Clutter Reference Manual: ClutterPathConstraint

## ClutterPathConstraint ClutterPathConstraint — A constraint that follows a path |

## Synopsis

                        ClutterPathConstraint;
    ClutterConstraint * clutter_path_constraint_new         (ClutterPath *path,
                                                             gfloat offset);
    void                clutter_path_constraint_set_path    (ClutterPathConstraint *constraint,
                                                             ClutterPath *path);
    ClutterPath *       clutter_path_constraint_get_path    (ClutterPathConstraint *constraint);
    void                clutter_path_constraint_set_offset  (ClutterPathConstraint *constraint,
                                                             gfloat offset);
    gfloat              clutter_path_constraint_get_offset  (ClutterPathConstraint *constraint);

## Object Hierarchy

      GObject
       +----GInitiallyUnowned
             +----ClutterActorMeta
                   +----ClutterConstraint
                         +----ClutterPathConstraint

## Properties

      "offset"                   gfloat                : Read / Write
      "path"                     ClutterPath*          : Read / Write

## Signals

      "node-reached"                                   : Run Last

## Description

ClutterPathConstraint is a simple constraint that modifies the allocation of the ClutterActor to which it has been applied using a ClutterPath.

By setting the "offset" property it is possible to control how far along the path the ClutterActor should be.

ClutterPathConstraint is available since Clutter 1.6.

## Details

### ClutterPathConstraint

    typedef struct _ClutterPathConstraint ClutterPathConstraint;

ClutterPathConstraint is an opaque structure whose members cannot be directly accessed

Since 1.6

### clutter_path_constraint_new ()

    ClutterConstraint * clutter_path_constraint_new         (ClutterPath *path,
                                                             gfloat offset);

Creates a new ClutterPathConstraint with the given `path` and `offset`

`path` : | a ClutterPath, or `NULL`. [allow-none]
`offset` : | the offset along the ClutterPath
Returns : | the newly created ClutterPathConstraint

Since 1.6

### clutter_path_constraint_set_path ()

    void                clutter_path_constraint_set_path    (ClutterPathConstraint *constraint,
                                                             ClutterPath *path);

Sets the `path` to be followed by the ClutterPathConstraint.

The `constraint` will take ownership of the ClutterPath passed to this function.

`constraint` : | a ClutterPathConstraint
`path` : | a ClutterPath. [allow-none]

Since 1.6

### clutter_path_constraint_get_path ()

    ClutterPath *       clutter_path_constraint_get_path    (ClutterPathConstraint *constraint);

Retrieves a pointer to the ClutterPath used by `constraint`.

`constraint` : | a ClutterPathConstraint
Returns : | the ClutterPath used by the ClutterPathConstraint, or `NULL`. The returned ClutterPath is owned by the constraint and it should not be unreferenced. [transfer none]

Since 1.6

### clutter_path_constraint_set_offset ()

    void                clutter_path_constraint_set_offset  (ClutterPathConstraint *constraint,
                                                             gfloat offset);

Sets the offset along the ClutterPath used by `constraint`.

`constraint` : | a ClutterPathConstraint
`offset` : | the offset along the path

Since 1.6

### clutter_path_constraint_get_offset ()

    gfloat              clutter_path_constraint_get_offset  (ClutterPathConstraint *constraint);

Retrieves the offset along the ClutterPath used by `constraint`.

`constraint` : | a ClutterPathConstraint
Returns : | the offset

Since 1.6

## Property Details

### The `"offset"` property

      "offset"                   gfloat                : Read / Write

The offset along the "path", between -1.0 and 2.0.

Allowed values: [-1,2]

Default value: 0

Since 1.6

### The `"path"` property

      "path"                     ClutterPath*          : Read / Write

The ClutterPath used to constrain the position of an actor.

Since 1.6

## Signal Details

### The `"node-reached"` signal

    void                user_function                      (ClutterPathConstraint *constraint,
                                                            ClutterActor          *actor,
                                                            guint                  index,
                                                            gpointer               user_data)       : Run Last

The ::node-reached signal is emitted each time a "offset" value results in the actor passing a ClutterPathNode

`constraint` : | the ClutterPathConstraint that emitted the signal
`actor` : | the ClutterActor using the `constraint`
`index` : | the index of the node that has been reached
`user_data` : | user data set when the signal handler was connected.

Since 1.6