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// This file was generated by gir (https://github.com/gtk-rs/gir)
// from gir-files (https://github.com/gtk-rs/gir-files.git)
// DO NOT EDIT

use crate::DrawContext;
#[cfg(any(feature = "v4_6", feature = "dox"))]
#[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
use crate::GLAPI;
#[cfg(any(feature = "v4_6", feature = "dox"))]
#[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
use glib::object::Cast;
use glib::object::IsA;
#[cfg(any(feature = "v4_6", feature = "dox"))]
#[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
use glib::signal::connect_raw;
#[cfg(any(feature = "v4_6", feature = "dox"))]
#[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
use glib::signal::SignalHandlerId;
use glib::translate::*;
#[cfg(any(feature = "v4_6", feature = "dox"))]
#[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
use std::boxed::Box as Box_;
use std::fmt;
use std::mem;
#[cfg(any(feature = "v4_6", feature = "dox"))]
#[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
use std::mem::transmute;
use std::ptr;

glib::wrapper! {
    /// [`GLContext`][crate::GLContext] is an object representing a platform-specific
    /// OpenGL draw context.
    ///
    /// [`GLContext`][crate::GLContext]s are created for a surface using
    /// [`SurfaceExt::create_gl_context()`][crate::prelude::SurfaceExt::create_gl_context()], and the context will match
    /// the characteristics of the surface.
    ///
    /// A [`GLContext`][crate::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 [`draw_from_gl()`][crate::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`][crate::GLContext] is platform-specific and context creation
    /// can fail, returning [`None`] context.
    ///
    /// A [`GLContext`][crate::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`][crate::GLContext] instance you need a [`Surface`][crate::Surface],
    /// which you typically get during the realize call of a widget.
    ///
    /// A [`GLContext`][crate::GLContext] is not realized until either [`GLContextExt::make_current()`][crate::prelude::GLContextExt::make_current()]
    /// or [`GLContextExt::realize()`][crate::prelude::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()`][crate::prelude::SurfaceExt::create_gl_context()] by calling [`GLContextExt::realize()`][crate::prelude::GLContextExt::realize()].
    /// If the realization fails you have the option to change the settings of
    /// the [`GLContext`][crate::GLContext] and try again.
    ///
    /// ## Using a GdkGLContext
    ///
    /// You will need to make the [`GLContext`][crate::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 ⚠️**
    ///
    /// ```c
    /// gdk_gl_context_make_current (context);
    /// ```
    ///
    /// You can now perform your drawing using OpenGL commands.
    ///
    /// You can check which [`GLContext`][crate::GLContext] is the current one by using
    /// [`current()`][Self::current()]; you can also unset any [`GLContext`][crate::GLContext]
    /// that is currently set by calling [`clear_current()`][Self::clear_current()].
    ///
    /// This is an Abstract Base Class, you cannot instantiate it.
    ///
    /// # Implements
    ///
    /// [`GLContextExt`][trait@crate::prelude::GLContextExt], [`DrawContextExt`][trait@crate::prelude::DrawContextExt], [`DrawContextExtManual`][trait@crate::prelude::DrawContextExtManual]
    #[doc(alias = "GdkGLContext")]
    pub struct GLContext(Object<ffi::GdkGLContext>) @extends DrawContext;

    match fn {
        type_ => || ffi::gdk_gl_context_get_type(),
    }
}

impl GLContext {
    pub const NONE: Option<&'static GLContext> = None;

    /// Clears the current [`GLContext`][crate::GLContext].
    ///
    /// Any OpenGL call after this function returns will be ignored
    /// until [`GLContextExt::make_current()`][crate::prelude::GLContextExt::make_current()] is called.
    #[doc(alias = "gdk_gl_context_clear_current")]
    pub fn clear_current() {
        assert_initialized_main_thread!();
        unsafe {
            ffi::gdk_gl_context_clear_current();
        }
    }

    /// Retrieves the current [`GLContext`][crate::GLContext].
    ///
    /// # Returns
    ///
    /// the current [`GLContext`][crate::GLContext]
    #[doc(alias = "gdk_gl_context_get_current")]
    #[doc(alias = "get_current")]
    pub fn current() -> Option<GLContext> {
        assert_initialized_main_thread!();
        unsafe { from_glib_none(ffi::gdk_gl_context_get_current()) }
    }
}

