Struct gstreamer::Preset

pub struct Preset { /* private fields */ }

This interface offers methods to query and manipulate parameter preset sets. A preset is a bunch of property settings, together with meta data and a name. The name of a preset serves as key for subsequent method calls to manipulate single presets. All instances of one type will share the list of presets. The list is created on demand, if presets are not used, the list is not created.

The interface comes with a default implementation that serves most plugins. Wrapper plugins will override most methods to implement support for the native preset format of those wrapped plugins. One method that is useful to be overridden is PresetExt::property_names(). With that one can control which properties are saved and in which order. When implementing support for read-only presets, one should set the vmethods for PresetExt::save_preset() and PresetExt::delete_preset() to None. Applications can use PresetExt::is_editable() to check for that.

The default implementation supports presets located in a system directory, application specific directory and in the users home directory. When getting a list of presets individual presets are read and overlaid in 1) system, 2) application and 3) user order. Whenever an earlier entry is newer, the later entries will be updated. Since 1.8 you can also provide extra paths where to find presets through the GST_PRESET_PATH environment variable. Presets found in those paths will be considered as “app presets”.

Implements

PresetExt

GLib type: GObject with reference counted clone semantics.

Implementations

impl Preset

pub const NONE: Option<&'static Preset> = None

pub fn app_dir() -> Option<PathBuf>

Gets the directory for application specific presets if set by the application.

Returns

the directory or None, don’t free or modify the string

pub fn set_app_dir(app_dir: impl AsRef<Path>) -> Result<(), BoolError>

Sets an extra directory as an absolute path that should be considered when looking for presets. Any presets in the application dir will shadow the system presets.

app_dir

the application specific preset dir

Returns

true for success, false if the dir already has been set

Trait Implementations

impl Clone for Preset

fn clone(&self) -> Self

Makes a clone of this shared reference.

This increments the strong reference count of the object. Dropping the object will decrement it again.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Preset

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl HasParamSpec for Preset

type ParamSpec = ParamSpecObject

type SetValue = Preset

Preferred value to be used as setter for the associated ParamSpec.

type BuilderFn = fn(_: &str) -> ParamSpecObjectBuilder<'_, Preset>

fn param_spec_builder() -> Self::BuilderFn

impl Hash for Preset

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Hashes the memory address of this object.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: PresetImpl> IsImplementable<T> for Preset

fn interface_init(_iface: &mut Interface<Self>)

Override the virtual methods of this interface for the given subclass and do other interface initialization.

fn instance_init(_instance: &mut InitializingObject<T>)

Instance specific initialization.

impl Ord for Preset

fn cmp(&self, other: &Self) -> Ordering

Comparison for two GObjects.

Compares the memory addresses of the provided objects.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl<OT: ObjectType> PartialEq<OT> for Preset

fn eq(&self, other: &OT) -> bool

Equality for two GObjects.

Two GObjects are equal if their memory addresses are equal.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<OT: ObjectType> PartialOrd<OT> for Preset

fn partial_cmp(&self, other: &OT) -> Option<Ordering>

Partial comparison for two GObjects.

Compares the memory addresses of the provided objects.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for Preset

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for Preset

impl Send for Preset

impl Sync for Preset