// 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::Accessible;
use crate::AccessibleRole;
use crate::Align;
use crate::Buildable;
use crate::ConstraintTarget;
use crate::LayoutManager;
use crate::Overflow;
use crate::Widget;
use glib::object::Cast;
use glib::object::IsA;
use glib::signal::connect_raw;
use glib::signal::SignalHandlerId;
use glib::translate::*;
use glib::StaticType;
use glib::ToValue;
use std::boxed::Box as Box_;
use std::fmt;
use std::mem;
use std::mem::transmute;

glib::wrapper! {
    /// [`GLArea`][crate::GLArea] is a widget that allows drawing with OpenGL.
    ///
    /// ![An example GtkGLArea](glarea.png)
    ///
    /// [`GLArea`][crate::GLArea] sets up its own [`gdk::GLContext`][crate::gdk::GLContext], and creates a custom
    /// GL framebuffer that the widget will do GL rendering onto. It also ensures
    /// that this framebuffer is the default GL rendering target when rendering.
    ///
    /// In order to draw, you have to connect to the `signal::GLArea::render`
    /// signal, or subclass [`GLArea`][crate::GLArea] and override the GtkGLAreaClass.render
    /// virtual function.
    ///
    /// The [`GLArea`][crate::GLArea] widget ensures that the [`gdk::GLContext`][crate::gdk::GLContext] is associated with
    /// the widget's drawing area, and it is kept updated when the size and
    /// position of the drawing area changes.
    ///
    /// ## Drawing with GtkGLArea
    ///
    /// The simplest way to draw using OpenGL commands in a [`GLArea`][crate::GLArea] is to
    /// create a widget instance and connect to the `signal::GLArea::render` signal:
    ///
    /// The ``render()`` function will be called when the [`GLArea`][crate::GLArea] is ready
    /// for you to draw its content:
    ///
    /// **⚠️ The following code is in c ⚠️**
    ///
    /// ```c
    /// static gboolean
    /// render (GtkGLArea *area, GdkGLContext *context)
    /// {
    ///   // inside this function it's safe to use GL; the given
    ///   // GdkGLContext has been made current to the drawable
    ///   // surface used by the `GtkGLArea` and the viewport has
    ///   // already been set to be the size of the allocation
    ///
    ///   // we can start by clearing the buffer
    ///   glClearColor (0, 0, 0, 0);
    ///   glClear (GL_COLOR_BUFFER_BIT);
    ///
    ///   // draw your object
    ///   // draw_an_object ();
    ///
    ///   // we completed our drawing; the draw commands will be
    ///   // flushed at the end of the signal emission chain, and
    ///   // the buffers will be drawn on the window
    ///   return TRUE;
    /// }
    ///
    /// void setup_glarea (void)
    /// {
    ///   // create a GtkGLArea instance
    ///   GtkWidget *gl_area = gtk_gl_area_new ();
    ///
    ///   // connect to the "render" signal
    ///   g_signal_connect (gl_area, "render", G_CALLBACK (render), NULL);
    /// }
    /// ```
    ///
    /// If you need to initialize OpenGL state, e.g. buffer objects or
    /// shaders, you should use the `signal::Widget::realize` signal;
    /// you can use the `signal::Widget::unrealize` signal to clean up.
    /// Since the [`gdk::GLContext`][crate::gdk::GLContext] creation and initialization may fail, you
    /// will need to check for errors, using [``GLAreaExt::error()``][crate::prelude::`GLAreaExt::error()`].
    ///
    /// An example of how to safely initialize the GL state is:
    ///
    /// **⚠️ The following code is in c ⚠️**
    ///
    /// ```c
    /// static void
    /// on_realize (GtkGLarea *area)
    /// {
    ///   // We need to make the context current if we want to
    ///   // call GL API
    ///   gtk_gl_area_make_current (area);
    ///
    ///   // If there were errors during the initialization or
    ///   // when trying to make the context current, this
    ///   // function will return a GError for you to catch
    ///   if (gtk_gl_area_get_error (area) != NULL)
    ///     return;
    ///
    ///   // You can also use gtk_gl_area_set_error() in order
    ///   // to show eventual initialization errors on the
    ///   // GtkGLArea widget itself
    ///   GError *internal_error = NULL;
    ///   init_buffer_objects (&error);
    ///   if (error != NULL)
    ///     {
    ///       gtk_gl_area_set_error (area, error);
    ///       g_error_free (error);
    ///       return;
    ///     }
    ///
    ///   init_shaders (&error);
    ///   if (error != NULL)
    ///     {
    ///       gtk_gl_area_set_error (area, error);
    ///       g_error_free (error);
    ///       return;
    ///     }
    /// }
    /// ```
    ///
    /// If you need to change the options for creating the [`gdk::GLContext`][crate::gdk::GLContext]
    /// you should use the `signal::GLArea::create-context` signal.
    ///
    /// # Implements
    ///
    /// [`GLAreaExt`][trait@crate::prelude::GLAreaExt], [`WidgetExt`][trait@crate::prelude::WidgetExt], [`trait@glib::ObjectExt`], [`AccessibleExt`][trait@crate::prelude::AccessibleExt], [`BuildableExt`][trait@crate::prelude::BuildableExt], [`ConstraintTargetExt`][trait@crate::prelude::ConstraintTargetExt], [`WidgetExtManual`][trait@crate::prelude::WidgetExtManual], [`AccessibleExtManual`][trait@crate::prelude::AccessibleExtManual]
    #[doc(alias = "GtkGLArea")]
    pub struct GLArea(Object<ffi::GtkGLArea, ffi::GtkGLAreaClass>) @extends Widget, @implements Accessible, Buildable, ConstraintTarget;

