
; MODIFICATION HISTORY:
;	FEB-2000, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
;-

InitVar, noupdate, /key

CASE 1 OF
IsType(box,/undefined): qImage_cw_Box, state, box, /get
1-noupdate			  : qImage_cw_Box, state, box, /put
ELSE:
ENDCASE

n = 101
one = replicate(1,n)
p = p_box[0]+(p_box[2]+(2*!pi)*fix(p_box[2] lt p_box[0])-p_box[0])*findgen(n)/(n-1)

wedge = [ [	p,reverse(p),p[0]], [ p_box[1]*one,p_box[3]*one,p_box[1]] ]

; x,y coordinates of wedge

IF n_elements(img_center) EQ 0 THEN qImage_cw_Box, state, img_center, /center

wedge = img_center#replicate(1,2*n+1)+cv_coord(from_polar=transpose(wedge), /to_rect)

; Calculate the quadrant (1,2,3,4)

quadrant = 1+fix(( (p_box[[0,2]]+2*!pi) mod (2*!pi))/(!pi/2))
IF quadrant[1] LT quadrant[0] THEN quadrant[1] = quadrant[1]+4

x = p_box[[1,3]]#cos(p_box[[0,2]])
y = p_box[[1,3]]#sin(p_box[[0,2]])
b_box = [ [min(x), min(y)], [max(x), max(y)] ]

r = p_box[3]


RETURN, box  &  END