Cuboid

Cuboidal region of interest

Description

The Cuboid object is a cuboidal region-of-interest (ROI).

To draw the ROI, position the cursor on the ROI and click and drag to move or change the size of the shape. To finish the ROI, release the mouse button. For more information about using this ROI, including keyboard shortcuts and a right-click context menu, see Tips.

Creation

Description

To create a Cuboid ROI, use the images.roi.cuboid creation function. After creating the object, call the draw object function to begin drawing. As a convenience, you can also use the drawcuboid function to create a Cuboid ROI. The drawcuboid function creates the ROI object and automatically calls the draw object function.

roi = images.roi.Cuboid creates a Cuboid ROI object with default properties.

roi = images.roi.Cuboid(ax) creates a Cuboid ROI object on the axes specified by ax.

roi = images.roi.Cuboid(___,Name,Value)sets properties using name-value pairs. For example, images.roi.Cuboid('Color','y') sets the color of the Cuboid object to yellow. You can specify multiple name-value pairs. Enclose each property name in single quotes.

Input Arguments

ax — Parent of ROI

gca (default) | Axes object | UIAxes object

Parent of the ROI, specified as an Axes object or UIAxes object. For information about using an ROI in a UIAxes, including important limitations, see Using ROIs in Apps Created with App Designer.

Properties

Color — ROI color

blue (default) | ColorSpec

ROI color, specified as a MATLAB^® ColorSpec (Color Specification).

Example: 'green'

Example: 'g'

Example: [0 1 0]

Deletable — ROI can be interactively deleted via context menu

true (default) | false

ROI can be interactively deleted via a context menu, specified as true or false. When the value is true (default), you can delete the ROI via the context menu. To disable this context menu item, set this property to false. When the value is set to false, you can still delete the ROI by calling the delete function specifying the handle to the ROI as the input.

DrawingArea — Area of axes in which you can interactively place ROI

'auto' (default) | 'unlimited' | 1-by-6 numeric array

Area of the axes in which you can interactively place the ROI, specified as one of the values in this table.

Value	Description
'auto'	The drawing area is a superset of the current axes limits and a bounding box that surrounds the ROI (default).
'unlimited'	The drawing area has no boundary and ROIs can be drawn or dragged to extend beyond the axes limits.
[x,y,z,w,h,d]	The drawing area is restricted to a region beginning at (x,y,z), with width w, height h, and depth d.

EdgeAlpha — Transparency of ROI edge

1 (default) | nonnegative numeric scalar

Transparency of ROI edge, specified as a nonnegative numeric scalar value in the range [0 1]. When set to 1, the ROI edge is fully opaque. When set to 0, the ROI edge is completely transparent.

Example: drawcuboid('EdgeAlpha',0.2)

FaceAlpha — Transparency of ROI faces

0.2 (default) | numeric scalar

Transparency of the ROI faces, specified as a numeric scalar value in the range [0 1]. When the value is 1, the ROI faces are fully opaque. When the value is 0, the ROI faces are completely transparent.

FaceAlphaOnHover — Transparency of ROI face directly underneath mouse pointer

0.4 (default) | nonnegative numeric scalar | 'none'

Transparency of ROI face directly underneath the mouse pointer, specified as a scalar value in the range [0 1] or 'none', to indicate no change to face transparency. When set to 1, the face under the mouse pointer is fully opaque. When set to 0, the face is completely transparent.

Example: drawcuboid('FaceAlphaOnHover',1)

FaceColorOnHover — Color of ROI face directly underneath mouse pointer

'none' (default) | MATLABColorSpec

Color of the ROI face directly underneath the mouse pointer, specified as a MATLAB ColorSpec (Color Specification) or 'none'. By default, the face color does not change on hover. When you are not hovering over a face of the ROI, the value of the ROI Color property determines the face color. The intensities must be in the range [0,1].

Example: drawcuboid('FaceAlphaOnHover',1)

HandleVisibility — Visibility of ROI handle in Children property of parent

'on' (default) | 'off' | 'callback'

Visibility of the ROI handle in the Children property of the parent, specified as one of the values in this table.

Value	Description
'on'	The object handle is always visible (default).
'off'	The object handle is hidden at all times.
'callback'	The object handle is visible from within callbacks or functions invoked by callbacks, but not from within functions invoked from the command line.

InteractionsAllowed — Interactivity of ROI

'all' (default) | 'none' | 'translate'

Interactivity of the ROI, specified as one of the values in this table.

Value	Description
'all'	The ROI is fully interactable (default).
'none'	The ROI is not interactable, and no drag points are visible.
'translate'	The ROI can be translated (moved) within the drawing area.

Label — ROI label

'' (default) | character vector | string

ROI label, specified as a character vector or string. By default, the ROI has no label ('').