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

impl GLArea {
    /// Creates a new [`GLArea`][crate::GLArea] widget.
    ///
    /// # Returns
    ///
    /// a new [`GLArea`][crate::GLArea]
    #[doc(alias = "gtk_gl_area_new")]
    pub fn new() -> GLArea {
        assert_initialized_main_thread!();
        unsafe { Widget::from_glib_none(ffi::gtk_gl_area_new()).unsafe_cast() }
    }

    // rustdoc-stripper-ignore-next
    /// Creates a new builder-pattern struct instance to construct [`GLArea`] objects.
    ///
    /// This method returns an instance of [`GLAreaBuilder`] which can be used to create [`GLArea`] objects.
    pub fn builder() -> GLAreaBuilder {
        GLAreaBuilder::default()
    }
}

impl Default for GLArea {
    fn default() -> Self {
        Self::new()
    }
}

#[derive(Clone, Default)]
// rustdoc-stripper-ignore-next
/// A [builder-pattern] type to construct [`GLArea`] objects.
///
/// [builder-pattern]: https://doc.rust-lang.org/1.0.0/style/ownership/builders.html
pub struct GLAreaBuilder {
    auto_render: Option<bool>,
    has_depth_buffer: Option<bool>,
    has_stencil_buffer: Option<bool>,
    use_es: Option<bool>,
    can_focus: Option<bool>,
    can_target: Option<bool>,
    css_classes: Option<Vec<String>>,
    css_name: Option<String>,
    cursor: Option<gdk::Cursor>,
    focus_on_click: Option<bool>,
    focusable: Option<bool>,
    halign: Option<Align>,
    has_tooltip: Option<bool>,
    height_request: Option<i32>,
    hexpand: Option<bool>,
    hexpand_set: Option<bool>,
    layout_manager: Option<LayoutManager>,
    margin_bottom: Option<i32>,
    margin_end: Option<i32>,
    margin_start: Option<i32>,
    margin_top: Option<i32>,
    name: Option<String>,
    opacity: Option<f64>,
    overflow: Option<Overflow>,
    receives_default: Option<bool>,
    sensitive: Option<bool>,
    tooltip_markup: Option<String>,
    tooltip_text: Option<String>,
    valign: Option<Align>,
    vexpand: Option<bool>,
    vexpand_set: Option<bool>,
    visible: Option<bool>,
    width_request: Option<i32>,
    accessible_role: Option<AccessibleRole>,
}

impl GLAreaBuilder {
    // rustdoc-stripper-ignore-next
    /// Create a new [`GLAreaBuilder`].
    pub fn new() -> Self {
        Self::default()
    }

