Create a draggable, resizable, rotatable rectangle or ellipse.
The 'ellipse' param determines if the displayed object is a rectangle or
ellipse. The object is identical in both cases, only the display changes.
The created object may be queried or controlled programatically by using
the returned api.
The 'rotate' param determines overall behavior of the created object. If
rotate=0, the resulting object (rect or ellipse) is axis aligned. In
terms of the graphical interface it is identical to Matlab's imrect (can
drag by clicking in interior or resize by clicking on edges), although it
is much less cpu intensive. If rotate>0, the resulting object is
rotatable. In addition to the interface for a non-rotatable object, four
control points are present, one at the center of each edge. Three of
these have color given by the 'color' flag, the last has color 'colorc'.
The odd colored control point is used to display orientation. Dragging
this control point or the one opposite changes orientation, dragging the
remaining two resizes the object symmetrically. Finally, when creating a
rotatable object, the first drag determines the major axes (height) of
the object, with the width set to height*rotate (hence the rotate param
also determines aspect ratio of newly created objects). Using this
control scheme, an object can be naturally specified with two drags: the
first is used to draw the major axes, the second to adjust the width.
Position is represented by [x y w h theta], where [x,y] give the top/left
corner of the rect PRIOR to rotation, [w,h] are the width and height, and
theta is the angle in degrees. The final rect is given by first placing
the rect at [x,y], then rotating it by theta around it's center. The
advantage of this is that if theta=0, the first four elements are
identical to the standard rect representation. The disadvantage is that
[x,y] need not lie in the interior of the rect after rotation.
USAGE
[h,api] = imRectRot( varargin )
INPUTS
varargin - parameters (struct or name/value pairs)
.hParent - [gca] object parent, typically an axes object
.ellipse - [0] if true display ellipse otherwise display rectangle
.rotate - [1] determines if object is axis aligned
.pos - [] initial pos vector [x y w h theta] or [] or [x y]
.lims - [] rectangle defining valid region for object placement
.showLims - [0] draw rectangle representing lims
.color - ['g'] color for the displayed object
.colorc - ['b'] color for the control point displaying orientation
.lw - [2] 'LineWidth' property for the displayed object
.ls - ['-'] 'LineStyle' property for the displayed object
.cross - [0] if 1 show diagonal, if 2 show cross
OUTPUTS
h - handle used to delete object
api - interface allowing access to created object
.getPos() - get position - returns 5 elt pos
.setPos(pos) - set position (while respecting constraints)
.setPosLock(b) - if lock set (b==true), object cannot change
.setSizLock(b) - if lock set (b==true), object cannot change size
.setDrgLock(b) - if lock set (b==true), object cannot be dragged
.setSidLock(lk) - [4x1] set locks for each side (tp/rt/bt/lf)
.setPosChnCb(f) - whenever pos changes (even slightly), calls f(pos)
.setPosSetCb(f) - whenever pos finished changing, calls f(pos)
.uistack(...) - calls 'uistack( [objectHandles], ... )', see uistack
.setStyle(...) - set line style (ls), width (lw), color and colorc
EXAMPLE - interactively place simple axis aligned rectangle
figure(1), imshow peppers.png;
[h,api]=imRectRot('rotate',0);
api.setPosChnCb( @(pos) disp(num2str(pos)) );
EXAMPLE - create rotatable ellpise that falls inside image
figure(1); I=imread('cameraman.tif'); imshow(I); siz=size(I);
[h,api]=imRectRot('pos',[60 60 40 40 45],'lims',[1 1 siz(1:2)-2 0],...
'showLims',1,'ellipse',1,'rotate',1,'color','w','colorc','y' );
api.setPosSetCb( @(pos) disp(num2str(pos)) );
See also IMRECT, RECTANGLE, PATCH
Piotr's Computer Vision Matlab Toolbox Version 2.51
Copyright 2014 Piotr Dollar. [pdollar-at-gmail.com]
Licensed under the Simplified BSD License [see external/bsd.txt]