Implement wlr-screencopy v1 (#243)

* Implement wlr-screencopy

* Finish the implementation

Lots of changes, mainly to fix transform handling. Turns out, grim
expects transformed buffers and untransforms them by itself using info
from wl_output. This means that render helpers needed to learn how to
actually render transformed buffers.

Also, it meant that y_invert is no longer needed.

Next, moved the rendering to the Screencopy frame handler. Turns out,
copy() is more or less expected to return immediately, whereas
copy_with_damage() is expected to wait until the next VBlank. At least
that's the intent I parse reading the protocol.

Finally, brought the version from 3 down to 1, because
copy_with_damage() will need bigger changes. Grim still works, others
not really, mainly because they bind v3 unnecessarily, even if they
don't use the damage request.

---------

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

1 files changed, 14 insertions, 1 deletions

diff --git a/src/handlers/mod.rs b/src/handlers/mod.rs
index 8e92ea6e..39173471 100644
--- a/src/handlers/mod.rs
+++ b/src/handlers/mod.rs
@@ -54,12 +54,13 @@ use smithay::{
     delegate_text_input_manager, delegate_virtual_keyboard_manager,
 };
 
-use crate::delegate_foreign_toplevel;
 use crate::niri::{ClientState, State};
 use crate::protocols::foreign_toplevel::{
     self, ForeignToplevelHandler, ForeignToplevelManagerState,
 };
+use crate::protocols::screencopy::{Screencopy, ScreencopyHandler};
 use crate::utils::output_size;
+use crate::{delegate_foreign_toplevel, delegate_screencopy};
 
 impl SeatHandler for State {
     type KeyboardFocus = WlSurface;
@@ -380,6 +381,18 @@ impl ForeignToplevelHandler for State {
 }
 delegate_foreign_toplevel!(State);
 
+impl ScreencopyHandler for State {
+    fn frame(&mut self, screencopy: Screencopy) {
+        if let Err(err) = self
+            .niri
+            .render_for_screencopy(&mut self.backend, screencopy)
+        {
+            warn!("error rendering for screencopy: {err:?}");
+        }
+    }
+}
+delegate_screencopy!(State);
+
 impl DrmLeaseHandler for State {
     fn drm_lease_state(&mut self, node: DrmNode) -> &mut DrmLeaseState {
         &mut self