    // rustdoc-stripper-ignore-next
    /// Build the [`GLArea`].
    pub fn build(self) -> GLArea {
        let mut properties: Vec<(&str, &dyn ToValue)> = vec![];
        if let Some(ref auto_render) = self.auto_render {
            properties.push(("auto-render", auto_render));
        }
        if let Some(ref has_depth_buffer) = self.has_depth_buffer {
            properties.push(("has-depth-buffer", has_depth_buffer));
        }
        if let Some(ref has_stencil_buffer) = self.has_stencil_buffer {
            properties.push(("has-stencil-buffer", has_stencil_buffer));
        }
        if let Some(ref use_es) = self.use_es {
            properties.push(("use-es", use_es));
        }
        if let Some(ref can_focus) = self.can_focus {
            properties.push(("can-focus", can_focus));
        }
        if let Some(ref can_target) = self.can_target {
            properties.push(("can-target", can_target));
        }
        if let Some(ref css_classes) = self.css_classes {
            properties.push(("css-classes", css_classes));
        }
        if let Some(ref css_name) = self.css_name {
            properties.push(("css-name", css_name));
        }
        if let Some(ref cursor) = self.cursor {
            properties.push(("cursor", cursor));
        }
        if let Some(ref focus_on_click) = self.focus_on_click {
            properties.push(("focus-on-click", focus_on_click));
        }
        if let Some(ref focusable) = self.focusable {
            properties.push(("focusable", focusable));
        }
        if let Some(ref halign) = self.halign {
            properties.push(("halign", halign));
        }
        if let Some(ref has_tooltip) = self.has_tooltip {
            properties.push(("has-tooltip", has_tooltip));
        }
        if let Some(ref height_request) = self.height_request {
            properties.push(("height-request", height_request));
        }
        if let Some(ref hexpand) = self.hexpand {
            properties.push(("hexpand", hexpand));
        }
        if let Some(ref hexpand_set) = self.hexpand_set {
            properties.push(("hexpand-set", hexpand_set));
        }
        if let Some(ref layout_manager) = self.layout_manager {
            properties.push(("layout-manager", layout_manager));
        }
        if let Some(ref margin_bottom) = self.margin_bottom {
            properties.push(("margin-bottom", margin_bottom));
        }
        if let Some(ref margin_end) = self.margin_end {
            properties.push(("margin-end", margin_end));
        }
        if let Some(ref margin_start) = self.margin_start {
            properties.push(("margin-start", margin_start));
        }
        if let Some(ref margin_top) = self.margin_top {
            properties.push(("margin-top", margin_top));
        }
        if let Some(ref name) = self.name {
            properties.push(("name", name));
        }
        if let Some(ref opacity) = self.opacity {
            properties.push(("opacity", opacity));
        }
        if let Some(ref overflow) = self.overflow {
            properties.push(("overflow", overflow));
        }
        if let Some(ref receives_default) = self.receives_default {
            properties.push(("receives-default", receives_default));
        }
        if let Some(ref sensitive) = self.sensitive {
            properties.push(("sensitive", sensitive));
        }
        if let Some(ref tooltip_markup) = self.tooltip_markup {
            properties.push(("tooltip-markup", tooltip_markup));
        }
        if let Some(ref tooltip_text) = self.tooltip_text {
            properties.push(("tooltip-text", tooltip_text));
        }
        if let Some(ref valign) = self.valign {
            properties.push(("valign", valign));
        }
        if let Some(ref vexpand) = self.vexpand {
            properties.push(("vexpand", vexpand));
        }
        if let Some(ref vexpand_set) = self.vexpand_set {
            properties.push(("vexpand-set", vexpand_set));
        }
        if let Some(ref visible) = self.visible {
            properties.push(("visible", visible));
        }
        if let Some(ref width_request) = self.width_request {
            properties.push(("width-request", width_request));
        }
        if let Some(ref accessible_role) = self.accessible_role {
            properties.push(("accessible-role", accessible_role));
        }
        glib::Object::new::<GLArea>(&properties).expect("Failed to create an instance of GLArea")
    }

    /// If set to [`true`] the ::render signal will be emitted every time
    /// the widget draws.
    ///
    /// This is the default and is useful if drawing the widget is faster.
    ///
    /// If set to [`false`] the data from previous rendering is kept around and will
    /// be used for drawing the widget the next time, unless the window is resized.
    /// In order to force a rendering [``GLAreaExt::queue_render()``][crate::prelude::`GLAreaExt::queue_render()`] must be called.
    /// This mode is useful when the scene changes seldom, but takes a long time
    /// to redraw.
    pub fn auto_render(mut self, auto_render: bool) -> Self {
        self.auto_render = Some(auto_render);
        self
    }

    /// If set to [`true`] the widget will allocate and enable a depth buffer for the
    /// target framebuffer.
    pub fn has_depth_buffer(mut self, has_depth_buffer: bool) -> Self {
        self.has_depth_buffer = Some(has_depth_buffer);
        self
    }

    /// If set to [`true`] the widget will allocate and enable a stencil buffer for the
    /// target framebuffer.
    pub fn has_stencil_buffer(mut self, has_stencil_buffer: bool) -> Self {
        self.has_stencil_buffer = Some(has_stencil_buffer);
        self
    }

    /// If set to [`true`] the widget will try to create a [`gdk::GLContext`][crate::gdk::GLContext] using
    /// OpenGL ES instead of OpenGL.
    pub fn use_es(mut self, use_es: bool) -> Self {
        self.use_es = Some(use_es);
        self
    }