LabelVisible — Visibility of the label

'on' (default) | 'off' | 'hover'

Visibility of the label, specified as one of these values:

Value	Description
'on'	Label is visible when the ROI is visible and the Label property is nonempty (default).
'hover'	Label is visible only when the mouse is hovering over the ROI.
'off'	Label is not visible.

LineWidth — Width of ROI edge

1 (default) | positive numeric scalar

Width of the ROI edge, specified as a positive numeric scalar in points.

Parent — ROI parent

Axes object | UIAxes object

ROI parent, specified as an Axes or UIAxes object. For information about using an ROI in a UIAxes, including important limitations, see Using ROIs in Apps Created with App Designer.

Position — Position of the cuboid

1-by-6 numeric array

Position of the cuboid, specified as a 1-by-6 array of the form [xmin, ymin, zmin, width, height, depth]. This property updates automatically when you draw or move the cuboid.

Rotatable — Ability of cuboid to be rotated

'none' (default) | 'x' | 'y' | 'z' | 'all'

Ability of the cuboid to be rotated, specified as one of these values:

Value	Description
'all'	ROI is fully rotatable.
'x'	ROI can only be rotated about the x axis
'y'	ROI can only be rotated about the y axis.
'z'	ROI can only be rotated about the z axis.
'none'	ROI is not rotatable.

RotationAngle — Angle of ROI rotation

[0 0 0] (default) | 1-by-3 numeric array of rotation angles

Angle of ROI rotation, specified as a 1-by-3 numeric array of rotation angles, measured in degrees. The rotation angles array is of the form [x_angle y_angle z_angle], measured about the x-, y-, and z-axis, respectively. Rotation is applied about the ROI centroid in order z, then y, then x.

The value of RotationAngle does not impact the values in the Position property. Position represents the cuboid prior to any rotation. When you rotate the cuboid, use the Vertices property to determine the location of the rotated cuboid.

ScrollWheelDuringDraw — Ability of scroll wheel to adjust size

'all' (default) | xresize | yresize | zresize | 'none'

Ability of the scroll wheel to adjust the size of the cuboid during interactive placement, specified as one of these values:

Value	Description
'allresize'	Scroll wheel impacts all ROI dimensions.
'xresize'	Scroll wheel impacts only the x dimension.
'yresize'	Scroll wheel impacts only the y dimension.
'zresize'	Scroll wheel impacts only the z dimension.
'none'	Scroll wheel has no effect.

Selected — Selection state of ROI

false (default) | true

Selection state of the ROI, specified as the logical value true or false. You can also set this property interactively. For example, clicking on the ROI selects the ROI and sets this property to true. Similarly, pressing the Ctrl key and clicking the ROI deselects the ROI and sets the value of this property to false.

SelectedColor — Color of ROI when selected

'none' (default) | ColorSpec

Color of the ROI when selected, specified as a MATLAB ColorSpec (Color Specification). The intensities must be in the range [0,1]. If 'SelectedColor' is set to 'none', then the value of Color defines the color of the ROI for all states, selected or not.

Example: 'green'

Example: 'g'

Example: [0 1 0]

StripeColor — Color of ROI stripe

'none' (default) | ColorSpec value

Color of the ROI stripe, specified as a MATLAB ColorSpec (Color Specification) value. By default, the edge of an ROI is solid colored. If you specify StripeColor, the ROI edge is striped. The striping consists of a combination of the value specified by 'Color' and this value.

Example: 'green'

Example: 'g'

Example: [0 1 0]

Tag — Tag to associate with the ROI

'' (default) | character vector | string scalar

Tag to associate with the ROI, specified as a character vector or string. Use the tag value to find the ROI object in a hierarchy of objects using the findobj function.

UIContextMenu — Context menu

ContextMenu object

Context menu, specified as a ContextMenu object. Use this property to display a custom context menu when you right-click the ROI. You can create a custom context menu by using the uicontextmenu function and then configuring context menu properties.

UserData — Data to associate with ROI

any MATLAB data

Data to associate with the ROI, specified as any MATLAB data. For example, you can specify a scalar, vector, matrix, cell array, string, character array, table, or structure. MATLAB does not use this data.

Vertices — Locations of corners of cuboidal ROI

8-by-3 numeric array

Locations of the corners of cuboidal ROI, returned as an 8-by-3 array.

Visible — ROI visibility

'on' (default) | 'off'

ROI visibility, specified as one of the values in this table.

Value	Description
'on'	Display the ROI (default).
'off'	Hide the ROI without deleting it. You still can access the properties of an invisible ROI.

Object Functions

addlistener	Create event listener bound to event source
beginDrawingFromPoint	Begin drawing ROI from specified point
bringToFront	Bring ROI to front of Axes stacking order
draw	Begin drawing ROI interactively
inROI	Query if points are located in ROI
wait	Block MATLAB command line until ROI operation is finished

Examples

Create Cuboid ROI on Scatter Plot

Define vectors for 3-D scatter data.