/// Trait containing all [`struct@GLContext`] methods.
///
/// # Implementors
///
/// [`GLContext`][struct@crate::GLContext]
pub trait GLContextExt: 'static {
    /// Gets the allowed APIs set via gdk_gl_context_set_allowed_apis().
    ///
    /// # Returns
    ///
    /// the allowed APIs
    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    #[doc(alias = "gdk_gl_context_get_allowed_apis")]
    #[doc(alias = "get_allowed_apis")]
    fn allowed_apis(&self) -> GLAPI;

    /// Gets the API currently in use.
    ///
    /// If the renderer has not been realized yet, 0 is returned.
    ///
    /// # Returns
    ///
    /// the currently used API
    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    #[doc(alias = "gdk_gl_context_get_api")]
    #[doc(alias = "get_api")]
    fn api(&self) -> GLAPI;

    /// Retrieves whether the context is doing extra validations and runtime checking.
    ///
    /// See [`set_debug_enabled()`][Self::set_debug_enabled()].
    ///
    /// # Returns
    ///
    /// [`true`] if debugging is enabled
    #[doc(alias = "gdk_gl_context_get_debug_enabled")]
    #[doc(alias = "get_debug_enabled")]
    fn is_debug_enabled(&self) -> bool;

    /// Retrieves whether the context is forward-compatible.
    ///
    /// See [`set_forward_compatible()`][Self::set_forward_compatible()].
    ///
    /// # Returns
    ///
    /// [`true`] if the context should be forward-compatible
    #[doc(alias = "gdk_gl_context_get_forward_compatible")]
    #[doc(alias = "get_forward_compatible")]
    fn is_forward_compatible(&self) -> bool;

    /// Retrieves required OpenGL version.
    ///
    /// See [`set_required_version()`][Self::set_required_version()].
    ///
    /// # Returns
    ///
    ///
    /// ## `major`
    /// return location for the major version to request
    ///
    /// ## `minor`
    /// return location for the minor version to request
    #[doc(alias = "gdk_gl_context_get_required_version")]
    #[doc(alias = "get_required_version")]
    fn required_version(&self) -> (i32, i32);

    /// Used to retrieves the [`GLContext`][crate::GLContext] that this @self share data with.
    ///
    /// As many contexts can share data now and no single shared context exists
    /// anymore, this function has been deprecated and now always returns [`None`].
    ///
    /// # Deprecated since 4.4
    ///
    /// Use [`is_shared()`][Self::is_shared()] to check if contexts
    ///   can be shared.
    ///
    /// # Returns
    ///
    /// [`None`]
    #[cfg_attr(feature = "v4_4", deprecated = "Since 4.4")]
    #[doc(alias = "gdk_gl_context_get_shared_context")]
    #[doc(alias = "get_shared_context")]
    #[must_use]
    fn shared_context(&self) -> Option<GLContext>;

    /// Checks whether the @self is using an OpenGL or OpenGL ES profile.
    ///
    /// # Returns
    ///
    /// [`true`] if the [`GLContext`][crate::GLContext] is using an OpenGL ES profile
    #[doc(alias = "gdk_gl_context_get_use_es")]
    #[doc(alias = "get_use_es")]
    fn uses_es(&self) -> bool;

    /// Retrieves the OpenGL version of the @self.
    ///
    /// The @self must be realized prior to calling this function.
    ///
    /// # Returns
    ///
    ///
    /// ## `major`
    /// return location for the major version
    ///
    /// ## `minor`
    /// return location for the minor version
    #[doc(alias = "gdk_gl_context_get_version")]
    #[doc(alias = "get_version")]
    fn version(&self) -> (i32, i32);

    /// Whether the [`GLContext`][crate::GLContext] is in legacy mode or not.
    ///
    /// The [`GLContext`][crate::GLContext] must be realized before calling this function.
    ///
    /// When realizing a GL context, GDK will try to use the OpenGL 3.2 core
    /// profile; this profile removes all the OpenGL API that was deprecated
    /// prior to the 3.2 version of the specification. If the realization is
    /// successful, this function will return [`false`].
    ///
    /// If the underlying OpenGL implementation does not support core profiles,
    /// GDK will fall back to a pre-3.2 compatibility profile, and this function
    /// will return [`true`].
    ///
    /// You can use the value returned by this function to decide which kind
    /// of OpenGL API to use, or whether to do extension discovery, or what
    /// kind of shader programs to load.
    ///
    /// # Returns
    ///
    /// [`true`] if the GL context is in legacy mode
    #[doc(alias = "gdk_gl_context_is_legacy")]
    fn is_legacy(&self) -> bool;