    /// Whether the widget or any of its descendents can accept
    /// the input focus.
    ///
    /// This property is meant to be set by widget implementations,
    /// typically in their instance init function.
    pub fn can_focus(mut self, can_focus: bool) -> Self {
        self.can_focus = Some(can_focus);
        self
    }

    /// Whether the widget can receive pointer events.
    pub fn can_target(mut self, can_target: bool) -> Self {
        self.can_target = Some(can_target);
        self
    }

    /// A list of css classes applied to this widget.
    pub fn css_classes(mut self, css_classes: Vec<String>) -> Self {
        self.css_classes = Some(css_classes);
        self
    }

    /// The name of this widget in the CSS tree.
    ///
    /// This property is meant to be set by widget implementations,
    /// typically in their instance init function.
    pub fn css_name(mut self, css_name: &str) -> Self {
        self.css_name = Some(css_name.to_string());
        self
    }

    /// The cursor used by `widget`.
    pub fn cursor(mut self, cursor: &gdk::Cursor) -> Self {
        self.cursor = Some(cursor.clone());
        self
    }

    /// Whether the widget should grab focus when it is clicked with the mouse.
    ///
    /// This property is only relevant for widgets that can take focus.
    pub fn focus_on_click(mut self, focus_on_click: bool) -> Self {
        self.focus_on_click = Some(focus_on_click);
        self
    }

    /// Whether this widget itself will accept the input focus.
    pub fn focusable(mut self, focusable: bool) -> Self {
        self.focusable = Some(focusable);
        self
    }

    /// How to distribute horizontal space if widget gets extra space.
    pub fn halign(mut self, halign: Align) -> Self {
        self.halign = Some(halign);
        self
    }

    /// Enables or disables the emission of the ::query-tooltip signal on `widget`.
    ///
    /// A value of [`true`] indicates that `widget` can have a tooltip, in this case
    /// the widget will be queried using `signal::Widget::query-tooltip` to
    /// determine whether it will provide a tooltip or not.
    pub fn has_tooltip(mut self, has_tooltip: bool) -> Self {
        self.has_tooltip = Some(has_tooltip);
        self
    }

    /// Override for height request of the widget.
    ///
    /// If this is -1, the natural request will be used.
    pub fn height_request(mut self, height_request: i32) -> Self {
        self.height_request = Some(height_request);
        self
    }

    /// Whether to expand horizontally.
    pub fn hexpand(mut self, hexpand: bool) -> Self {
        self.hexpand = Some(hexpand);
        self
    }

    /// Whether to use the `hexpand` property.
    pub fn hexpand_set(mut self, hexpand_set: bool) -> Self {
        self.hexpand_set = Some(hexpand_set);
        self
    }

    /// The [`LayoutManager`][crate::LayoutManager] instance to use to compute the preferred size
    /// of the widget, and allocate its children.
    ///
    /// This property is meant to be set by widget implementations,
    /// typically in their instance init function.
    pub fn layout_manager<P: IsA<LayoutManager>>(mut self, layout_manager: &P) -> Self {
        self.layout_manager = Some(layout_manager.clone().upcast());
        self
    }

    /// Margin on bottom side of widget.
    ///
    /// This property adds margin outside of the widget's normal size
    /// request, the margin will be added in addition to the size from
    /// [``WidgetExt::set_size_request()``][crate::prelude::`WidgetExt::set_size_request()`] for example.
    pub fn margin_bottom(mut self, margin_bottom: i32) -> Self {
        self.margin_bottom = Some(margin_bottom);
        self
    }

    /// Margin on end of widget, horizontally.
    ///
    /// This property supports left-to-right and right-to-left text
    /// directions.
    ///
    /// This property adds margin outside of the widget's normal size
    /// request, the margin will be added in addition to the size from
    /// [``WidgetExt::set_size_request()``][crate::prelude::`WidgetExt::set_size_request()`] for example.
    pub fn margin_end(mut self, margin_end: i32) -> Self {
        self.margin_end = Some(margin_end);
        self
    }

    /// Margin on start of widget, horizontally.
    ///
    /// This property supports left-to-right and right-to-left text
    /// directions.
    ///
    /// This property adds margin outside of the widget's normal size
    /// request, the margin will be added in addition to the size from
    /// [``WidgetExt::set_size_request()``][crate::prelude::`WidgetExt::set_size_request()`] for example.
    pub fn margin_start(mut self, margin_start: i32) -> Self {
        self.margin_start = Some(margin_start);
        self
    }

