smithay/anvil/src/buffer_utils.rs

63 lines
1.9 KiB
Rust

use std::{cell::RefCell, rc::Rc};
use slog::Logger;
#[cfg(feature = "egl")]
use smithay::backend::egl::display::EGLBufferReader;
use smithay::{
reexports::wayland_server::protocol::wl_buffer::WlBuffer,
wayland::shm::with_buffer_contents as shm_buffer_contents,
};
/// Utilities for working with `WlBuffer`s.
#[derive(Clone)]
pub struct BufferUtils {
#[cfg(feature = "egl")]
egl_buffer_reader: Rc<RefCell<Option<EGLBufferReader>>>,
log: Logger,
}
impl BufferUtils {
/// Creates a new `BufferUtils`.
#[cfg(feature = "egl")]
pub fn new(egl_buffer_reader: Rc<RefCell<Option<EGLBufferReader>>>, log: Logger) -> Self {
Self {
egl_buffer_reader,
log,
}
}
/// Creates a new `BufferUtils`.
#[cfg(not(feature = "egl"))]
pub fn new(log: Logger) -> Self {
Self { log }
}
/// Returns the dimensions of an image stored in the buffer.
#[cfg(feature = "egl")]
pub fn dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
// Try to retrieve the EGL dimensions of this buffer, and, if that fails, the shm dimensions.
self.egl_buffer_reader
.borrow()
.as_ref()
.and_then(|display| display.egl_buffer_dimensions(buffer))
.or_else(|| self.shm_buffer_dimensions(buffer))
}
/// Returns the dimensions of an image stored in the buffer.
#[cfg(not(feature = "egl"))]
pub fn dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
self.shm_buffer_dimensions(buffer)
}
/// Returns the dimensions of an image stored in the shm buffer.
fn shm_buffer_dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
shm_buffer_contents(buffer, |_, data| (data.width, data.height))
.map_err(|err| {
warn!(self.log, "Unable to load buffer contents"; "err" => format!("{:?}", err));
err
})
.ok()
}
}