Struct RenderContext 

pub struct RenderContext {
    pub display: Display,
    pub context: Context,
    pub surfaces: Vec<WindowSurface>,
    pub active_index: Option<usize>,
    pub gl_ver: String,
    pub glsl_ver: String,
    pub device: String,
    /* private fields */
}

EGL + OpenGL 4.6 context with support for multiple window surfaces.

Initialisation

Create a headless context for off-screen rendering:

let ctx = RenderContext::new_headless()?;

Or create a windowed context from a raw window handle:

let ctx = RenderContext::new_windowed(raw_handle, display_handle, size)?;

Multi-window

Additional windows can be attached with attach_window and made current with make_current.

Fields

display: Display

context: Context

surfaces: Vec<WindowSurface>

active_index: Option<usize>

gl_ver: String

glsl_ver: String

device: String

Implementations

impl RenderContext

pub fn new_headless() -> OpticResult<Self>

Creates a headless EGL context with a 1×1 pbuffer surface.

This is useful for off-screen rendering or when no window is available. Loads OpenGL function pointers via EGL and queries driver info.

pub fn new_windowed( raw_handle: RawWindowHandle, display_handle: RawDisplayHandle, size: Size2D, ) -> OpticResult<Self>

Creates a windowed EGL context from raw window and display handles.

Supports X11 (with optional visual ID matching), Wayland, and Win32 platforms. Falls back to the default EGL display if platform-specific display creation fails.

pub fn attach_window( &mut self, raw_handle: RawWindowHandle, size: Size2D, ) -> OpticResult<usize>

Attaches a new window surface to this context.

Returns the index of the new surface, which can be used with make_current.

pub fn resize_window(&mut self, index: usize, size: Size2D)

Resizes the tracked size for a window surface.

Does not call EGL surface resize — just updates the stored dimensions used by make_current for the viewport call.

pub fn make_current(&self, index: usize) -> OpticResult<()>

Makes the given surface current and sets the viewport.

pub fn swap_buffers(&self, index: usize) -> OpticResult<()>

Swaps front and back buffers for the given surface (double-buffering).

pub fn clear(&self)

Clears the colour and depth buffers of the currently bound framebuffer.

pub fn set_vsync(&self, enable: bool)

Enables or disables vertical sync (swap interval).

pub fn set_clear_color(&self, color: RGBA)

Sets the clear colour used by clear.

Trait Implementations

impl Drop for RenderContext

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.