    /// Margin on top side of widget.
    ///
    /// This property adds margin outside of the widget's normal size
    /// request, the margin will be added in addition to the size from
    /// [``WidgetExt::set_size_request()``][crate::prelude::`WidgetExt::set_size_request()`] for example.
    pub fn margin_top(mut self, margin_top: i32) -> Self {
        self.margin_top = Some(margin_top);
        self
    }

    /// The name of the widget.
    pub fn name(mut self, name: &str) -> Self {
        self.name = Some(name.to_string());
        self
    }

    /// The requested opacity of the widget.
    pub fn opacity(mut self, opacity: f64) -> Self {
        self.opacity = Some(opacity);
        self
    }

    /// How content outside the widget's content area is treated.
    ///
    /// This property is meant to be set by widget implementations,
    /// typically in their instance init function.
    pub fn overflow(mut self, overflow: Overflow) -> Self {
        self.overflow = Some(overflow);
        self
    }

    /// Whether the widget will receive the default action when it is focused.
    pub fn receives_default(mut self, receives_default: bool) -> Self {
        self.receives_default = Some(receives_default);
        self
    }

    /// Whether the widget responds to input.
    pub fn sensitive(mut self, sensitive: bool) -> Self {
        self.sensitive = Some(sensitive);
        self
    }

    /// Sets the text of tooltip to be the given string, which is marked up
    /// with Pango markup.
    ///
    /// Also see [``Tooltip::set_markup()``][crate::`Tooltip::set_markup()`].
    ///
    /// This is a convenience property which will take care of getting the
    /// tooltip shown if the given string is not [`None`]:
    /// `property::Widget::has-tooltip` will automatically be set to [`true`]
    /// and there will be taken care of `signal::Widget::query-tooltip` in
    /// the default signal handler.
    ///
    /// Note that if both `property::Widget::tooltip-text` and
    /// `property::Widget::tooltip-markup` are set, the last one wins.
    pub fn tooltip_markup(mut self, tooltip_markup: &str) -> Self {
        self.tooltip_markup = Some(tooltip_markup.to_string());
        self
    }

    /// Sets the text of tooltip to be the given string.
    ///
    /// Also see [``Tooltip::set_text()``][crate::`Tooltip::set_text()`].
    ///
    /// This is a convenience property which will take care of getting the
    /// tooltip shown if the given string is not [`None`]:
    /// `property::Widget::has-tooltip` will automatically be set to [`true`]
    /// and there will be taken care of `signal::Widget::query-tooltip` in
    /// the default signal handler.
    ///
    /// Note that if both `property::Widget::tooltip-text` and
    /// `property::Widget::tooltip-markup` are set, the last one wins.
    pub fn tooltip_text(mut self, tooltip_text: &str) -> Self {
        self.tooltip_text = Some(tooltip_text.to_string());
        self
    }

    /// How to distribute vertical space if widget gets extra space.
    pub fn valign(mut self, valign: Align) -> Self {
        self.valign = Some(valign);
        self
    }

    /// Whether to expand vertically.
    pub fn vexpand(mut self, vexpand: bool) -> Self {
        self.vexpand = Some(vexpand);
        self
    }

    /// Whether to use the `vexpand` property.
    pub fn vexpand_set(mut self, vexpand_set: bool) -> Self {
        self.vexpand_set = Some(vexpand_set);
        self
    }

    /// Whether the widget is visible.
    pub fn visible(mut self, visible: bool) -> Self {
        self.visible = Some(visible);
        self
    }

    /// Override for width request of the widget.
    ///
    /// If this is -1, the natural request will be used.
    pub fn width_request(mut self, width_request: i32) -> Self {
        self.width_request = Some(width_request);
        self
    }

    /// The accessible role of the given [`Accessible`][crate::Accessible] implementation.
    ///
    /// The accessible role cannot be changed once set.
    pub fn accessible_role(mut self, accessible_role: AccessibleRole) -> Self {
        self.accessible_role = Some(accessible_role);
        self
    }
}

pub const NONE_GL_AREA: Option<&GLArea> = None;

/// Trait containing all [`struct@GLArea`] methods.
///
/// # Implementors
///
/// [`GLArea`][struct@crate::GLArea]
pub trait GLAreaExt: 'static {
    /// Binds buffers to the framebuffer.
    ///
    /// Ensures that the `self` framebuffer object is made the current draw
    /// and read target, and that all the required buffers for the `self`
    /// are created and bound to the framebuffer.
    ///
    /// This function is automatically called before emitting the
    /// `signal::GLArea::render` signal, and doesn't normally need to be
    /// called by application code.
    #[doc(alias = "gtk_gl_area_attach_buffers")]
    fn attach_buffers(&self);