[x,y,z] = sphere(16);
X = [x(:)*.5 x(:)*.75 x(:)];
Y = [y(:)*.5 y(:)*.75 y(:)];
Z = [z(:)*.5 z(:)*.75 z(:)];

Specify the size and color of each marker.

S = repmat([1 .75 .5]*10,numel(x),1);
C = repmat([1 2 3],numel(x),1);

Create a 3-D scatter plot and use view to the change the angle of the axes in the figure.

figure
hScatter = scatter3(X(:),Y(:),Z(:),S(:),C(:),'filled'); 
view(-60,60);

Begin placing a cuboid in the axes that snaps to the nearest point from the scatter plot. Adjust the size of the cuboid during interactive placement by using the scroll wheel.

ax = gca;
h = images.roi.Cuboid(ax);
draw(h)

Set Up Listeners for Cuboid ROI Events

Define vectors for 3-D scattered data.

[x,y,z] = sphere(16);
X = [x(:)*.5 x(:)*.75 x(:)];
Y = [y(:)*.5 y(:)*.75 y(:)];
Z = [z(:)*.5 z(:)*.75 z(:)];

Specify the size and color of each marker.

S = repmat([1 .75 .5]*10,numel(x),1);
C = repmat([1 2 3],numel(x),1);

Create a 3-D scatter plot and use view to change the angle of the axes in the figure.

figure
hScatter = scatter3(X(:),Y(:),Z(:),S(:),C(:),'filled'); 
view(-60,60);

Create a Cuboid ROI object, specifying the color. Call the draw object function to enable interactive drawing of the cuboid shape.

roi = images.roi.Cuboid(gca,'Color','r');
draw(roi)

Set up listeners for ROI moving events. When you move it, the ROI sends notifications of these events and executes the callback function you specify.

addlistener(roi,'MovingROI',@allevents);
addlistener(roi,'ROIMoved',@allevents);

The allevents callback function displays the previous position and the current position of the ROI.

function allevents(src,evt)
    evname = evt.EventName;
    switch(evname)
        case{'MovingROI'}
            disp(['ROI moving previous position: ' mat2str(evt.PreviousPosition)]);
            disp(['ROI moving current position: ' mat2str(evt.CurrentPosition)]);
        case{'ROIMoved'}
            disp(['ROI moved previous position: ' mat2str(evt.PreviousPosition)]);
            disp(['ROI moved current position: ' mat2str(evt.CurrentPosition)]);
    end
end

More About

Events

To receive notification from the ROI when certain events happen, set up listeners for these events. You can specify a callback function that executes when one of these events occurs. When the ROI notifies your application through the listener, it returns data specific to the event. Look at the event class for the specific event to see what is returned.

For an example, see Set Up Listeners for Cuboid ROI Events.

Event Name	Trigger	Event Data	Event Attributes
DeletingROI	ROI is about to be interactively deleted.	event.EventData	NotifyAccess: private ListenAccess: public
DrawingStarted	ROI is about to be interactively drawn.	event.EventData	NotifyAccess: private ListenAccess: public
DrawingFinished	ROI has been interactively drawn.	event.EventData	NotifyAccess: private ListenAccess: public
MovingROI	ROI shape or location is being interactively changed.	images.roi.CuboidMovingEventData	NotifyAccess: private ListenAccess: public
ROIMoved	ROI shape or location has been interactively changed.	images.roi.CuboidMovingEventData	NotifyAccess: private ListenAccess: public
ROIClicked	ROI has been clicked.	images.roi.ROIClickedEventData	NotifyAccess: private ListenAccess: public

Tips

• The ROI supports the following interactivity, including keyboard shortcuts.

  Behavior	Keyboard shortcut
  Cancel drawing the ROI.	Press Esc. The function returns a valid ROI object with an empty Position field.
  Fine-tune width of ellipse as you are drawing.	As you draw the ellipse, use the scroll wheel to make small changes to the width of the ellipse.
  Rotate the ROI.	Position the pointer near a vertex. The pointer changes to the rotate pointer. Click and rotate the ROI on its center. To make the rotation snap at 15 degree angles, press Shift as you rotate.
  Maintain aspect ratio while drawing.	Hold the Shift key as you draw. Creates a circular ROI. To lock the aspect ratio, position the pointer on the ROI, right-click, and select Fix Aspect Ratio from the context menu
  Resize (reshape) the ROI.	Position pointer over a vertex and then click and drag. To main the aspect ratio as you resize, hold the Shift key.
  Move the ROI.	Position the pointer over the ROI. The pointer changes to the fleur shape. Click and drag to move the ROI.
  Delete the ROI.	Position the pointer over the ROI, right-click, and select Delete Cuboid from the context menu. You can also delete the ROI programmatically using the delete object function.

• For information about using an ROI in an app created with App Designer, see Using ROIs in Apps Created with App Designer.