    /// Checks if the two GL contexts can share resources.
    ///
    /// When they can, the texture IDs from @other can be used in @self. This
    /// is particularly useful when passing [`GLTexture`][crate::GLTexture] objects between
    /// different contexts.
    ///
    /// Contexts created for the same display with the same properties will
    /// always be compatible, even if they are created for different surfaces.
    /// For other contexts it depends on the GL backend.
    ///
    /// Both contexts must be realized for this check to succeed. If either one
    /// is not, this function will return [`false`].
    /// ## `other`
    /// the [`GLContext`][crate::GLContext] that should be compatible with @self
    ///
    /// # Returns
    ///
    /// [`true`] if the two GL contexts are compatible.
    #[cfg(any(feature = "v4_4", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_4")))]
    #[doc(alias = "gdk_gl_context_is_shared")]
    fn is_shared(&self, other: &impl IsA<GLContext>) -> bool;

    /// Makes the @self the current one.
    #[doc(alias = "gdk_gl_context_make_current")]
    fn make_current(&self);

    /// Realizes the given [`GLContext`][crate::GLContext].
    ///
    /// It is safe to call this function on a realized [`GLContext`][crate::GLContext].
    ///
    /// # Returns
    ///
    /// [`true`] if the context is realized
    #[doc(alias = "gdk_gl_context_realize")]
    fn realize(&self) -> Result<(), glib::Error>;

    /// Sets the allowed APIs. When gdk_gl_context_realize() is called, only the
    /// allowed APIs will be tried. If you set this to 0, realizing will always fail.
    ///
    /// If you set it on a realized context, the property will not have any effect.
    /// It is only relevant during gdk_gl_context_realize().
    ///
    /// By default, all APIs are allowed.
    /// ## `apis`
    /// the allowed APIs
    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    #[doc(alias = "gdk_gl_context_set_allowed_apis")]
    fn set_allowed_apis(&self, apis: GLAPI);

    /// Sets whether the [`GLContext`][crate::GLContext] should perform extra validations and
    /// runtime checking.
    ///
    /// This is useful during development, but has additional overhead.
    ///
    /// The [`GLContext`][crate::GLContext] must not be realized or made current prior to
    /// calling this function.
    /// ## `enabled`
    /// whether to enable debugging in the context
    #[doc(alias = "gdk_gl_context_set_debug_enabled")]
    fn set_debug_enabled(&self, enabled: bool);

    /// Sets whether the [`GLContext`][crate::GLContext] should be forward-compatible.
    ///
    /// Forward-compatible contexts must not support OpenGL functionality that
    /// has been marked as deprecated in the requested version; non-forward
    /// compatible contexts, on the other hand, must support both deprecated and
    /// non deprecated functionality.
    ///
    /// The [`GLContext`][crate::GLContext] must not be realized or made current prior to calling
    /// this function.
    /// ## `compatible`
    /// whether the context should be forward-compatible
    #[doc(alias = "gdk_gl_context_set_forward_compatible")]
    fn set_forward_compatible(&self, compatible: bool);

    /// Sets the major and minor version of OpenGL to request.
    ///
    /// Setting @major and @minor to zero will use the default values.
    ///
    /// The [`GLContext`][crate::GLContext] must not be realized or made current prior to calling
    /// this function.
    /// ## `major`
    /// the major version to request
    /// ## `minor`
    /// the minor version to request
    #[doc(alias = "gdk_gl_context_set_required_version")]
    fn set_required_version(&self, major: i32, minor: i32);

    /// Requests that GDK create an OpenGL ES context instead of an OpenGL one.
    ///
    /// Not all platforms support OpenGL ES.
    ///
    /// The @self must not have been realized.
    ///
    /// By default, GDK will attempt to automatically detect whether the
    /// underlying GL implementation is OpenGL or OpenGL ES once the @self
    /// is realized.
    ///
    /// You should check the return value of [`uses_es()`][Self::uses_es()]
    /// after calling [`realize()`][Self::realize()] to decide whether to use
    /// the OpenGL or OpenGL ES API, extensions, or shaders.
    /// ## `use_es`
    /// whether the context should use OpenGL ES instead of OpenGL,
    ///   or -1 to allow auto-detection
    #[doc(alias = "gdk_gl_context_set_use_es")]
    fn set_use_es(&self, use_es: i32);

    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    #[doc(alias = "allowed-apis")]
    fn connect_allowed_apis_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;