    /// Returns whether the area is in auto render mode or not.
    ///
    /// # Returns
    ///
    /// [`true`] if the `self` is auto rendering, [`false`] otherwise
    #[doc(alias = "gtk_gl_area_get_auto_render")]
    #[doc(alias = "get_auto_render")]
    fn is_auto_render(&self) -> bool;

    /// Retrieves the [`gdk::GLContext`][crate::gdk::GLContext] used by `self`.
    ///
    /// # Returns
    ///
    /// the [`gdk::GLContext`][crate::gdk::GLContext]
    #[doc(alias = "gtk_gl_area_get_context")]
    #[doc(alias = "get_context")]
    fn context(&self) -> Option<gdk::GLContext>;

    /// Gets the current error set on the `self`.
    ///
    /// # Returns
    ///
    /// the `GError`
    #[doc(alias = "gtk_gl_area_get_error")]
    #[doc(alias = "get_error")]
    fn error(&self) -> Option<glib::Error>;

    /// Returns whether the area has a depth buffer.
    ///
    /// # Returns
    ///
    /// [`true`] if the `self` has a depth buffer, [`false`] otherwise
    #[doc(alias = "gtk_gl_area_get_has_depth_buffer")]
    #[doc(alias = "get_has_depth_buffer")]
    fn has_depth_buffer(&self) -> bool;

    /// Returns whether the area has a stencil buffer.
    ///
    /// # Returns
    ///
    /// [`true`] if the `self` has a stencil buffer, [`false`] otherwise
    #[doc(alias = "gtk_gl_area_get_has_stencil_buffer")]
    #[doc(alias = "get_has_stencil_buffer")]
    fn has_stencil_buffer(&self) -> bool;

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

    /// Returns whether the [`GLArea`][crate::GLArea] should use OpenGL ES.
    ///
    /// See [``set_use_es()``][`Self::set_use_es()`].
    ///
    /// # Returns
    ///
    /// [`true`] if the [`GLArea`][crate::GLArea] should create an OpenGL ES context
    ///  and [`false`] otherwise
    #[doc(alias = "gtk_gl_area_get_use_es")]
    #[doc(alias = "get_use_es")]
    fn uses_es(&self) -> bool;

    /// Ensures that the [`gdk::GLContext`][crate::gdk::GLContext] used by `self` is associated with
    /// the [`GLArea`][crate::GLArea].
    ///
    /// This function is automatically called before emitting the
    /// `signal::GLArea::render` signal, and doesn't normally need
    /// to be called by application code.
    #[doc(alias = "gtk_gl_area_make_current")]
    fn make_current(&self);

    /// Marks the currently rendered data (if any) as invalid, and queues
    /// a redraw of the widget.
    ///
    /// This ensures that the `signal::GLArea::render` signal
    /// is emitted during the draw.
    ///
    /// This is only needed when [``set_auto_render()``][`Self::set_auto_render()`] has
    /// been called with a [`false`] value. The default behaviour is to
    /// emit `signal::GLArea::render` on each draw.
    #[doc(alias = "gtk_gl_area_queue_render")]
    fn queue_render(&self);

    /// Sets whether the [`GLArea`][crate::GLArea] is in auto render mode.
    ///
    /// If `auto_render` is [`true`] the `signal::GLArea::render` signal will
    /// be emitted every time the widget draws. This is the default and is
    /// useful if drawing the widget is faster.
    ///
    /// If `auto_render` is [`false`] the data from previous rendering is kept
    /// around and will be used for drawing the widget the next time,
    /// unless the window is resized. In order to force a rendering
    /// [``queue_render()``][`Self::queue_render()`] must be called. This mode is
    /// useful when the scene changes seldom, but takes a long time to redraw.
    /// ## `auto_render`
    /// a boolean
    #[doc(alias = "gtk_gl_area_set_auto_render")]
    fn set_auto_render(&self, auto_render: bool);

    /// Sets an error on the area which will be shown instead of the
    /// GL rendering.
    ///
    /// This is useful in the `signal::GLArea::create-context`
    /// signal if GL context creation fails.
    /// ## `error`
    /// a new `GError`, or [`None`] to unset the error
    #[doc(alias = "gtk_gl_area_set_error")]
    fn set_error(&self, error: Option<&glib::Error>);

