Struct gdk4::GLContext [−][src]
pub struct GLContext(_);Expand description
GLContext is an object representing a platform-specific
OpenGL draw context.
GLContexts are created for a surface using
SurfaceExt::create_gl_context(), and the context will match
the the characteristics of the surface.
A GLContext is not tied to any particular normal framebuffer.
For instance, it cannot draw to the surface back buffer. The GDK
repaint system is in full control of the painting to that. Instead,
you can create render buffers or textures and use cairo_draw_from_gl()
in the draw function of your widget to draw them. Then GDK will handle
the integration of your rendering with that of other widgets.
Support for GLContext is platform-specific and context creation
can fail, returning None context.
A GLContext has to be made “current” in order to start using
it, otherwise any OpenGL call will be ignored.
Creating a new OpenGL context
In order to create a new GLContext instance you need a Surface,
which you typically get during the realize call of a widget.
A GLContext is not realized until either GLContextExt::make_current()
or GLContextExt::realize() is called. It is possible to specify
details of the GL context like the OpenGL version to be used, or whether
the GL context should have extra state validation enabled after calling
SurfaceExt::create_gl_context() by calling GLContextExt::realize().
If the realization fails you have the option to change the settings of
the GLContext and try again.
Using a GdkGLContext
You will need to make the GLContext the current context before issuing
OpenGL calls; the system sends OpenGL commands to whichever context is current.
It is possible to have multiple contexts, so you always need to ensure that
the one which you want to draw with is the current one before issuing commands:
⚠️ The following code is in c ⚠️
gdk_gl_context_make_current (context);You can now perform your drawing using OpenGL commands.
You can check which GLContext is the current one by using
current(); you can also unset any GLContext
that is currently set by calling clear_current().
This is an Abstract Base Class, you cannot instantiate it.
Implements
Implementations
Trait Implementations
type Parent = DrawContext
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <=
operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
Returns the type identifier of Self.
Auto Trait Implementations
impl RefUnwindSafe for GLContext
impl UnwindSafe for GLContext
Blanket Implementations
Mutably borrows from an owned value. Read more
Upcasts an object to a superclass or interface T. Read more
Upcasts an object to a reference of its superclass or interface T. Read more
Tries to downcast to a subclass or interface implementor T. Read more
Tries to downcast to a reference of its subclass or interface implementor T. Read more
Tries to cast to an object of type T. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast and upcast will do many checks at compile-time already. Read more
Tries to cast to reference to an object of type T. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast and upcast will do many checks at compile-time already. Read more
Casts to T unconditionally. Read more
Casts to &T unconditionally. Read more
Returns true if the object is an instance of (can be cast to) T.
pub fn set_property<'a, N, V>(
&self,
property_name: N,
value: V
) -> Result<(), BoolError> where
N: Into<&'a str>,
V: ToValue,
pub fn set_property_from_value<'a, N>(
&self,
property_name: N,
value: &Value
) -> Result<(), BoolError> where
N: Into<&'a str>,
pub fn set_properties_from_value(
&self,
property_values: &[(&str, Value)]
) -> Result<(), BoolError>
pub fn has_property<'a, N>(&self, property_name: N, type_: Option<Type>) -> bool where
N: Into<&'a str>,
pub fn find_property<'a, N>(&self, property_name: N) -> Option<ParamSpec> where
N: Into<&'a str>,
Safety Read more
Safety Read more
Safety Read more
Safety Read more
pub fn connect<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
N: Into<&'a str>,
F: 'static + Fn(&[Value]) -> Option<Value> + Send + Sync,
Same as connect but takes a SignalId instead of a signal name.
pub fn connect_local<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
N: Into<&'a str>,
F: 'static + Fn(&[Value]) -> Option<Value>,
Same as connect_local but takes a SignalId instead of a signal name.
pub unsafe fn connect_unsafe<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
N: Into<&'a str>,
F: Fn(&[Value]) -> Option<Value>,
Same as connect_unsafe but takes a SignalId instead of a signal name.
Emit signal by signal id.
Same as emit but takes Value for the arguments.
Emit signal by its name.
Same as emit_by_name but takes Value for the arguments.
Emit signal with details by signal id.
Same as emit_with_details but takes Value for the arguments.
pub fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec) + Send + Sync,
pub fn connect_notify_local<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec),
pub unsafe fn connect_notify_unsafe<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: Fn(&T, &ParamSpec),
pub fn bind_property<'a, O, N, M>(
&'a self,
source_property: N,
target: &'a O,
target_property: M
) -> BindingBuilder<'a> where
O: ObjectType,
N: Into<&'a str>,
M: Into<&'a str>,
Returns a SendValue clone of self.