#### 15.3.3.8 Surface Properties

The `surface` properties are:

`alphadata`: scalar | matrix, def. `1`

  Transparency is not yet implemented for surface objects. `alphadata` is unused.

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

  Transparency is not yet implemented for surface objects. `alphadatamapping` is unused.

`ambientstrength`: scalar, def. `0.30000`

  Strength of the ambient light. Value between 0.0 and 1.0

`backfacelighting`: `"lit"` | {`"reverselit"`} | `"unlit"`

  `"lit"`: The normals are used as is for lighting. `"reverselit"`: The normals are always oriented towards the point of view. `"unlit"`: Faces with normals pointing away from the point of view are unlit.

`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. 3-by-3 double
`cdatamapping`: `"direct"` | {`"scaled"`}
`cdatasource`: def. `""`
`children` (read-only): vector of graphics handles, def. `[](0x1)`

  `children` is unused.

`clipping`: `"off"` | {`"on"`}

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

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

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

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

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

  Callback function executed immediately before surface is deleted.

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

`diffusestrength`: scalar, def. `0.60000`

  Strength of the diffuse reflex. Value between 0.0 (no diffuse reflex) and 1.0 (full diffuse reflex).

`displayname`: def. `""`

  Text for the legend entry corresponding to this surface.

`edgealpha`: scalar, def. `1`

  Transparency is not yet implemented for surface objects. `edgealpha` is unused.

`edgecolor`: def. `[0 0 0]`
`edgelighting`: `"flat"` | `"gouraud"` | {`"none"`} | `"phong"`

  When set to a value other than `"none"`, the edges of the object are drawn with light and shadow effects. Supported values are `"none"` (no lighting effects), `"flat"` (facetted look) and `"gouraud"` (linear interpolation of the lighting effects between the vertices). `"phong"` is deprecated and has the same effect as `"gouraud"`.

`facealpha`: scalar | `"flat"` | `"interp"` | `"texturemap"`, def. `1`

  Transparency level of the faces of the surface object. Only double values are supported at present where a value of 0 means complete transparency and a value of 1 means solid faces without transparency. Setting the property to `"flat"`, `"interp"` or `"texturemap"` causes the faces to not being rendered. Additionally, the faces are not sorted from back to front which might lead to unexpected results when rendering layered transparent faces.

`facecolor`: {`"flat"`} | `"interp"` | `"none"` | `"texturemap"`
`facelighting`: {`"flat"`} | `"gouraud"` | `"none"` | `"phong"`

  When set to a value other than `"none"`, the faces of the object are drawn with light and shadow effects. Supported values are `"none"` (no lighting effects), `"flat"` (facetted look) and `"gouraud"` (linear interpolation of the lighting effects between the vertices). `"phong"` is deprecated and has the same effect as `"gouraud"`.

`facenormals`: def. `[](0x0)`

  Face normals are used for lighting the edges or faces if the `edgelighting` or `facelighting` properties are set to `"flat"`. Setting `facenormals` also forces the `facenormalsmode` property to be set to `"manual"`

`facenormalsmode`: {`"auto"`} | `"manual"`

  If this property is set to `"auto"`, `facenormals` are automatically calculated if the `edgelighting` or `facelighting` property are set to `"flat"` and at least one `light` object is present and visible in the same axes.

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

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

`hittest`: `"off"` | {`"on"`}

  Specify whether surface 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.

`linestyle`: {`"-"`} | `"--"` | `"-."` | `":"` | `"none"`

  See Line Styles.

`linewidth`: def. `0.50000`

  See line linewidth property.

`marker`: `"*"` | `"+"` | `"."` | `"<"` | `">"` | `"^"` | `"d"` | `"diamond"` | `"h"` | `"hexagram"` | {`"none"`} | `"o"` | `"p"` | `"pentagram"` | `"s"` | `"square"` | `"v"` | `"x"`

  See Marker Styles.

`markeredgecolor`: {`"auto"`} | `"flat"` | `"none"`

  See line markeredgecolor property.

`markerfacecolor`: `"auto"` | `"flat"` | {`"none"`}

  See line markerfacecolor property.

`markersize`: scalar, def. `6`

  See line markersize property.

`meshstyle`: {`"both"`} | `"column"` | `"row"`
`parent`: graphics handle

  Handle of the parent graphics object.

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

  Specify whether surface will accept mouse clicks. By default, `pickableparts` is `"visible"` and only visible parts of the surface 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"`}
`specularcolorreflectance`: scalar, def. `1`

  Reflectance for specular color. Value between 0.0 (color of underlying face) and 1.0 (color of light source).

`specularexponent`: scalar, def. `10`

  Exponent for the specular reflex. The lower the value, the more the reflex is spread out.

`specularstrength`: scalar, def. `0.90000`

  Strength of the specular reflex. Value between 0.0 (no specular reflex) and 1.0 (full specular reflex).

`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 `"surface"`

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

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

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

  User-defined data to associate with the graphics object.

`vertexnormals`: def. `[](0x0)`

  Vertex normals are used for lighting the edges or faces if the `edgelighting` or `facelighting` properties are set to `"gouraud"`. Setting `vertexnormals` also forces the `vertexnormalsmode` property to be set to `"manual"`

`vertexnormalsmode`: {`"auto"`} | `"manual"`

  If this property is set to `"auto"`, `vertexnormals` are automatically calculated if the `edgelighting` or `facelighting` property are set to `"gouraud"` and at least one `light` object is present and visible in the same axes.

`visible`: `"off"` | {`"on"`}

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

`xdata`: matrix, def. `[1 2 3]`
`xdatasource`: def. `""`
`ydata`: matrix, def. `[1; 2; 3]`
`ydatasource`: def. `""`
`zdata`: matrix, def. 3-by-3 double
`zdatasource`: def. `""`