    /// Sets whether the [`GLArea`][crate::GLArea] should use a depth buffer.
    ///
    /// If `has_depth_buffer` is [`true`] the widget will allocate and
    /// enable a depth buffer for the target framebuffer. Otherwise
    /// there will be none.
    /// ## `has_depth_buffer`
    /// [`true`] to add a depth buffer
    #[doc(alias = "gtk_gl_area_set_has_depth_buffer")]
    fn set_has_depth_buffer(&self, has_depth_buffer: bool);

    /// Sets whether the [`GLArea`][crate::GLArea] should use a stencil buffer.
    ///
    /// If `has_stencil_buffer` is [`true`] the widget will allocate and
    /// enable a stencil buffer for the target framebuffer. Otherwise
    /// there will be none.
    /// ## `has_stencil_buffer`
    /// [`true`] to add a stencil buffer
    #[doc(alias = "gtk_gl_area_set_has_stencil_buffer")]
    fn set_has_stencil_buffer(&self, has_stencil_buffer: bool);

    /// Sets the required version of OpenGL to be used when creating
    /// the context for the widget.
    ///
    /// This function must be called before the area has been realized.
    /// ## `major`
    /// the major version
    /// ## `minor`
    /// the minor version
    #[doc(alias = "gtk_gl_area_set_required_version")]
    fn set_required_version(&self, major: i32, minor: i32);

    /// Sets whether the `self` should create an OpenGL or an OpenGL ES context.
    ///
    /// You should check the capabilities of the [`gdk::GLContext`][crate::gdk::GLContext] before drawing
    /// with either API.
    /// ## `use_es`
    /// whether to use OpenGL or OpenGL ES
    #[doc(alias = "gtk_gl_area_set_use_es")]
    fn set_use_es(&self, use_es: bool);

    /// Emitted when the widget is being realized.
    ///
    /// This allows you to override how the GL context is created.
    /// This is useful when you want to reuse an existing GL context,
    /// or if you want to try creating different kinds of GL options.
    ///
    /// If context creation fails then the signal handler can use
    /// [``set_error()``][`Self::set_error()`] to register a more detailed error
    /// of how the construction failed.
    ///
    /// # Returns
    ///
    /// a newly created [`gdk::GLContext`][crate::gdk::GLContext];
    ///  the [`GLArea`][crate::GLArea] widget will take ownership of the returned value.
    #[doc(alias = "create-context")]
    fn connect_create_context<F: Fn(&Self) -> Option<gdk::GLContext> + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId;

    /// Emitted every time the contents of the [`GLArea`][crate::GLArea] should be redrawn.
    ///
    /// The `context` is bound to the `area` prior to emitting this function,
    /// and the buffers are painted to the window once the emission terminates.
    /// ## `context`
    /// the [`gdk::GLContext`][crate::gdk::GLContext] used by `area`
    ///
    /// # Returns
    ///
    /// [`true`] to stop other handlers from being invoked for the event.
    ///  [`false`] to propagate the event further.
    #[doc(alias = "render")]
    fn connect_render<F: Fn(&Self, &gdk::GLContext) -> glib::signal::Inhibit + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId;

    /// Emitted once when the widget is realized, and then each time the widget
    /// is changed while realized.
    ///
    /// This is useful in order to keep GL state up to date with the widget size,
    /// like for instance camera properties which may depend on the width/height
    /// ratio.
    ///
    /// The GL context for the area is guaranteed to be current when this signal
    /// is emitted.
    ///
    /// The default handler sets up the GL viewport.
    /// ## `width`
    /// the width of the viewport
    /// ## `height`
    /// the height of the viewport
    #[doc(alias = "resize")]
    fn connect_resize<F: Fn(&Self, i32, i32) + 'static>(&self, f: F) -> SignalHandlerId;

    #[doc(alias = "auto-render")]
    fn connect_auto_render_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;

    #[doc(alias = "context")]
    fn connect_context_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;

    #[doc(alias = "has-depth-buffer")]
    fn connect_has_depth_buffer_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;

    #[doc(alias = "has-stencil-buffer")]
    fn connect_has_stencil_buffer_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;

    #[doc(alias = "use-es")]
    fn connect_use_es_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
}

impl<O: IsA<GLArea>> GLAreaExt for O {
    fn attach_buffers(&self) {
        unsafe {
            ffi::gtk_gl_area_attach_buffers(self.as_ref().to_glib_none().0);
        }
    }

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

    fn context(&self) -> Option<gdk::GLContext> {
        unsafe { from_glib_none(ffi::gtk_gl_area_get_context(self.as_ref().to_glib_none().0)) }
    }

    fn error(&self) -> Option<glib::Error> {
        unsafe { from_glib_none(ffi::gtk_gl_area_get_error(self.as_ref().to_glib_none().0)) }
    }