    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    #[doc(alias = "api")]
    fn connect_api_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
}

impl<O: IsA<GLContext>> GLContextExt for O {
    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    fn allowed_apis(&self) -> GLAPI {
        unsafe {
            from_glib(ffi::gdk_gl_context_get_allowed_apis(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    fn api(&self) -> GLAPI {
        unsafe { from_glib(ffi::gdk_gl_context_get_api(self.as_ref().to_glib_none().0)) }
    }

    fn is_debug_enabled(&self) -> bool {
        unsafe {
            from_glib(ffi::gdk_gl_context_get_debug_enabled(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    fn is_forward_compatible(&self) -> bool {
        unsafe {
            from_glib(ffi::gdk_gl_context_get_forward_compatible(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    fn required_version(&self) -> (i32, i32) {
        unsafe {
            let mut major = mem::MaybeUninit::uninit();
            let mut minor = mem::MaybeUninit::uninit();
            ffi::gdk_gl_context_get_required_version(
                self.as_ref().to_glib_none().0,
                major.as_mut_ptr(),
                minor.as_mut_ptr(),
            );
            let major = major.assume_init();
            let minor = minor.assume_init();
            (major, minor)
        }
    }

    fn shared_context(&self) -> Option<GLContext> {
        unsafe {
            from_glib_none(ffi::gdk_gl_context_get_shared_context(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    fn uses_es(&self) -> bool {
        unsafe {
            from_glib(ffi::gdk_gl_context_get_use_es(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    fn version(&self) -> (i32, i32) {
        unsafe {
            let mut major = mem::MaybeUninit::uninit();
            let mut minor = mem::MaybeUninit::uninit();
            ffi::gdk_gl_context_get_version(
                self.as_ref().to_glib_none().0,
                major.as_mut_ptr(),
                minor.as_mut_ptr(),
            );
            let major = major.assume_init();
            let minor = minor.assume_init();
            (major, minor)
        }
    }

    fn is_legacy(&self) -> bool {
        unsafe {
            from_glib(ffi::gdk_gl_context_is_legacy(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    #[cfg(any(feature = "v4_4", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_4")))]
    fn is_shared(&self, other: &impl IsA<GLContext>) -> bool {
        unsafe {
            from_glib(ffi::gdk_gl_context_is_shared(
                self.as_ref().to_glib_none().0,
                other.as_ref().to_glib_none().0,
            ))
        }
    }

    fn make_current(&self) {
        unsafe {
            ffi::gdk_gl_context_make_current(self.as_ref().to_glib_none().0);
        }
    }

    fn realize(&self) -> Result<(), glib::Error> {
        unsafe {
            let mut error = ptr::null_mut();
            let is_ok = ffi::gdk_gl_context_realize(self.as_ref().to_glib_none().0, &mut error);
            assert_eq!(is_ok == glib::ffi::GFALSE, !error.is_null());
            if error.is_null() {
                Ok(())
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    fn set_allowed_apis(&self, apis: GLAPI) {
        unsafe {
            ffi::gdk_gl_context_set_allowed_apis(self.as_ref().to_glib_none().0, apis.into_glib());
        }
    }

    fn set_debug_enabled(&self, enabled: bool) {
        unsafe {
            ffi::gdk_gl_context_set_debug_enabled(
                self.as_ref().to_glib_none().0,
                enabled.into_glib(),
            );
        }
    }

    fn set_forward_compatible(&self, compatible: bool) {
        unsafe {
            ffi::gdk_gl_context_set_forward_compatible(
                self.as_ref().to_glib_none().0,
                compatible.into_glib(),
            );
        }
    }

    fn set_required_version(&self, major: i32, minor: i32) {
        unsafe {
            ffi::gdk_gl_context_set_required_version(self.as_ref().to_glib_none().0, major, minor);
        }
    }

    fn set_use_es(&self, use_es: i32) {
        unsafe {
            ffi::gdk_gl_context_set_use_es(self.as_ref().to_glib_none().0, use_es);
        }
    }

    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    fn connect_allowed_apis_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_allowed_apis_trampoline<
            P: IsA<GLContext>,
            F: Fn(&P) + 'static,
        >(
            this: *mut ffi::GdkGLContext,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLContext::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::allowed-apis\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_allowed_apis_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[cfg(any(feature = "v4_6", feature = "dox"))]
    #[cfg_attr(feature = "dox", doc(cfg(feature = "v4_6")))]
    fn connect_api_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_api_trampoline<P: IsA<GLContext>, F: Fn(&P) + 'static>(
            this: *mut ffi::GdkGLContext,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLContext::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::api\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_api_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }
}

impl fmt::Display for GLContext {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.write_str("GLContext")
    }
}