Struct ScreenshotReadbacks 

pub(crate) struct ScreenshotReadbacks {
    pub(crate) slots: Vec<(Arc<ReadbackSlot>, Instant)>,
    pub(crate) storage: Option<Option<unsafe extern "system" fn(u32, isize, *const c_void, u32)>>,
}

The persistently mapped pixel-pack buffers GLES screenshots are read back into, so the compositor only issues the transfer and the caller copies the pixels out once the GPU has written them. Without GL_EXT_buffer_storage, or with PIXELFLUX_SCREENSHOT_SYNC set, the compositor reads back synchronously into the caller’s buffer instead. Declared ahead of the renderer in AppState, so its drop forgets every mapping, waiting out a copy under way, before the GL context goes away.

Fields

slots: Vec<(Arc<ReadbackSlot>, Instant)>

storage: Option<Option<unsafe extern "system" fn(u32, isize, *const c_void, u32)>>

The entry point, once looked up: None before the first GLES screenshot.

Implementations

impl ScreenshotReadbacks

pub(crate) fn lookup( gl: &Gles2, ) -> Option<unsafe extern "system" fn(u32, isize, *const c_void, u32)>

pub(crate) fn acquire( &mut self, gl: &Gles2, len: usize, now: Instant, ) -> Option<Arc<ReadbackSlot>>

A free slot of len bytes, made when none is; None sends the screenshot down the synchronous readback.

pub(crate) fn create( gl: &Gles2, storage: unsafe extern "system" fn(u32, isize, *const c_void, u32), len: usize, ) -> Option<ReadbackSlot>

pub(crate) fn delete(gl: &Gles2, slot: &ReadbackSlot)

pub(crate) fn has_idle(&self, now: Instant) -> bool

Whether a free slot has gone unused long enough to be deleted.

pub(crate) fn reap_idle(&mut self, gl: &Gles2, now: Instant)

Trait Implementations

impl Default for ScreenshotReadbacks

fn default() -> ScreenshotReadbacks

Returns the “default value” for a type.

impl Drop for ScreenshotReadbacks

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.