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

    fn has_stencil_buffer(&self) -> bool {
        unsafe {
            from_glib(ffi::gtk_gl_area_get_has_stencil_buffer(
                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::gtk_gl_area_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 uses_es(&self) -> bool {
        unsafe { from_glib(ffi::gtk_gl_area_get_use_es(self.as_ref().to_glib_none().0)) }
    }

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

    fn queue_render(&self) {
        unsafe {
            ffi::gtk_gl_area_queue_render(self.as_ref().to_glib_none().0);
        }
    }

    fn set_auto_render(&self, auto_render: bool) {
        unsafe {
            ffi::gtk_gl_area_set_auto_render(
                self.as_ref().to_glib_none().0,
                auto_render.into_glib(),
            );
        }
    }

    fn set_error(&self, error: Option<&glib::Error>) {
        unsafe {
            ffi::gtk_gl_area_set_error(self.as_ref().to_glib_none().0, error.to_glib_none().0);
        }
    }

    fn set_has_depth_buffer(&self, has_depth_buffer: bool) {
        unsafe {
            ffi::gtk_gl_area_set_has_depth_buffer(
                self.as_ref().to_glib_none().0,
                has_depth_buffer.into_glib(),
            );
        }
    }

    fn set_has_stencil_buffer(&self, has_stencil_buffer: bool) {
        unsafe {
            ffi::gtk_gl_area_set_has_stencil_buffer(
                self.as_ref().to_glib_none().0,
                has_stencil_buffer.into_glib(),
            );
        }
    }

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

    fn set_use_es(&self, use_es: bool) {
        unsafe {
            ffi::gtk_gl_area_set_use_es(self.as_ref().to_glib_none().0, use_es.into_glib());
        }
    }

    fn connect_create_context<F: Fn(&Self) -> Option<gdk::GLContext> + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn create_context_trampoline<
            P: IsA<GLArea>,
            F: Fn(&P) -> Option<gdk::GLContext> + 'static,
        >(
            this: *mut ffi::GtkGLArea,
            f: glib::ffi::gpointer,
        ) -> *mut gdk::ffi::GdkGLContext {
            let f: &F = &*(f as *const F);
            f(GLArea::from_glib_borrow(this).unsafe_cast_ref()).to_glib_full()
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"create-context\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    create_context_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_render<F: Fn(&Self, &gdk::GLContext) -> glib::signal::Inhibit + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn render_trampoline<
            P: IsA<GLArea>,
            F: Fn(&P, &gdk::GLContext) -> glib::signal::Inhibit + 'static,
        >(
            this: *mut ffi::GtkGLArea,
            context: *mut gdk::ffi::GdkGLContext,
            f: glib::ffi::gpointer,
        ) -> glib::ffi::gboolean {
            let f: &F = &*(f as *const F);
            f(
                GLArea::from_glib_borrow(this).unsafe_cast_ref(),
                &from_glib_borrow(context),
            )
            .into_glib()
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"render\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    render_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_resize<F: Fn(&Self, i32, i32) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn resize_trampoline<P: IsA<GLArea>, F: Fn(&P, i32, i32) + 'static>(
            this: *mut ffi::GtkGLArea,
            width: libc::c_int,
            height: libc::c_int,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(
                GLArea::from_glib_borrow(this).unsafe_cast_ref(),
                width,
                height,
            )
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"resize\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    resize_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_auto_render_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_auto_render_trampoline<P: IsA<GLArea>, F: Fn(&P) + 'static>(
            this: *mut ffi::GtkGLArea,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLArea::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::auto-render\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_auto_render_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_context_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_context_trampoline<P: IsA<GLArea>, F: Fn(&P) + 'static>(
            this: *mut ffi::GtkGLArea,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLArea::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::context\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_context_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_has_depth_buffer_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_has_depth_buffer_trampoline<
            P: IsA<GLArea>,
            F: Fn(&P) + 'static,
        >(
            this: *mut ffi::GtkGLArea,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLArea::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::has-depth-buffer\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_has_depth_buffer_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_has_stencil_buffer_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_has_stencil_buffer_trampoline<
            P: IsA<GLArea>,
            F: Fn(&P) + 'static,
        >(
            this: *mut ffi::GtkGLArea,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLArea::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::has-stencil-buffer\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_has_stencil_buffer_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    fn connect_use_es_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_use_es_trampoline<P: IsA<GLArea>, F: Fn(&P) + 'static>(
            this: *mut ffi::GtkGLArea,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(GLArea::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::use-es\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_use_es_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }
}

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