15.3.3.6 Image Properties

Properties of image objects (see image):

alphadata: scalar | matrix, def. 1

Transparency is not yet implemented for image objects. alphadata is unused.

alphadatamapping: "direct" | {"none"} | "scaled"

Transparency is not yet implemented for image objects. alphadatamapping is unused.

beingdeleted: {"off"} | "on"

busyaction: "cancel" | {"queue"}

Define how Octave handles the execution of this object’s callback properties when it is unable to interrupt another object’s executing callback. This is only relevant when the currently executing callback object has its interruptible property set to "off". The busyaction property of the interrupting callback object indicates whether the interrupting callback is queued ("queue" (default)) or discarded ("cancel"). See Callbacks section.

buttondownfcn: string | function handle, def. [](0x0)

For information on how to write graphics listener functions see Callbacks section.

cdata: matrix, def. 64-by-64 double

cdatamapping: {"direct"} | "scaled"

children (read-only): vector of graphics handles, def. [](0x1)

children is unused.

clipping: "off" | {"on"}

If clipping is "on", the image is clipped in its parent axes limits.

createfcn: string | function handle, def. [](0x0)

Callback function executed immediately after image has been created. Function is set by using default property on root object, e.g., set (groot, "defaultimagecreatefcn", 'disp ("image created!")').

For information on how to write graphics listener functions see Callbacks section.

deletefcn: string | function handle, def. [](0x0)

Callback function executed immediately before image is deleted.

For information on how to write graphics listener functions see Callbacks section.

handlevisibility: "callback" | "off" | {"on"}

If handlevisibility is "off", the image’s handle is not visible in its parent’s "children" property.

hittest: "off" | {"on"}

Specify whether image processes mouse events or passes them to ancestors of the object. When enabled, the object may respond to mouse clicks by evaluating the "buttondownfcn", showing the uicontextmenu, and eventually becoming the root "currentobject". This property is only relevant when the object can accept mouse clicks which is determined by the "pickableparts" property. See pickableparts property.

interruptible: "off" | {"on"}

Specify whether this object’s callback functions may be interrupted by other callbacks. By default interruptible is "on" and callbacks that make use of drawnow, figure, waitfor, getframe or pause functions are eventually interrupted. See Callbacks section.

parent: graphics handle

Handle of the parent graphics object.

pickableparts: "all" | "none" | {"visible"}

Specify whether image will accept mouse clicks. By default, pickableparts is "visible" and only visible parts of the image or its children may react to mouse clicks. When pickableparts is "all" both visible and invisible parts (or children) may react to mouse clicks. When pickableparts is "none" mouse clicks on the object are ignored and transmitted to any objects underneath this one. When an object is configured to accept mouse clicks the "hittest" property will determine how they are processed. See hittest property.

selected: {"off"} | "on"

selectionhighlight: "off" | {"on"}

tag: string, def. ""

A user-defined string to label the graphics object.

type (read-only): string

Class name of the graphics object. type is always "image"

uicontextmenu: graphics handle, def. [](0x0)

Graphics handle of the uicontextmenu object that is currently associated to this image object.

userdata: Any Octave data, def. [](0x0)

User-defined data to associate with the graphics object.

visible: "off" | {"on"}

If visible is "off", the image is not rendered on screen.

xdata: two-element vector, def. [1 64]

Two-element vector [xfirst xlast] specifying the x coordinates of the centers of the first and last columns of the image.

Setting xdata to the empty matrix ([]) will restore the default value of [1 columns(image)].

ydata: two-element vector, def. [1 64]

Two-element vector [yfirst ylast] specifying the y coordinates of the centers of the first and last rows of the image.

Setting ydata to the empty matrix ([]) will restore the default value of [1 rows(image)].